Lets see your Nixie Tube equipment - Page 1
Forum section: electronics / general

author: SLJ
author_rank: Frequent Contributor
timestamp: October 06, 2015, 01:14:58 pm
content: Since I collect antique test equipment I love Nixie Tube gear. Always interested in seeing what Nixies were used in. Here are a couple of mine.Everyone needs a calculator on the workbench - Remington Nixie Tube Calculator:HP Frequency Counter/DVM:OK, I showed you a couple of mine now show me yours...

author: SteveLy
author_rank: Regular Contributor
timestamp: October 06, 2015, 01:52:57 pm
content: Phew, only a 12 digit display. Nobody likes a show-off! ;-PI'm not showing mine because it's going to Dave's mailbag and I don't want to spoil it. It has something to do with electronics in Australia in the early 1970s.

author: dexters_lab
author_rank: Unknown
timestamp: October 09, 2015, 07:26:55 pm
content: Yea i have a soft spot for nixies... so fresh into the lab... a Solartron LM1619 volt meter and the nixies are not the only tubes in itoh and 1KV on unshrouded banana sockets? i guess things was different back then!

author: SLJ
author_rank: Frequent Contributor
timestamp: October 09, 2015, 10:47:33 pm
content: Quote from: dexters_lab on October 09, 2015, 07:26:55 pmNice... and love those banana plugs with the protruding set screws. Makes things more challenging.

author: dexters_lab
author_rank: Unknown
timestamp: October 10, 2015, 08:17:46 am
content: Quote from: SLJ on October 09, 2015, 10:47:33 pmlol, to be fair the banana plugs are just the output of one of my low voltage power supplies, we're all safe!

author: Arhammon
author_rank: Contributor
timestamp: October 11, 2015, 11:23:18 am
content: 1986 Soviet 7-digit DMM ?31 (31):

author: Vgkid
author_rank: Super Contributor
timestamp: October 12, 2015, 12:08:29 am
content: ^^^That looks cool. Can you post more pictures/ specs if you can find them.

author: Arhammon
author_rank: Contributor
timestamp: October 12, 2015, 09:12:22 am
content: I have some old photo:Oven: Main Zener, Divider 100V, 1000V.Analog unitManganin foil resistor network on boardAccuracy class, needed external standard cellAnd it is produced in 1987

author: RJFreeman
author_rank: Regular Contributor
timestamp: October 12, 2015, 11:10:45 am
content: HP521 - spot the dead Pentode and steamy electrolytic....

author: RJFreeman
author_rank: Regular Contributor
timestamp: October 12, 2015, 11:11:58 am
content: a few more

author: smbaker
author_rank: Regular Contributor
timestamp: October 12, 2015, 07:30:17 pm
content: Does it count if you built it yourself?

author: tautech
author_rank: Super Contributor
timestamp: October 12, 2015, 07:43:49 pm
content: This thread should be linked here:https://www.eevblog.com/forum/repair/nixie-tube-fluke-8100b-dmm/

author: RJFreeman
author_rank: Regular Contributor
timestamp: October 13, 2015, 12:17:08 am
content: Quote from: smbaker on October 12, 2015, 07:30:17 pmIt counts more if you built it yourself, and more again if you designed and built it yourself....

author: bitseeker
author_rank: Super Contributor
timestamp: October 13, 2015, 02:22:30 am
content: Thanks for starting this thread. Looking forward to seeing many more cool Nixies!

author: joeqsmith
author_rank: Super Contributor
timestamp: October 14, 2015, 02:25:38 am
content: Quote from: smbaker on October 12, 2015, 07:30:17 pmVery nice job. Do you have any details on the design?

author: lowimpedance
author_rank: Super Contributor
timestamp: October 15, 2015, 01:54:49 am
content: Quote from: smbaker on October 12, 2015, 07:30:17 pmEven more so.Quote from: RJFreeman on October 12, 2015, 11:10:45 amNever seen or heard of this beastie, interesting look. I like the number of tubes they managed to stuff in there.And now for a few of my 'orange displayed' kit. ;The 7205 works except for an fixed offset in the reading and no manual to tell me what the hell are all the trim pots with odd names mean.The 7004 works , but occasionally drifts off with a mind of its own !. Unable to track that issue down.The 6052 works fine.

author: lowimpedance
author_rank: Super Contributor
timestamp: October 15, 2015, 02:02:05 am
content: And two more ;The DT-360 works well and I have two of these with manuals.The Systron donor seems to work but has an issue with the decimal point and the case is missing !!

author: smbaker
author_rank: Regular Contributor
timestamp: October 15, 2015, 05:54:57 am
content: Quote from: joeqsmith on October 14, 2015, 02:25:38 amSure, on my blog athttp://www.smbaker.com/nixie-tube-calculator-powered-by-a-raspberry-piI tried this on Kickstarter last year, but unfortunately my price point was just too high for most people. I've made a few revisions since the photos were taken, for example the case is now fully enclosed. The thing is still sitting on my desk, it doubles as a clock.

author: joeqsmith
author_rank: Super Contributor
timestamp: October 15, 2015, 07:20:45 am
content: Quote from: smbaker on October 15, 2015, 05:54:57 amThank you for the link. I will read this when I have a chance.

author: vk6zgo
author_rank: Super Contributor
timestamp: October 15, 2015, 09:02:48 am
content: Before Test Equipment used nixies,there was this:-http://www.vintage-radio.net/forum/attachment.php?attachmentid=95035&d=1405098535

author: VK5RC
author_rank: Unknown
timestamp: October 15, 2015, 10:37:04 am
content: An old favourite and a newer one.

author: RJFreeman
author_rank: Regular Contributor
timestamp: October 15, 2015, 12:09:55 pm
content: Quote from: lowimpedance on October 15, 2015, 02:02:05 amAh, yes, You just reminded me I have a DT360, waiting repair somewhere....

author: lowimpedance
author_rank: Super Contributor
timestamp: October 15, 2015, 11:00:49 pm
content: Quote from: RJFreeman on October 15, 2015, 12:09:55 pmIn case you need the schemattics for the DT360, here you go;

author: Cubdriver
author_rank: Unknown
timestamp: October 21, 2015, 02:17:18 am
content: Here are two, with more to come as I resurrect them.HP 5245L counter:HP 3440A DVM:They have so much more personality than LCDs, and are just cool to look at.-Pat

author: TerraHertz
author_rank: Super Contributor
timestamp: October 24, 2015, 11:35:51 am
content: I only have a couple of nixie instruments, despite my avatar. One is a Systron Donner counter 1017, with 1291A 50-500MHz frequency converter. Doesn't work and so far I found a manual for the 1017, but nothing for the 1291A converter. I don't suppose anyone has a copy? I'd like to get this working. Mmmm... ring counters.Yes, it needs a clean. But I don't see much point, unless I can get it working.This is what my '5' avatar is taken from.The other is a HP 5326B Timer-counter-dvm. Works, could do with a clean and cal. Ahem... actually, all my multimeters could. There seems to be some disagreement...

author: snik
author_rank: Contributor
timestamp: October 28, 2015, 02:43:03 am
content: Here is my Nixie Tube equipment. An Heathkit IM-1202 Multimeter and two Frequency counter : Monsanto 100B & Philips PM 6607

author: RJFreeman
author_rank: Regular Contributor
timestamp: October 28, 2015, 05:36:52 am
content: Quote from: lowimpedance on October 15, 2015, 01:54:49 amit certainly is an interesting beasty - the modules at the top are removable and (apparently) generic counter modules model AC-4 decade counters. the HP521D (the one I have) uses the AC-4K which takes up to 120 Khz.The valves are twin triodes with each one making up a flip-flop (or 'Binary") so the 4 flip-flops make up the counter - although it doesn't quite put out regular BCD (not sure what this counter is called).the counter modules have a stair case output to let you make recordings on a chart recorder and decode to one of ten for the Nixie Tubes is done by an array of Neon lamps and photo resistors.For those who are interested, the manual for the AC-4 counters can be found here:http://www.nixiebunny.com/hpac4/index.html

author: edpalmer42
author_rank: Super Contributor
timestamp: October 29, 2015, 08:22:52 pm
content: My only piece of Nixie equipment is a Fluke 8375A DMM. 5.5 digit, one year accuracy of .01%, input impedance up to 10 Gohm, gold-plated traces on critical boards. I was surprised to see a flexible circuit board in a Nixie-equipped unit. I didn't realize that flexible circuits were used that far back. Date codes suggest that some boards have been swapped. They vary from '72 to '84.Ed

author: tautech
author_rank: Super Contributor
timestamp: October 29, 2015, 08:38:14 pm
content: Quote from: edpalmer42 on October 29, 2015, 08:22:52 pmYou shouldn't really be, flexi boards were common in auto dashboards even in the 70's.

author: LaurenceW
author_rank: Frequent Contributor
timestamp: October 30, 2015, 10:47:06 pm
content: Well there was this fella. It's big. And it tells the time. So I called it The BigTime.Radio synch, IR remote, chimes, ambient temperature and relay output. And it was BIG.

author: LaurenceW
author_rank: Frequent Contributor
timestamp: October 30, 2015, 10:50:07 pm
content: Oh, and this one. I was going to call it "one sixth of a BigTime", but it ended up with the slightly snappier "CYCLOX" miker, instead. Serial Man-Machine Interface!

author: bitseeker
author_rank: Super Contributor
timestamp: October 31, 2015, 01:45:55 am
content: Those are very cool, Lawrence. What do the neon bulbs on the far left and right of BigTime indicate?

author: LaurenceW
author_rank: Frequent Contributor
timestamp: November 01, 2015, 11:43:13 pm
content: Far left Neon is for AM/PM indicator (over here in Europe we prefer 24 hours a day rather than two lots of 12 (!), so it's superfluous)Far right neon indicates alarm is on/off or in snooze.Middle two neons just mark the seconds, really, but for added cool are PWM'd to fade dim/bright/dim...

author: bitseeker
author_rank: Super Contributor
timestamp: November 02, 2015, 06:04:33 pm
content: Breathing neon. Cool!On my own stuff, I use 24-hour time and yyyy-mm-dd date formats. They make more sense. The rest of the house, though, is US standard.

author: dr.diesel
author_rank: Super Contributor
timestamp: November 05, 2015, 01:17:48 pm
content: Here is one that's been sitting on the shelf for a couple years patiently awaiting a restoration.Systron Donner Model 6152 counter from 1971.

author: dr.diesel
author_rank: Super Contributor
timestamp: November 05, 2015, 06:00:19 pm
content: BK Model 281, currently employed as a DC battery bank monitor. Sorry for the crappy exposure, pretty dark in here, it's reading 13.3v.

author: Martin.M
author_rank: Frequent Contributor
timestamp: November 18, 2015, 04:44:35 pm
content: very nice equipments here. Where are the custom nixies?Grundig Counter UZ144 , the custom nixie can display ms, s, Hz and kHz. This unit is an OEM, made by Rohde&SchwarzHartman & Braun DC Voltmeter T2001 with VFD Tubes from Tung Sol they are well shieldet behind a metal meshgreetingsMartin

author: Cubdriver
author_rank: Unknown
timestamp: November 18, 2015, 09:26:47 pm
content: Very nice, Martin!-Pat

author: bitseeker
author_rank: Super Contributor
timestamp: November 19, 2015, 04:38:37 am
content: Martin, I really like the units tube on the Grundig Counter. Very cool.

author: med6753
author_rank: Super Contributor
timestamp: November 19, 2015, 01:37:54 pm
content: Bell and Howell (Heathkit) DVM. The '1' digit is actually a neon bulb.

author: krivx
author_rank: Frequent Contributor
timestamp: November 19, 2015, 02:11:08 pm
content: Quote from: dr.diesel on November 05, 2015, 01:17:48 pmDo you have a manual? I've had one for a while that also needs going over...

author: dr.diesel
author_rank: Super Contributor
timestamp: November 19, 2015, 02:12:21 pm
content: Quote from: krivx on November 19, 2015, 02:11:08 pmNope, no manuals, appears they are not readily available either.

author: krivx
author_rank: Frequent Contributor
timestamp: November 19, 2015, 02:19:47 pm
content: Quote from: dr.diesel on November 19, 2015, 02:12:21 pmYeah, just unanswered requests online. Shame...

author: Martin.M
author_rank: Frequent Contributor
timestamp: November 19, 2015, 04:15:52 pm
content: we can do the same, I will start restoring this 6053

author: fossi
author_rank: Contributor
timestamp: November 28, 2015, 11:09:08 am
content: some of my stuff.A frequency-counter from HEBanda flexibel instrument Symetra D from METRAWATT with plugin E12 for temperature measuring with different types of heat probes. There exists another plugin which works as multimeter.Interesting is the additional analog instrument underneath the nixies.

author: Cubdriver
author_rank: Unknown
timestamp: December 29, 2015, 09:24:32 am
content: A recent acquisition - a little 3-1/2 digit nixie meter. It's a United Systems Corp. 262A, made in early 1971 based on the date codes on the parts inside it. The case is a bit rough (it seems to be covered by something that feels slightly rubberized, and it's not fared well over the 45 years since it was made - it's rather scuffed and battered). It needs a good cleaning, but seems to work based on a quick checkout.It's mostly discrete construction, with a few 14 pin DIPS - some Motorola ones that appear to be simple logic chips based on what I've been able to find (don't have Motorola data books of that vintage), and some that might be Fairchild, that based on their number and location seem to have something to do with driving the nixies.A cool piece of equipment for $10.-Pat

author: SeanB
author_rank: Super Contributor
timestamp: December 29, 2015, 09:46:38 am
content: Looks like all the transistors are Motorola there, that shape and the dimple on top are very common on parts from them. The drivers are Fairchild.

author: cncjerry
author_rank: Unknown
timestamp: January 07, 2016, 04:04:40 pm
content: Not wild about the picture, but the meter works. I love old Keithley equipment.I've not had a lot of luck posting pictures, let's see if it works this time.

author: VK5RC
author_rank: Unknown
timestamp: January 09, 2016, 12:35:18 am
content: New 'toy' (Chistmas Present)

author: matseng
author_rank: Frequent Contributor
timestamp: January 09, 2016, 05:31:01 am
content: I really can't classify this as "equipment" even if it actually works as intended being a 0.1..999.9mA constant current load, but I thought that I'd just post it here anyways.I did this as my entry into the Dangerous Prototypes 7400-competition some years ago. It's a digitally controlled constant current load built out of 4000-series CMOS logic running at 12 volts except for the K155N1 Nixie drivers which is TTL on 5 volts. No microcontroller here.... It looks like crap having different colored random sized pcbs and so...The project is documented athttp://dangerousprototypes.com/forum/viewtopic.php?f=62&t=4735#p45823

author: SLJ
author_rank: Frequent Contributor
timestamp: January 12, 2016, 03:59:42 pm
content: Quote from: VK5RC on January 09, 2016, 12:35:18 amI like it. "It's always 57 somewhere".

author: lausvi
author_rank: Unknown
timestamp: January 12, 2016, 05:37:48 pm
content: This is currently my only working Nixie-thingy: a Philips PM2423 Digital Multimeter. It has AC/DC voltage and resistance measurements in 3.5 digits. Some more info in here:http://www.glowbug.nl/neon/PM2423.html. It's a bit limited but I have always liked it's slim look.It has two more indicators on the left-hand side next to the display: negative polarity, resistance measurement mode indication and '1' for the .5 digit.Couldn't find any references on the precision but seems to be running pretty good.

author: VK5RC
author_rank: Unknown
timestamp: February 01, 2016, 09:51:42 am
content: I loved the 5245L when I saw it and found a 'dead' one for a good price, one fuse later and she is glowing! A bit of spit and polish needed.

author: HAL-42b
author_rank: Frequent Contributor
timestamp: February 01, 2016, 10:14:20 am
content: You can't make a Nixie Tube current load and put a nasty keypad on it! You need a proper rotary dial.

author: Cubdriver
author_rank: Unknown
timestamp: February 01, 2016, 04:03:06 pm
content: Quote from: VK5RC on February 01, 2016, 09:51:42 amLoverly. A 5245L was my first nixie equipped test box. I blame it for the rest that have since come into my possession.I figure there are farworsethings I could be blowing my $$ on...-Pat

author: matseng
author_rank: Frequent Contributor
timestamp: February 02, 2016, 07:57:07 am
content: Quote from: HAL-42b on February 01, 2016, 10:14:20 amHm... Yes, I think I actually agree with you. Unfortunately I don't have a rotary dial in my otherwise rather ample junkboxes and the ones I can find at local auction sites are classed "as antiques" and have asking prices approaching $200. :-( But if I a rotary phone just happen to more or less just fall into my lap I'll retrofit my CC load - I promise.

author: BU508A
author_rank: Super Contributor
timestamp: February 02, 2016, 07:56:01 pm
content: Hi,this is my Nixie Digital Multimeter UGD 51 from Rohde & Schwarz. Based on the datecodes on some TTL IC I think it was build in 1974 or 1975.It is a real nice meter and very seldom.Enjoy the pictures.Edit: This is the data sheet for the UGD 51, sorry, but I have it only in german:https://www.dropbox.com/s/5n1okvd3nhbgfqn/UGD_51_Datenblatt_234051.pdf?dl=0

author: HAL-42b
author_rank: Frequent Contributor
timestamp: February 03, 2016, 03:19:09 am
content: Tubes ICs and Dzus fasteners on the front panel. Seems rather like some sort of aviation gear

author: VK5RC
author_rank: Unknown
timestamp: April 17, 2016, 12:50:04 pm
content: A nixie tube clock Nixies have developed some cathode poisoning, so I decided to have a go at 'cooking' it off as per 'tube-tester' Dieter'shttp://www.tube-tester.com/sites/nixie/different/cathode%20poisoning/cathode-poisoning.htmThe voltage discharge curve on a Nixie is a bit tricky so I used a LR645 (up to 400V in 10V linear regulator) and built a constant current source. So far using about double the data sheet max I (2x2mA) has cleaned a "2" in a IN14 CCCP tube.LR 645 Data Sheethttp://ww1.microchip.com/downloads/en/DeviceDoc/LR645%20A062113.pdfPic below 180V DC into current controller, 4.4mA, 163.4V out.

author: Cubdriver
author_rank: Unknown
timestamp: April 17, 2016, 04:21:29 pm
content: Rob, that's great!Another useful tidbit learned here to tuck away for future reference. Keep us apprised as to how long it ultimately takes, and how well it works when put back in the clock.-Pat

author: VK5RC
author_rank: Unknown
timestamp: April 19, 2016, 09:21:28 am
content: I have posted a few photos and a description of my Nixie rejuvenation experience athttps://www.eevblog.com/forum/repair/rejuvenating-nixies-some-comments-photos/msg922119/#msg922119It works well , go for it fellas ( and gals ).

author: richfiles
author_rank: Regular Contributor
timestamp: April 24, 2016, 07:40:49 am
content: Here is the Sony Sobax ICC-600W I restored. On the shelf, it's the black and silver machine next to the blue and white machine.In addition, I have a Commodore 512 and it's Casio equivalent, A Monroe 925, and A Remington 1259S, all using Nixie tubes. I can't recall if any others are using nixies, however, of special note (and NOT using Nixies) is my Smith Corona-Marchant Cogito 240 SR. It uses a CRT instead of nixies, but is absolution amazing anyway. It was made in 1965, and uses discrete resistors and diodes for it's logic. Transistors are generally reserved for line driving, inverters, and flip flops. Some of the other calcs use VFDs or panaplex displays.The Canon 163 also uses Nixies.

author: richfiles
author_rank: Regular Contributor
timestamp: April 24, 2016, 07:46:19 am
content: I built my PC case from a 1939 Philco radio cabinet, and installed a nixie clock in the front (those were postal box doors). The radio was long gone when I found the case. I've been wanting to mod it with a dekatron spinner that spins to drive access activity, and I've already added a seconds display to the second window!In addition, I have six nixie tube/thyratron decade counter/dispaly boards from a 1961 TUBE based ANITA Mk7 calculator.

author: Arhammon
author_rank: Contributor
timestamp: April 27, 2016, 12:37:08 pm
content: This is my 5.5 digit(6.5 digit in millivolt range) Soviet multimeter. Based on i8080 compatible CPU. It has segmented nixie? display. It looks like a VFD but is powered by 200 and 133 volts.Display. Fortunately, this is not my photo.

author: richfiles
author_rank: Regular Contributor
timestamp: May 09, 2016, 08:16:23 am
content: Quote from: Arhammon on April 27, 2016, 12:37:08 pmLooks like it's probably a Soviet variant of a Panaplex display. My Monroe 344 Statistician uses a genuine Panaplex display. They were filled with neon gas, and worked very much like a nixie tube, except segmented, of course. They were generally multiplexed. Mine works perfectly fine. It's just displaying an error cause the four "D" size batteries in it are nearly dead. it flashes the screen when batteries are low. These probably just need some batterizers**cough** or some such bullshit **cough**, cause it's now too low to do anything!Don't forget to check out Dave's teardown of a sister model to this one, branded under the Compucorp name.

author: Martin.M
author_rank: Frequent Contributor
timestamp: May 14, 2016, 06:32:19 am
content: the restoration of my Systron Donner Counter 6053 is done, except I am searching for a new orange front glass, the old is rotten.Here the oldie is counting a sine 1,25GHz delivered from my SWOB. (It can count up to 3GHz, a very fast counter)It would be possible to enhance 2 nixies more by plugging them + 7 IC and to do 2 bridges, but a resolution of 10Hz in GHz mode requires for shure a external clock feed from a rubidium.greetingsMartin

author: richfiles
author_rank: Regular Contributor
timestamp: May 14, 2016, 06:54:55 am
content: I am actually really sad about the first nixie tubes in my life... They are sadly long gone...When I was a kid, I used to ride with my dad in the tractor when he was working in the fields, and the corn/soybean planter was equipped with a counter in the tractor cab that used nixie tubes to show the seed flow rate. It quit working ages ago, and then he got a bigger, better planter. At some time between me being a kid, and me realizing what he had... it had been removed and discarded.I can't even find a decent picture of one, and my Google-fu is failing me...I wanna say it had three digits. I also recall that it had one of those sonalert style buzzers that you could twist to adjust the loudness. That was to notify you if your seed flow rate was too high or low. I can't recall how the rate was set. Whether it was pre-sets, analog, or a press to match? I dunno? It's been too many years. It would have been the 1980s when this still worked.I wish he had thought to let me take it, but it just didn't happen. Seeing all these cool nixie tube counters reminded me of it.

author: richfiles
author_rank: Regular Contributor
timestamp: May 19, 2016, 03:33:49 am
content: So, I did a little more research, and once I found the magic words (for Google), I FINALLY found that seed flow monitor. it was an International Cyclo 400 Planter Seed Flow Monitor.My memory recalled a lovely glowing orange tube... That much is true, but it turns out it's a Numitron tube, not a nixie. These were seven segment displays, but instead of LEDs, each segment was an incandescent filament inside a glass tube. It was an easy way to get a digital readout with a 12 volt DC power source, and not need to generate high voltages. The catch, of course, is that the filaments can burn out. The tube did not display the count. It only displayed the row selected (using the "Step" switch). It checked the flow rate based on three presets, and would use the lights on the left to indicate normal seed flow, or if the flow was high or low. The A, B, and C settings would have been used for general flow setting, and the "Auto/Manual" switch I think scanned through each row automatically, or held till you manually stepped it.The crazy thing, is since people STILL use the old Cyclo 400 planters from the 1970s for regular use... These still sell on eBay from time to time for $200 or more! Yikes! Farm equipment never dies... It just keeps getting maintained or passed to the next farmer.

author: Cubdriver
author_rank: Unknown
timestamp: May 19, 2016, 04:31:09 am
content: Must-not-start-searching-out-things-with-numitronsActually, I've been pretty good - it's been a few weeks since I bought anything with nixies in it!(Though I am supposed to be picking up a Tektronix 310 scope tomorrow, so the tube addiction hasn't abated...)-Pat

author: richfiles
author_rank: Regular Contributor
timestamp: May 19, 2016, 07:16:46 am
content: It's odd, but theONLYnumitrons I'veeverencountered in thefield... ahem... have been in agricultural equipment. Pardon my pun...The only device I own that has a numitron is an item I picked up at a thrift/antique store a couple years back. It was CLEARLY a one off, fully custom gadget. It was clearly hand made. I don't recall the function, but it was some manner of equipment someone would have used in an agricultural setting. Obviously the other numitron I'd encountered was in the Cyclo 400 planter monitor I previously mentioned my father having in his tractor when I was a kid.Even though this is primarily nixies, I'll try to remember to get a shot of the device next time I am at my storage unit.I suppose, it makes sense, given the fact that I live in an extremely rural location. While test equipment, lab equipment, and general digital devices are the first things that typically come to mind when one thinks nixies and numitrons... There really aren't any such industries locally. Best option would be the testing lab I work at, and they don't have any electronic equipment much older than 1980s. They actually keep their equipment reasonably up to date, at least by terms of usability and accuracy.The cutting edge in technology developing in an area such as where I live, was bound to be the latest and greatest in farming machinery. In the 1970s, most rural families likely had a radio or two,oneTV, not necessarily even a color model, and nothing beyond those two items more complex than your typical kitchen appliances and an electric clock (almost always in the kitchen, it would seem)... Yeah, the best tech was gonna be the fancy accessories in the newest farm equipment. Local banks might have made the switch to electronic calculators, but many small banks would still be using mechanical adders, and a family might have eventually got one of the new-fangled pocket calculators, once they dropped below $25... Half novelty, and half to make tax season and managing the budget less of a burden. Given the garage sale findings when I was a kid... People were just as likely to still just have mechanical calculators back then.We got digital seed flow monitors in the 1970s. We had even more digital readouts in the tractors in the 1980s. Ground speed radar, GPS, and auto "row drive" were introduced in the late 90s and in the 2000s. Now there are even driverless tractors (both follow the leader and fully autonomous types). Agriculture is always at the cutting edge. Small time farmers just get the hand me downs!We were using that little numitron equipped flow monitor through the 80s... Maybe even into the 90s. My grandmother bought a few houses in town in the mid 1970s, when realestate was low. She rented those out for years, and then sold them in the 90s... Westillhad pre-owned tractors!I suppose, tho point of my long and rambling mental wanderings, is that devoid of any tech industries, the only real tech industry in my local would have been agriculture itself. That's why I only ever find ag equipment with these retro display technologies... All my goodies have to come by way of eBay and exorborant expendetures!RIP wallet!

author: VK5RC
author_rank: Unknown
timestamp: May 19, 2016, 11:36:39 am
content: A bit of a ' fixer up' hopefully nothing too serious.@Cubdriver, I think I can hear the numitrons calling you! HiHi!

author: Gyro
author_rank: Super Contributor
timestamp: May 19, 2016, 11:54:06 am
content: QuoteNumitrons were widely used in Petrol (gas) pumps in the UK until relatively recently (in the last decade anyway) they've all gone LCD these days.

author: SeanB
author_rank: Super Contributor
timestamp: May 19, 2016, 05:03:45 pm
content: Military moving map display, with a board on top driving the display. Serial data in to a whole load of shift registers, then a transparent latch and finally the lamp drivers, a whole load of CD4050 buffers. We did convert a few to LED displays, using a small PCB sandwich and a cordwood construction to fit in place of the original numitron sockets, and using the existing wire leads. Think of putting 10 1/8W resistors in the space normally occupied by a low profile connector, and the 2 PCB units and the solder in pin sockets used to plug in the display. Then wire up the whole board with the 20 odd displays, place in the housing then find out they are way too bright. Solution, other than to remove the boards and replace the 180R resistors with 330R ones ( I was not involved in the design, just the helper in putting them together) was to use a pair of 6A diodes in series in the common lead from the display, to drop 1V2 or so, and drop the current. 6A diodes, as the display current was in the order of 5A on full brightness and with display test pushed in.

author: kultakala
author_rank: Regular Contributor
timestamp: May 19, 2016, 05:29:48 pm
content: I have no measurement equipment with nixies, but my old Casio fx-1.Here in front of modern LED technology.

author: bitseeker
author_rank: Super Contributor
timestamp: May 19, 2016, 06:04:49 pm
content: Quote from: VK5RC on May 19, 2016, 11:36:39 amAh, so you were the one who got it. Congrats. I look forward to your thread about its revival. I have its bigger brother that I haven't yet torn apart.

author: Cubdriver
author_rank: Unknown
timestamp: May 19, 2016, 06:21:22 pm
content: Quote from: VK5RC on May 19, 2016, 11:36:39 amThose 5221s are cute little buggers. Fingers crossed that you bring it back to life with minimal effort.QuoteRob, you're NOT helping here!!!-Pat

author: richfiles
author_rank: Regular Contributor
timestamp: May 19, 2016, 10:48:45 pm
content: Quote from: kultakala on May 19, 2016, 05:29:48 pmI love it! I have a Sperry-Rand Remington 1259S, which is a rebadged Casio fx-1. Interesting details about this calculator's internal architecture, is that it is actually a programmable chip set, but rather than allowing the user to enter user generated programs, most of the scientific function keys at the top performs a ROM encoded sequence of actions to actually go through the math to work out those functions. This results in the beautiful "numerical neon dance", as I call it. The longest function to calculate appears to be the cube root. I LOVE watching this thing calculate! Check out the video of those nixies!

author: tautech
author_rank: Super Contributor
timestamp: May 20, 2016, 12:45:11 am
content: Not mine...just a site I stumbled upon.AVO nixie clockhttp://www.bad-dog-designs.co.uk/testclocks.html

author: bitseeker
author_rank: Super Contributor
timestamp: May 20, 2016, 02:22:21 am
content: Quote from: richfiles on May 19, 2016, 10:48:45 pmWow, I've never seen a calculator like that. It is fun to watch it go, especially the way the decimal point flies back and forth. The cube root does take quite some time. All that video needed were some cheezy sci-fi sound effects to go with the computation.

author: kultakala
author_rank: Regular Contributor
timestamp: May 20, 2016, 06:39:04 am
content: Quote from: richfiles on May 19, 2016, 10:48:45 pmYes, i love it too. Nixie tubes in general are very nice... i use the fx-1 only at rare intervals but it looks cool.And the cube root function usually lasts exactly 16 seconds. Dont know how many still exists but i hope mine will keep working for quite a while.

author: Martin.M
author_rank: Frequent Contributor
timestamp: May 30, 2016, 08:53:34 pm
content: the next restoration,I will name them Plus & MinusgreetingsMartin

author: Martin.M
author_rank: Frequent Contributor
timestamp: May 30, 2016, 09:18:27 pm
content: Quote from: tautech on May 20, 2016, 12:45:11 amin my eyes that is a destroying of old instrumentsgreetingsMartin

author: guido
author_rank: Regular Contributor
timestamp: May 30, 2016, 10:18:47 pm
content: 5.5 digit meters with Panaplex displays.

author: richfiles
author_rank: Regular Contributor
timestamp: May 31, 2016, 12:53:42 am
content: So, remembering my dad's old seed planter monitor (with the numitron tubes) reminded me of another agricultural dohickey™ I found. I promised next time I got out to my storage unit, I'd get photos. Before I get into that, here is an instrument with actual nixie tubes. Sadly, it was low in the stack, and I couldn't be bothered to unstack a 5 foot tall stack of rack mount instruments to snag it from the third to bottom position. I'd have plugged it into my car otherwise. Rest assured though, that it works. The unit is used for testing synchro transformers, and you use the buttons to advance it by 5° at a time, or to reset it to 0°. Pretty straight forward. The Nixies display the degrees of rotation that you are testing the synchro at.It's a Gertsch Synchro Bridge, used in the manufacturing and testing of synchros. I actually have a thread on emulating synchros, to drive aviation equipment. That project is slow going, we shall say...I'll get to it again. I did snag a resolver standard and a resolver bridge from he stack (thankfully near the top). No, they don't have nixie tubes, or even panaplex or numitron tubes, but they do have tape displays. I am considering salvaging those to make into tape meters fro my Kerbal Space Program controller. Tape meters are SO HARD TO FIND! (those are meters that have a fixed pointer, and a scrolling reel of "tape" marked with numbers that moves by to indicate). These resolver bridge/standards have a rather complex switch arrangement that provides absolute position feedback for where the tape is at, for 72 absolute positions... Not bad!Now, I promised some numitrons! This is the Harvestall "Topdrop" Integrated monitor and control of differential temperature. I suspect it was built as some sort of demonstration unit for some manner of crop drying monitor. The chips have mostly 1978/79 date codes, and I suppose most digitally controlled anything was fairly new back then, at least in the ag industry. This unit once had a cover, as evidenced by latching hardware on either end. Likely, it had a cover that closed the whole demo unit, and had a handle at the top. The cover was not with it when I found it.This contraption looks hand made to me, with a few manufactured components. The PC board was professionally manufactured. Much of the rest looks custom. Again, no idea how this would have been used to demonstrate the product they were selling. I don't know the nature of the demonstration, or how it worked, but there is a fan in the unit, and lights inside the assembly at the left. There are two temperature probes (not sure if thermistor or thermocouple). As per the function, it seems to monitor an internal temp and an ambient temp, and then show the difference, as far as I am able to tell.No idea what the switch is selecting.I do suspect the unit was related to grain drying. The object to the left is shaped like a grainary. For city folk, that's a concrete or steel building, typically cylindrical, that is used to store seeds and grain. They are filled by dumping the seed in through a hole at the top, and unloaded through a chute at the bottom. A lot of farmers use grain driers to dry the seed, which nets a higher payout for selling, as dry seed is lighter to transport, and has a lower chance of spoilage (mold, etc). There is of course, a cost benefit ratio in drying the grain yourself. The logo made from two arrows resembles a granary. The contraption tot he left resembles a granary. The function seems relevant to drying... It seems like that's probably what they were selling this for. I also LOVE that company's logo. It's got a very "Egyptian" theme! Don't know why I dig that.Doesn't exactly scream "Minnesota", eh.**EDIT**Doing a little digging, it seems that Harvestall had been marketing a method of "chillcuring" grain. Rather than drying grain with heat, they were drying grains cool. They claimed it was more energy efficient, and was easier on the seed than hot air drying. They operated through the 1960s or 70s, and under the name Harvestall from 1977 until 1982, and continued some form of operation up to the 90s. The industry was heavily pushing hot air drying of grains, and agriculture got hit pretty hard in the 1980s by high interest rates and low profitability (at least in the US).The controls make a little more sense now. They regulated airflow to maintain a lower temperature by drawing heat off with the moisture pulled away. Or something like that, I guess. The unit's switch has differential temperature detection points (in auto mode) for 0°, -4°, -8° (presumably F°, since this was marketed in the US). I suppose this likely regulates the fan. The only heat (besides efficiency losses of the electronics and mechanical systems) were a series of infrared lamps that were used for pre-drying intake air if the external ambient air conditions were unfavorable for drying. Their process didn't use kilns or propane for extreme drying, like how most grain drying is done. They mimicked the natural convection flows of old style corn cribs (a style of building for storing corn that has gapped slats instead of solid walls to allows air to flow through it). The more you know!Further reading tells me the guy (Sylvester Steffen) who ran this business was into some weird pseudo-religious q/whack job new age thingamawhatsit that had him makingamazingstatements like how people are making such a big fuss about the right to life with the abortion debate... but what about all the wasted life from improper seed drying? What about the seed's right to life?SERIOUSLY!He was touting energy savings and drying techniques for seeds that were "easier" on the seeds, not for the sakes of energy savings and increased yields, but cause it was morally necessary in the fight to convert as much energy in the universe into living molecular organisms and to fight against entropy, staving off the chilling of our mantle! This guy...I can't stop laughing at this guy! That's the freakin' 70s for ya! Whack job new age nutters!On a side note, totally explains the pyramids and the whole Egyptian theme... New age nutters freakin' LOVE pyramids! The actual reason they used the image of a pharaoh and the pyramids, is a reference to the "dream of 7 years of plenty, followed by 7 years of famine" told in the bible. In the story of the pharaoh, he built granaries to store food when it was growing well, so Egypt would not go hungry in the years that would follow, after Joseph interprets his dream. So I guess the whole granary thing kinda sorta makes sense? ish?Now I'm REALLY glad I found this old demo tool... Satisfies my love of vintage electronics, AND gave me an epic laugh!

author: BillyD
author_rank: Regular Contributor
timestamp: June 15, 2016, 04:01:46 pm
content: Just stumbled onto this on youtube, a guy who actually manufactures nixie tubes. Amazing to watch.https://www.youtube.com/user/daliborfarny/videos

author: Enigma-man
author_rank: Regular Contributor
timestamp: July 26, 2016, 04:26:09 pm
content: I came across this site a few months ago and decided to join yesterday. I was glad to see this thread and see some vintage Nixie equipment still operational.Some unusual and slightly bizarre pieces to say the least.@BillyD:I saw the video. Dalibor F. has some serious engineering skills. Is there a video of him making the cathodes ? Now that is something everyone wants to see.At one time I had a B&K Model 281 2.5 digit multimeter as seen on a previous page. The tubes broke after it fell from my workbench and that was the end of it.Good to see a pic of one working again. Made me smile.Anyway, I have only one piece of Nixie gear as of today. It's an Eldorado Electronics Model 1820 Digital Meter which measures DC Volts, DC Current and Ohms.It does not qualify as a true multimeter due to the lack of any AC measurement capabilities, but no big deal. This unit is from the early 70's and is RTL logicas can be seen from the 700 series IC's. The analogue board is mounted underneath the logic board and appears to be a dual slope design which was common for this timeline.There are no integrated circuits in the analogue section. It is all discrete components, some obsolete such as the dual JFETS made by Intersil.A buddy of mine gave it to me and he didn't even know if it worked or not. It sat in his basement workshop for years...It did work when I powered it up, but with no input the display went crazy and would not settle down.I had an idea as to what it might be. Back in the early 70's there was not too much RFI. Computers were running at 1 or 2 MHz...Last year my buddy gave me a Fluke 8500A with a similar problem which was solved by installing an AC filter module.This is what the unit looked like when I received it last month. Spotless inside and not beat to death. There are a few nicks here and there onthe front panel as would be expected from a piece of electronic history from the early 70's. This unit and the Fluke were from government installations and reasonablywell cared for.After removing the top cover, no AC filter was seen. There was a line cord going to a switch and fuse. I removed the line cord and put in an AC filter module whichsettled things down considerably. One learns from experience and I had an idea the wild display on the Eldorado was related to RFI coming from everything in the house !The unit had and has other problems. It zero drifts after a period of time. Without a service manual it will remain unsolved. I did make some changes as seen in the pic of thelogic board.(1) The AC input filter module(2) 470uF/35V(3) 15000uF/10V(4) 10K 20 turn trimpot to adjust the 3.6V reference. (It was at 3.52V originally)(5) Not changed, but a previous repair attempt(s) by someone else. Pads were missing on both sides of the board.Not shown was a 6.4V temperature compensated zener on the analogue board underneath that was open and you guessed it, now OBSOLETE.It was a reference for the ohms section. I had two 6.2V temp compensated units from a failed Tektronix 7A12 vertical module from my 7704A scope.Replaced diode and readjusted the ohms section trimpots accordingly.Without a service manual the drift problem and residual .035 volts added to the input will have to remain for now, but that is okay.At least it works and will serve as a piece of nostalgia from a bygone era.I forgot to mention the Nixies. They are Phillips ZM1000 for the digits.I may have something else to show by week's end courtesy of my generous buddy.

author: bitseeker
author_rank: Super Contributor
timestamp: July 26, 2016, 07:10:35 pm
content: Welcome, Enigma-man. That's a good looking meter! Thanks for sharing it and I look forward to seeing the new arrival.

author: tautech
author_rank: Super Contributor
timestamp: July 26, 2016, 10:48:20 pm
content: http://www.sphere.bc.ca/test/nixies.html

author: VK5RC
author_rank: Unknown
timestamp: July 27, 2016, 11:10:13 am
content: @Enigma-Man , watch out this is a very dangerous part of electronics, not from the HV but the TEA (test equipment addiction esp Nixie) poor old Cubdriver is too far gone now for saving! HiHi

author: Cubdriver
author_rank: Unknown
timestamp: July 28, 2016, 01:54:15 am
content: Indeed! 'Tis a very slippery slope that, thanks to the wonder of ebuy, can cause great pain to both your credit card AND your friendly UPS/FedEx/USPS/<insert parcel delivery entity of your choice here> carrier. They are typically used in older gear that was built back in the days when test equipment could also function very effectively as ballast or an anchor if necessary.-Pat

author: Gyro
author_rank: Super Contributor
timestamp: July 28, 2016, 12:36:02 pm
content: More for the collection...My old Advance (later Gould) 15Mhz Timer counter:Nice solid internal construction:And nice well though-out access for servicing:As there are a few Panaplex displays showing up in this thread, here are a few more: My collection of Datron meters together with my Philips PM6622 Timer counter, also with a nice Panaplex display. Sorry, the displays look a bit washed out due to the flash, much brighter in reality.

author: AF6LJ
author_rank: Unknown
timestamp: July 28, 2016, 02:13:15 pm
content: Nice

author: Arhammon
author_rank: Contributor
timestamp: July 28, 2016, 04:17:46 pm
content: Philips's panaplex display looks fantastic!

author: Enigma-man
author_rank: Regular Contributor
timestamp: July 28, 2016, 10:04:09 pm
content: @Gyro:Very nice,indeed.Those Datron units look like they have Beckman seven segment displays.I have four 1.5 inch high Beckman's that came out of two digit speedometer displays once used in diesel locomotives.Long ago, I made a pc board for them but haven't yet put them to use. A genuine, made in Japan, Burroughs Nixie is shown alongside for size comparison.The Nixie was bought in the late 70's at Radio Shack and is unused with all its leads twisted together.A simple 3.5 digit voltmeter could be made using an Intersil or Maxim 7107 which can drive these through inverters and MPSA42 transistors.I suppose some other home brew piece could be made based on the above chip.

author: bitseeker
author_rank: Super Contributor
timestamp: July 28, 2016, 10:13:38 pm
content: What's the sepia-colored staining on the PCB?Quote from: Gyro on July 28, 2016, 12:36:02 pmVery nice construction, indeed.QuoteQuoteI really like the look of the Panaplex displays, but don't have any yet. What's a reasonable expectation for lifetime? I've seen others with, for example, Datron equipment and the displays have gone bad. Are they better, worse, same as VFD?

author: Cubdriver
author_rank: Unknown
timestamp: July 28, 2016, 11:15:38 pm
content: I'd expect a panaplex to have a lifetime similar to that of a nixie tube, as it's for all intents and purposes the same thing - a neon display. They might be more susceptible to mechanical failure as the face plate is bonded to the main housing, but barring that issue I'd expect them to last a very long time.-PatEdit to remove extra word. Inglish, as she is goodly speeked and writ.

author: Enigma-man
author_rank: Regular Contributor
timestamp: July 29, 2016, 12:31:01 am
content: Here's a few pix of a capacitance meter made by me in either '88, '89 or 1990.It uses smaller Beckman displays. The pix were taken yesterday. It doesn't get a lot of use but it still works...There was no internet back then. Only data books and application notes and good old do-it-yerself motivation.Today everything is Arduino, Raspberry Pi or Beagle something or other. Not as much fun as to me as the hands on discrete parts project.To each their own, I guess...

author: Cubdriver
author_rank: Unknown
timestamp: July 29, 2016, 12:51:16 am
content: Nicely done!!-Pat

author: bitseeker
author_rank: Super Contributor
timestamp: July 29, 2016, 12:54:00 am
content: Very cool displays, Enigma-man!

author: VK5RC
author_rank: Unknown
timestamp: July 29, 2016, 10:06:26 am
content: Very nice construction, the PCB home made as well I suspect,

author: Gyro
author_rank: Super Contributor
timestamp: July 29, 2016, 10:13:18 am
content: Beautifully implemented Enigma-man! I particularly like the use of smaller displays for the annunciators. And my type of 'fun' engineering too.Yes, all the pre 106x Datrons used socketed Sperry / Beckman / Babcock/ SP3xx displays. The mV / V etc annunciators were done with dim lamps behind transparencies. They are also a 'micro free', no batteries, no eproms, just discrete analogue and socketed logic, making it possible to maintain them more or less indefinitely. They still achieve 0.01% class accuracy and stable 1uV resolution. Well worth grabbing if you see one cheap (avoid the 105x 5 1/2 digit series, it uses an unobtainium custom PMOS counter logic chip and a very touchy triple slope conversion circuit).I think it was sad that adopted a custom panaplex display on the later models, but every major manufacturer did the same, but it is a definite weakness when it comes to restoring older units. Remember though that a lot of the 106x meters on the market have been left on 24/7 for decades.@bitseeker:QuoteNo idea, it's on the surface and definitely not heat related, my guess is either flux residue or lacquer. It's not sticky and I've never tried removing it. BTW did you notice the big beehive trimmer cap up next to the glass encapsulated crystal in the top right corner? That's the frequency trim.QuoteLife is certainlywaybetter than VFD - particularly due to absence of uneven brightness loss. The Sperry / Beckman spec states a blanket 10 years with a note that operating at Maximum rather than Typical ratings can reduce life. In practice it's difficult to get them dim enough, even at Minimum specified current (They were specified at 200ft lamberts () and a viewing distance of 40ft). I suspect that minimum current drive increases their life even further. Like all cold cathode tubes, the cathodes will splutter if overdriven.As you say Cubdriver, they are more mechanically sensitive than anything, the front glass is bonded as are the pins, but I think they use glass 'frit' seal (as cerdip packages). There are also internal getters (the little ring structure at the bottom) to mop up gasses. Given that many of the ones still in use are 40+ years old, long term leakage doesn't seem to be an issue.@Arhammon: Yes the Philips one is particularly nice, it's a multiplexed display (multiplexing does seem to look better, maybe because it drops the brightness below what can be achieved at minimum current in static drive). It looks a lot nicer than the LEDs they used on later counters.P.S. I should probably qualify that multiplexed display comment. What sets the minimum current spec of the display is having sufficient current density to light up the entire surface of a segment. When multiplexed, the segments get driven at higher current, but for lower duty cycle. This seems to make them look dimmer and 'sharper'.

author: bitseeker
author_rank: Super Contributor
timestamp: July 29, 2016, 06:24:04 pm
content: Thanks for all the info, Gyro. The only regret will be my lighter wallet after having learned more about Panaplex displays.

author: Gyro
author_rank: Super Contributor
timestamp: July 29, 2016, 07:16:48 pm
content: At least you're in the US - you get much better pickings than we do!http://www.ebay.co.uk/itm/Beckman-3-Digit-Display-Panel-Panaplex-Model-SP-353-/162079434878?hash=item25bcafe87e:g:LtEAAOSwkEVXGSDF#shpCntId

author: bitseeker
author_rank: Super Contributor
timestamp: July 29, 2016, 07:54:44 pm
content: That's true.The pins are going every which way on the back of that display. Poor thing.And that's how it starts, right Pat? (Well, that's one way of many.)

author: Cubdriver
author_rank: Unknown
timestamp: July 29, 2016, 09:47:22 pm
content: Quote from: bitseeker on July 29, 2016, 06:24:04 pmYup. I have a half-assed search for Datron stuff on the 'bay, I will doubtless now be looking more carefully.-Pat

author: Gyro
author_rank: Super Contributor
timestamp: July 30, 2016, 08:55:16 am
content: One is glad to be of service.Maybe I'll do a teardown sometime, if pressed (better let this thread get back to Nixies).Chris.

author: VK5RC
author_rank: Unknown
timestamp: July 30, 2016, 09:39:33 am
content: BUILDING A THERMIONIC TUBE TESTER (V , V , I curve tracer)Whilst not a Nixie tube it is close, I have built and tested theuTracer3+ from foreverDOS. If you have a need for a thermionic tube tester I would recommend this as an interesting and high quality project, ultimately not cheap though.It comes as a complete PCB and parts kit with an great manual and an excellent website. You need to provide the box, a 19V laptop power supply, the 'pegboard' sockets and the tube sockets (these can get quite expensive).The uTracer is basically 3 power supplies (and Voltage samplers) in the one unit controlled by a serial port and a program on your computer,One low voltage variable , modest current continuous supply for the heater circuitTwo high voltage (boost SMPSU) relatively lower current supplies for the Anode/Grid,The tester does quite a clever trick in that in only actively tests for some milli-seconds at a time , so the SMPSU can supply up to a 200mA or so briefly up to 400V(from -50V if needed) !Wiring the multiple sockets is a bit challenging but made a lot easier by a wire stripper.Below are photos of the complete PCB, the inside wiring of the sockets and testing a 12BYA , note the hot filament and while HV is active a warning light is displayed.http://dos4ever.com/uTracer3/uTracer3_pag0.htmlNote No association other than happy customer!

author: bitseeker
author_rank: Super Contributor
timestamp: July 30, 2016, 09:28:49 pm
content: Quote from: Gyro on July 30, 2016, 08:55:16 amCould always start a "Let's see your Panaplex display equipment" thread. (Hint, hint, wink, wink, know what I mean, know what I mean?)

author: Enigma-man
author_rank: Regular Contributor
timestamp: July 31, 2016, 03:26:24 am
content: Boys and girls, today's show and tell is the following:Here is an HP 5221A four digit Nixie counter. It is in near pristene condition for a piece of equipment with date codesof 1967 and 1968. Some IC's have unusual codes. My guess is that this unit is from 1968 or 1969. It is absolutely spotlessinside and out. All components are original. Not bad for 48 years of age. The logic board has the upside down Nixies and thereis provision for two more digits on the gold plated pc board. The IC's are non-standard decade counters, storage and drivers.7400 series 7490, 7475 and 7441 or 74141 could be subbed but are not direct replacements and would require a piggyback boardif and when repair is needed.Judging by the condition, this 5221A didn't see a lot of use and could sit in HP's museum if they already didn't have some.The big and heavy piece of equipment which I thought was a frequency counter turned out to be a Gould K115 Logic Analyzer from around 1990.It has a 5.25 inch floppy with a diskette with that supposedly has a Z80 disassembler on it if it can still be read.One day I'll fire it up. No real use for it but it's in really good shape complete with cables.From Dr.Dobbs concerning logic analyzers"There's two problems with these big logic analyzers. First, the Gould machines weigh something like 80 pounds and take up roughly thespace of a midsize PC tower. You have to be pretty desperate — I mean motivated — to go drag one of these out and clear off a spot for it."I'm not desperate or motivated... I got it for nuthin' and he ain't kiddin' 'bout the weight...Back to the cutesy counter. Here's the pix.Mr. Sparky provides some comic relief.

author: Gyro
author_rank: Super Contributor
timestamp: July 31, 2016, 12:22:38 pm
content: Very nice Enigma-man. Nixies and HP have got to be a winning (and collectable) combination.I agree, it would be nice to see the other two digits populated, but I'd probably only be tempted to do it if you could find original pin compatible parts, it would lose some of its charm with a piggyback board. Hopefully a scrap donor unit might come along.Upside down Nixies are a bit of a rarity but they are shown on Dieter's Nixie World site here...http://www.tube-tester.com/sites/nixie/trade01-nixie-tubes.htmIt's areallynice site to go and browse, even if you don't have any of your own to play with. It also has useful Panaplex data too.It looks as if your displays are Burroughs B-5560 from the description.Oh, @bitseeker:Quote from: bitseeker on July 30, 2016, 09:28:49 pmNot a bad idea, give me a few days to take some pictures.

author: b_force
author_rank: Super Contributor
timestamp: July 31, 2016, 02:18:04 pm
content: What type are normally those small nixies?I like to use a few for a projects (hopefully there is a cheap Russian equivalent with a real five)

author: Enigma-man
author_rank: Regular Contributor
timestamp: July 31, 2016, 03:34:29 pm
content: @b_force:The answer to your question is go to Dieter's Nixie World link above and you will see there is nothing really "normal" about Nixie tubes.You will see different sizes and styles.If I were you, I would decide on a style after seeing what is available for purchase and budget if you have one.You may have to settle for what you can get because some in the list are rare. There appears to be a fairly good supply of Russian tubes.@Gyro:A piggyback board would only be temporary. I would use two machine sockets where the Nixie drivers would go and use a DIP header to attach the piggyback board.The upside down Nixies may take a while to find. Most likely things will remain as they are for now. The service manual showed the extra digits as options.If someday I do find a donor, the options will be done in a proper fashion.pmanning at smugmug.com shows his nearly beat to death six digit 5221A as received and after cleaning etc. I like the one I have better...https://pmanning.smugmug.com/Electronics/HP-5221A-Electronic-Counter/

author: Gyro
author_rank: Super Contributor
timestamp: July 31, 2016, 04:51:27 pm
content: Ah yes, I see. I was surprised that the footprints aren't industry standard but looking at Wikipedia, 54 series parts weren't around until 1964 and 74 series until 1966. They may be based on Sylvania (Edit: SUHL) parts (1963). That's quite a teardown pmanning did... 55 photos.It's a bit surprised that anyone bothered to order the counter without the 6 digit option. The cost difference should have been minimal unless HP loaded the pricing. Datron offered an extra digit resolution on the 1030 RMS voltmeter as a no cost option but that was just an extra driver chip as the Panaplex display already included the digit (actually according to the assembly drawing, the chip got unplugged after factory test!).

author: Enigma-man
author_rank: Regular Contributor
timestamp: July 31, 2016, 05:35:44 pm
content: @Gyro:All of pmanning`s restorations are like that, which is good for comparison. I suppose the best gauge for any attempt is opening up whatever it is andsee what`s there or missing, be brave and fire it up. If it doesn`t blow fuses or burst into flames you have reached the first step. How far one getsdepends on the "unobtanium factor".In the 5221A there are decade counters that are in TO-5 cans listed as IC2, IC3 and IC8. They are TTL with HP numbering.According to the Hewlett-Packard Journal 1967-08, the 5221A was introduced and was said to have readily available off-the-shelf Texas Instruments 74 series asreplacements. TI had their pinout, Motorola and others had their own. Not sure who won out but it was probably Motorola. TI went with the standard as I do have several74 series TI chips.The 5221A, four digit counter is listed at $475 US. There was also a time base upgrade option. I think I saw a price of $675 US for the six digit model with time base option, somewhere...Looking at schematics from HP equipment in the early 70's and comparing with a Motorola TTL Databook one can determine the following:1820-0055 is a 7490 decade counter1820-0100 is a 7441 decoder/driver1820-0707 is a 74141 decoder/driver (improved 7441)1820-0301 is a 7475 four-bit latch

author: b_force
author_rank: Super Contributor
timestamp: July 31, 2016, 05:37:54 pm
content: @ Enigma-manThanks.I am already familiar with nixes. I have a bunch of clocks (developed) myself.I was only wondering if people would directly know a specific type or so

author: Cubdriver
author_rank: Unknown
timestamp: July 31, 2016, 06:23:05 pm
content: Wow, E-man -That counter is in beautiful shape - looks like it came from us of the box yesterday. Mine looks like it went through the war in comparison (as you saw from the SmugMug pictures). I've gotten a replacement tube since the photos were taken, but haven't found the time to get it back on the bench to install it and for further surgery. It has some other issues, and I plan to try to clean it up more as well.For what it's worth, I looked up the prices in the 1970 HP catalog:5221A base model: $425.00Option 001 - 1 add'l digit: $75.00Option 002 - 2 add'l digits: $125.00Option 003 - Xtal time base: $100.00This all seems cheap to us now, but on a relatively inexpensive counter I suppose it was a pretty big nut at the time. It's also quite possible that many were using it literally as a counter (I think we're predisposed to always think 'frequency' here) and had applications that would never go over 9999 counts, thus not needing the extra digits at all.-Pat

author: Gyro
author_rank: Super Contributor
timestamp: July 31, 2016, 06:30:01 pm
content: Sorry Pat, I didn't realise it was your teardown!They really did load the pricing for those options didn't they.

author: Cubdriver
author_rank: Unknown
timestamp: July 31, 2016, 06:47:56 pm
content: Quote from: Gyro on July 31, 2016, 06:30:01 pmNo worries! Between forum screen names, first names in signatures and other account names, the connections aren't always obvious. (And, I don't recall posting that counter in this thread.)HP's stuff wasn't cheap, but if they manually reworked the boards to add the digits I could see it costing a pretty penny to retrofit the additional digits, even at the factory. The 'B' model of the counter, which as a base unit included the crystal time base, seemed to have been aimed more at the cheap (frugal?) frequency measurement crowd. It had 5 digits with an optional 6th, and IIRC more gating positions on the switch.-Pat

author: Enigma-man
author_rank: Regular Contributor
timestamp: July 31, 2016, 08:41:17 pm
content: @Cubdriver:I almost (not really) felt bad seeing the condition your 5221A was in when you received it and for that matter some other pieces you have.Sometimes one gets a really good one, like me for instance...Seriously, though I did feel bad and we learn something new everyday.

author: bitseeker
author_rank: Super Contributor
timestamp: July 31, 2016, 09:57:13 pm
content: E-man,That's a beautiful 5221A! It's the first time I've seen the A version with the default four digits. I started my Nixie adventure hunting for either a 5221B or its sibling the 5321B. The B version has five digits standard with an option for the sixth. The 5321 is a half-height (or thereabouts) and slightly longer/wider variation of the 5221. Both are nice desktop units.During my hunt, I discovered and acquired a couple of HP 5216A counters. This model looks like a wider version of the 5221 with seven Nixie tubes. I guess I should post a few pics here since I haven't yet gotten around to tearing it down for its own thread. Both units are a bit flaky. I just hope it's not the ICs that are bad since HP built in additional decoder states to blank the left-most zero digits.Pat,It's nice to see your fully-populated 5221. I guess I'll be picking your brain when it comes time to work on my 5216. As for the dead tube, I have yet to run across any available replacements. If I do, I'll be sure to let you know.Does the SmugMug gallery represent the current state of your 5221? Are you looking for other parts for it such as the logo, knobs, etc. to fully restore it?

author: Cubdriver
author_rank: Unknown
timestamp: August 01, 2016, 12:13:22 am
content: Bitseeker -I've been on the lookout for a B model as well (it has the better time base, among other things), and would like to find a 5321 of either flavor just for the variety. No luck so far, but I did snag another 5221 from the 'bay a few months back. It is a base model with only four digits, and hasn't yet been wrung out or photographed. It was modified by a previous owner and sports dual banana jacks for the input rather than the BNC it initially came with, so it's not entirely original. It's also not nearly as abused as the poor one shown in the SmugMug pics was...I did eventually find a replacement tube on the auction site; just haven't gotten to putting it in thus far. My best suggestion for finding a replacement is to set up a couple of ebay searches, one with its HP part number and another with its manufacturer's part number at least. Then be patient - they seem to turn up once in a blue moon. The Electro Instruments meter is presently occupying the bench, so it may be a bit before I get back to the 5221. If I should stumble on any replacement tubes in my travels I will point you towards them, or grab one for you if it's at a swap meet. It kills me when equipment like this is ruined so that people can make clocks when there are gazillions of NOS Russian nixies available that can be had inexpensively and without the murder of fine old test gear.I'll be happy to help however I can when you get to the 5216. I'm on the lookout for one of those as well; eventually one will turn up.Yes, the pictures in the gallery do show the present state of the counter. I'm going to revisit it and see what I can do to make it prettier, and would love to stumble upon a box of logo badges - they seem to be missing on a lot of instruments. I'm not sure if they fall/break off or if people are prying them off as keepsakes or something, but regardless of the reason it's annoying to me when they're missing! I do have some spare knobs from a swap meet buy a year or two ago, but need to excavate them from wherever they've gone off to to hide. My house eats things - this should come as no surprise to anyone who's seen the pictures of the bench area and the metro cart (wire shelving rack) with the test gear on it.It's nice to see this thread still alive and kicking!-Pat

author: Cubdriver
author_rank: Unknown
timestamp: August 01, 2016, 12:57:13 am
content: Quote from: Enigma-man on July 31, 2016, 08:41:17 pmI only just now expanded that thumbnail. Somehow I doubt that little tid-bit of knowledge is even in the same GALAXY as E=mc^2!Well, the condition winds up being whatever it is, and there are some things I've passed on due to the shape they're in, but in other cases depending on the rarity or cost, it's worth the roll of the dice to try to snag and restore something.-Pat

author: bitseeker
author_rank: Super Contributor
timestamp: August 01, 2016, 03:51:36 am
content: Pat,I've seen a few 5321 go by a couple-three months ago.This B modelwas a bit more than I wanted to pay and was missing the logo (yeah, what's up with so much HP gear missing that logo?). Earlier,this A modelI saw was complete and cosmetically good. The "blows fuses" issue didn't bother me, but it had the basic four digits and one or two tubes looked like they might be blown. So, I passed on it too.I'm not actively looking for one, so there's no worry about bidding against each other if you do see one. Once you get one, though, anything's possible.

author: Enigma-man
author_rank: Regular Contributor
timestamp: August 01, 2016, 03:55:27 am
content: Before getting off the topic of the 5221A, I thought it might be a good idea to extend the range to above 100MHz by connecting a homebrewECL divide by ten prescaler. I have ten 10138 counters that can be wired for divide by 2, five or ten. It would function as an inline device so the5221A would remain unmodified. A crystal oscillator as a timebase would be better than the AC line frequency divided by sixty as is now the case.

author: bitseeker
author_rank: Super Contributor
timestamp: August 01, 2016, 03:59:59 am
content: Funny you should mention that. I was thinking along those lines as well. It would be a non-intrusive way to keep these counters useful. The 5216 I have is a 12.5 MHz counter, so a /10 pre-scaler would make it a nice 125 MHz device.

author: Enigma-man
author_rank: Regular Contributor
timestamp: August 01, 2016, 04:15:13 am
content: @bitseeker:Glad you liked my 5221A. The prescaler would be easy to construct. The only downside is powering the thing with an external power supply.I suppose one could take +5V from the unit itself and run the wire through a perforation on the bottom plate.I wonder why the previous owner of Cubdriver's 5221 would modify it to accommodate banana plugs when all he had to do was hook up the jacks toa piece of BNC cable.It still serves the purpose and saves time by not having to modify/bastardize the unit.

author: bitseeker
author_rank: Super Contributor
timestamp: August 01, 2016, 06:52:21 pm
content: I'd be very interested in making a prescaler. Although I have an idea how counters operate, I don't have in-depth knowledge of their design and operation. Thus, mine will serve an educational function in addition to bringing them back to full operation and looking cool on my bench.On the 5221 and 5216, pin 3 of the digital recorder/printer connector provides 5V and pin 1 is ground. However, I haven't looked into the schematics to see if it could actually take a load. It's intended to be a 5V reference for the data lines. Nevertheless, if you took power from elsewhere inside the unit, you might be able to make use of the space around the card edge connector to run the wires to the prescaler. I'd be fine with just putting a DC jack on the prescaler or using a bench supply (got plenty of those).Regarding the banana plug modification, it's also odd that a simple BNC-to-banana adapter wasn't used. Although that counter sounds familiar, I don't recall how good of a job the owner did. Hopefully, it doesn't look bad.

author: Enigma-man
author_rank: Regular Contributor
timestamp: August 01, 2016, 07:40:32 pm
content: I think the prescaler for my 5221A would be a waste of time. With only 4 digits and no over range indicator, there's no way totell what the actual frequency is. When 1MHz is applied all I get is the rightmost digit showing a zero.I think my unit may have seen use as an event counter of some sort. When the switch is in "OPEN" position, it counts up until 9999 then goes back to zero.Not a big deal for me and the 5221A won't see a lot of use unless I can add two more digits in future. It's more of a show and tell item.It works as a frequency counter in a limited capacity.However, I will breadboard a prescaler then hand draw a pc board if you want one. It's not a complicated piece of hardware.I have close to 100 RCA CA3179 1.25GHz prescaler IC's. The only drawback is that they divide the VHF signal by 64 and the UHF by 256.The timebase of the counter would have to be modified to see the true frequency. A one or ten Hertz timebase would show the input signalas the result of the input frequency divided by 64 or 256. That's why I never used any of them.700MHz would show 10937500 on the counter.A calculator would give you the proper result 109375 X 64 = 700,000,000If I was making a kit, I would toss in a dollar store $2 calculator as an "Auxillary Display Device"...Getting ahead of myself here.

author: bitseeker
author_rank: Super Contributor
timestamp: August 01, 2016, 08:52:42 pm
content: Quote from: Enigma-man on August 01, 2016, 07:40:32 pmI see. So that might be why the B version has five digits standard.QuoteAs a show item, it's certainly easier to live with on the desk than a full rack width counter.QuoteThanks, very kind of you.QuoteYeah, that sounds like a pain.QuoteLOL! I'd probably hook up an Arduino to the digital recorder port and have it do the conversion for proper display. Of course, one could also do the division with a dedicated circuit.

author: Enigma-man
author_rank: Regular Contributor
timestamp: August 02, 2016, 05:51:49 pm
content: More seven segment Panaplex gas discharge displays...The small ones are made by Sperry. The two digit ones are SP-336 and three digit are EX-337.Sphere was asking $49 each for the three digit and $15 for the two digit. The Beckman 1.5" areshown for size comparison.Two Beckman DD-700 7 seven segment driver chips are on the foam as is a 1.25GHz RCA CA3179 chip. (Not relevant)Last but not least, the first IC I ever bought... A TI SN 7450P in a ceramic package with metal top dated 6626.I have quite a collection of vintage CPU's and memory devices as well.I have 25 Sperry flat pack RTL uL925's in an unopened package dated 6520.That's for another thread.I forgot to mention that the little red rectangle is a three digit multiplexed LED display. The digits are barely more than 1/10 inch high.Man, that is small...

author: bitseeker
author_rank: Super Contributor
timestamp: August 02, 2016, 09:26:14 pm
content: What are the triangles and squares that I see below the digits on many of these Panaplex displays?

author: richfiles
author_rank: Regular Contributor
timestamp: August 02, 2016, 09:31:14 pm
content: I think the triangles are intended to be decimals/commas, and the square bits at the bottom are likely part of the metal of the electrode... I can never remember if it's the anode... I wanna say the segments are the cathodes... Gah! I can never remember!

author: Enigma-man
author_rank: Regular Contributor
timestamp: August 02, 2016, 10:43:43 pm
content: Yes, the triangles are decimals. The small Sperry displays only had decimals while the bigger Beckman displays could be used in clocks since they hadthe colon as well as a decimal and bar to make a comma. I'll hook up the big ones to a voltage source as they are already in sockets and on the pc board.I don't have any sockets for the small ones but I'll see what I can do and post some pix.Actually, the small ones were used in my capacitance meter a few posts back so you could see them there.

author: Gyro
author_rank: Super Contributor
timestamp: August 03, 2016, 09:49:34 am
content: Yes, the triangles in line with the bottom edge of the digits are decimals. The triangle down at the bottom (between the rectangles) is a 'keep-alive' electrode; it is constantly driven at low current when the displays are multiplexed. This provides a ready source of ionization to ensure that the display can re-light quickly.The rectangular structures are spring contacts that make contact with the front glass. The anodes are actually a conductive coating on the inside of the front glass, if you look in the right light you can see the conductive areas, one for each digit. Having the anodes on the front glass means that the glow is concentrated on the front of the cathode segments, making them sharper (unlike nixies, there the various cathode shapes aren't terribly sure where the nearest bit of anode actually is).The circular ring around the leftmost rectangular spring is the getter, for mopping up unwelcome gasses.

author: Enigma-man
author_rank: Regular Contributor
timestamp: August 04, 2016, 10:52:32 pm
content: Here is a Nixie power supply I made to power the Beckman's. It is a 555 driving an IRF740 Mosfet. The coil is a Coilcraft100uH surface mount inductor. The other power tab is a fast recovery diode rated at 1200V and 8 amp. A bit on the overkillscale but who cares ? I have some and might as well use 'em. It put out 192 volts when I first turned it on and haven't adjustedthe voltage yet. The Beckman's take more current than Nixies do. I found some application notes from Beckman that I still keptafter all these years. The app note says 5mA.The display isn't as bright as it appears. It's the camera's fault.The Eldorado shows the voltage. Now to make something with the Beckman's...

author: bitseeker
author_rank: Super Contributor
timestamp: August 05, 2016, 12:22:48 am
content: Quote from: Enigma-man on August 04, 2016, 10:52:32 pmAt first glance, I thought you built a power supply with a Nixie tube display. The thumbnail of the Eldorado meter looked like it was the power supply's front panel and display.

author: Enigma-man
author_rank: Regular Contributor
timestamp: August 10, 2016, 04:43:07 am
content: Today's show and tell is a Fairchild 7050 3.5 digit meter with National NL-848 style Nixies.It's in pretty good shape for something made back in 1967 according to datecodes inside.Some minor issues resulting from shitty repair attempts like damaging the pc board, solder pads missing,but nothing too serious. It needed minor cleaning in and out. The unit is still reasonably well calibrated.When I hooked up my AD688 10V reference, it showed +10.02 volts. Not bad, but it was adjusted to +10.00VI found a service manual for it which reads Systron Donner Model 7050. It's exactly the same so it looks likeFairchild made them for SD. This is all RTL logic, some Fairchild types as as well as the old ul9XX series. Round cantypes for decade counters.It's pretty compact for what it does. Everything is on one pc board.The plus/minus and the 1 indicator are standard NE-2 bulbs shining through a square piece of clear plastic.Well, that's it for now.

author: Enigma-man
author_rank: Regular Contributor
timestamp: August 10, 2016, 09:27:00 pm
content: A few pix of the Fairchild 7050 circuit board after minor cleaning and isopropyl scrub on otherside of board.In my opinion, this was an underrated piece of gear. It is very stable and surprisingly accurate and is way more stable than the Eldorado 1820A.The service manual shows accuracy claims of .1% from 0.000 to 1000V... Not too shabby.I let it run all night and it still showed +10.00 volts this morning.It gets afor looks.

author: bitseeker
author_rank: Super Contributor
timestamp: August 11, 2016, 01:58:00 am
content: It's doesn't lookthatbad -- it's got Nixies!

author: bitseeker
author_rank: Super Contributor
timestamp: August 11, 2016, 02:30:07 am
content: Here are my HP 5216A, 12.5 MHz counters. The one on top is older, having an oval-shaped power socket, whereas the lower one has an IEC socket. The top one also didn't want to wake up today, so it gets its photo taken while napping.Suffice it to say, they both need an overhaul, but since that may be a while I figured I'd at least share a photo for the thread.

author: Enigma-man
author_rank: Regular Contributor
timestamp: August 11, 2016, 04:38:44 am
content: I hate you...Your two counters have a total of fourteen Nixies, while my 5221A has a measly, paltry four tubes, upside down rare types.Good to see one working and they are both in pretty good shape. Hopefully the napping one doesn't have a logic problem.Finding the problem would be easier than finding a replacement RTL chip unless you have a donor.

author: bitseeker
author_rank: Super Contributor
timestamp: August 11, 2016, 04:48:59 am
content: It took quite some time to find these in good cosmetic condition. They aren't that prevalent to begin with, regardless of condition. The Nixies are upside-down, though, just like yours. All the HP counters of this era have very similar parts, including the proprietary driver and decoder ICs.I suspect that the primary problem with mine is in the power supply, in particular, and all the ecaps, in general, since one doesn't always wake up and both, when they are awake, count and/or gate intermittently. Some of the digits seem a bit flaky, though.If there are failing ICs, I can either make one of the counters a donor (hence I have two of them), replace with standard ICs forgoing the blanking feature, or make a daughter board to restore the blanking functionality using standard logic ICs.

author: Cubdriver
author_rank: Unknown
timestamp: August 11, 2016, 05:03:48 am
content: My 5216A has begun its eastward journey; it should be here in a few days.Hopefully the gating problem it has won't be a show stopper. And thanks to bitseeker for pointing it out and not bidding against me! Now we can collaborate on fixing them.The pair of boxes holding ~200 pounds worth of gear I shipped home from CA last week arrived today too, hopefully unscathed. (If itisscathed, I've no one to blame but myself as I'm the one who packed it.) They contain more nixie goodies for the ever growing pile-o-projects.The first has a Dymec 2401C integrating voltmeter and a 2410B AC/Ohms converter (unfortunately the 2401 lacks a couple of boards needed to interface with the converter, but perhaps I can cobble something together as a substitute). The second has the 2402A DVM and 5360A Computing Counter I snared at the surplus place last December on the trip when I got the plague and didn't manage to ship anything home. They'd been waiting patiently on the shelf at the office out there since then. After searching since December I finally found a copy of the 2402A manual that was being sold by someone whodidn'tthink it was printed in platinum ink on gold leaf pages and want insane money for it. There are some pics of the 2401C and 5360A taken out in CA on the SmugMug site, but I don't think any of the 2402A are up.Now if I can just stay away from ebuy (there are a couple of more nixie, VFD and panaplex meters enroute, too) and swap meets and surplus dealers for a few years... And maybe reinforce the foundation here before the house starts sinking into the ground.-Pat

author: bitseeker
author_rank: Super Contributor
timestamp: August 11, 2016, 05:13:55 am
content: Quote from: Cubdriver on August 11, 2016, 05:03:48 amOK, Pat. I'll do my best to avoid tempting you going forward.Enigma-man will have to rescue the next 5216A from the landfill. Maybe he'll stop hating me, then.

author: Enigma-man
author_rank: Regular Contributor
timestamp: August 11, 2016, 05:18:22 am
content: I'll call McFly and see if he's free on Friday so we can again take the DeLorean back to '69 or '70, hijack another shipment destined for thelocal HP office and snag you a brand spankin' new 5216A...From the photo, the top unit looks like it has standard Nixies. Must be due to a reflection.You would have to change your power supply to accommodate standard 74 series devices and rig up a level converter in between . RTL needs 3.6V.I am assuming both have RTL devices or does it have a mixture of standard 74 series and HP's version of TTL ?

author: Cubdriver
author_rank: Unknown
timestamp: August 11, 2016, 05:19:03 am
content: Quote from: bitseeker on August 11, 2016, 05:13:55 amIt won't do any good. It would have showed up in my watching feed even if you hadn't mentioned it. What Ishoulddo (but won't, of course!) is turn off e-mail notifications.-Pat

author: bitseeker
author_rank: Super Contributor
timestamp: August 11, 2016, 05:23:11 am
content: Quote from: Enigma-man on August 11, 2016, 05:18:22 amYes, those tubes do seem to be oriented the other way. However, look above the tubes. You can see the edge of the PCB that they're mounted onto.QuoteI haven't gotten that deep into the details of these devices. Perhaps Pat knows.

author: Cubdriver
author_rank: Unknown
timestamp: August 11, 2016, 05:25:15 am
content: Quote from: Enigma-man on August 11, 2016, 05:18:22 amNope - they're the HP 1970-0025/Burroughs B5560 'Bat' tubes like those in the 5221/5231s.-Pat

author: bitseeker
author_rank: Super Contributor
timestamp: August 11, 2016, 05:25:37 am
content: Quote from: Cubdriver on August 11, 2016, 05:19:03 amYeah, that wouldn't help in my case. I found that I see new items faster than eBay can email me, so I don't even bother turning on those notifications anymore.

author: Cubdriver
author_rank: Unknown
timestamp: August 11, 2016, 05:47:56 am
content: Quote from: Enigma-man on August 11, 2016, 05:18:22 amI just took a quick look through the manual and at the schematics - I think it's 74XX and HP TTL - all the ICs I saw seemed to be fed with a 5.1V supply and nothing else. Unfortunately I don't yet have an 'HP to real world part number' decoder ring yet, and by and large the stuff I've had to go into and work on ain't had none of these here newfangled aye-sees in it, so my HP IC-fu has not yet been developed...-Pat

author: bitseeker
author_rank: Super Contributor
timestamp: August 11, 2016, 05:55:29 am
content: No worries. We'll just have to get up to speed during our co-op restoration.

author: Cubdriver
author_rank: Unknown
timestamp: August 11, 2016, 06:00:23 am
content: Quote from: bitseeker on August 11, 2016, 05:25:37 amI start to run into 'problems' when I'm bored and start doing random searches of test equipment. That's how I have several other-than-HP digital meters here, shipping shortly or enroute as we speak. (I also partly blame Enigma-man and his panaplex postings for this!) Brown Santa dropped off a Data Precision 3500 the other day (after opening it and extracting a pair of loose star washers and nuts that were rattling around because someone along the way stole the rear feet I fired it up and it appears to be functional. Mmmm, panaplex!); a Data Precision 134 and a United Systems 252-1 should be on their way shortly and a Triplett 8035 (individual VFD tubes) may show up tomorrow.Nope, I have no problems, I can quit any time. No worries.-Pat

author: Cubdriver
author_rank: Unknown
timestamp: August 11, 2016, 06:02:04 am
content: Quote from: bitseeker on August 11, 2016, 05:55:29 amYep!-Pat

author: bitseeker
author_rank: Super Contributor
timestamp: August 11, 2016, 06:04:10 am
content: Quote from: Cubdriver on August 11, 2016, 06:00:23 amYeah, those Panaplex displays. Gonna get me in trouble. I don't dare do a search now. Must...resist...

author: Cubdriver
author_rank: Unknown
timestamp: August 11, 2016, 08:28:49 am
content: Quote from: bitseeker on August 11, 2016, 06:04:10 amQuick and dirty iPhone pics.Meter front panel:The HP supply feeding it (including a bit of parallax error):Looking into the open top of the meter:And finally a closer view of the display:Gaze into the pretty digits... You're getting sleepy... ..sleepy... ..now, when I snap my fingers, you will go to eBuy and search for old digital voltmeters that you really don't need... <SNAP>Yeah, I know, I'm awful, aren't I?-Pat

author: Enigma-man
author_rank: Regular Contributor
timestamp: August 11, 2016, 02:53:08 pm
content: @Cubdriver:Yes, HP used standard TTL and their own chips with different pinouts. I'm sure you and bitseeker should be able to come up with any HP IC to get them upand running . The piece of equipment that has RTL logic is the Eldorado 1820A. I have a few dozen RTL's in DIP packages, but none are counter or decoders.My 5221A has the 74XX and HP TTL mix. Sphere has a partial TTL cross reference and there are others out there that I have come across.You partly blame me for your current addiction for Panaplex display equipment ? Get serious. Gimme a break.I take full responsibility. Why do you think I posted those pix ? Planting the seed... Gettin' ya hooked...Disclaimer:As you search for more Panaplex gear you will be assimilated and all your beloved HP Nixie equipment will be taken to my location in Canada. Resistance is futile...

author: bitseeker
author_rank: Super Contributor
timestamp: August 11, 2016, 09:10:33 pm
content: Dual hypnotic suggestion. I'm doomed!

author: Cubdriver
author_rank: Unknown
timestamp: August 11, 2016, 10:14:49 pm
content: Quote from: bitseeker on August 11, 2016, 09:10:33 pmOpen your wallet. Feel the burn. Embrace it. Become one with it.-Pat

author: Cubdriver
author_rank: Unknown
timestamp: August 11, 2016, 10:20:44 pm
content: Oh, and E-Man - the panaplex stuff will AUGMENT, notreplacethe nixie gear! My beloved HP anchors will not be needing passports or Canadian visas any time soon if I have anything to say about it!Resistance is voltage over current!-Pat

author: guido
author_rank: Regular Contributor
timestamp: August 11, 2016, 11:16:23 pm
content: I have two of those (see page 4). I see you have the original caps (Illinois brand). I had to replace them as they leaked, a few badly. No wonder if you put them next to the cooling fins.

author: Cubdriver
author_rank: Unknown
timestamp: August 12, 2016, 01:05:41 am
content: Quote from: guido on August 11, 2016, 11:16:23 pmAhh - that means that yours were probably the first ones I saw. I have another bought a while ago (shortly after your post on P. 4) that has a bad display driver chip. I got a replacement chip, but never got to replacing it. Thanks for the tip regarding the filter caps. Right next to what I'm guessing is the toasty voltage regulator pass transistor wasn't exactly the ideal spot for them, was it? The ones in this one appear to be in good shape for the moment, but I'll put getting some 105*C spares for them on my list of things to do.I think at this point I need to get a semi trailer load of round tuits.-Pat

author: Martin.M
author_rank: Frequent Contributor
timestamp: August 12, 2016, 04:23:54 pm
content: a grandpa of nixiethe 3 tubes count self and display that directlyhttp://www.wellenkino.de/fer/fer-1.AVI

author: Gyro
author_rank: Super Contributor
timestamp: August 12, 2016, 05:31:07 pm
content: When you look at the internal structure diagrams of those tubes the operation is really clever. Real ingenuity!

author: Cubdriver
author_rank: Unknown
timestamp: August 12, 2016, 08:20:25 pm
content: Very nice as always, Martin!-Pat

author: Enigma-man
author_rank: Regular Contributor
timestamp: August 13, 2016, 03:25:11 am
content: I saw some pictures of the BN4721 at radiomuseum.org.That one is pretty old with nine vacuum tubes in it.Good to that it survived.

author: Martin.M
author_rank: Frequent Contributor
timestamp: August 13, 2016, 02:10:41 pm
content: FER have including the gas stabilizer 11 tubes,there are 3 pcs E1T counting tubes, a 150-OB2, the input amplifier is a EF800, and 6 pcs E90CC.in rmorg are 2 FER registered, the one is from my friend Harald, and the second is this one. They are very rare today.I think they was in use to do long time countings from geiger mueller tubes in nuclear plants (radiation related to a longer time).Also there is a input for a light sensitivity sensor, for shure they mean a tube in that time, I will build one, 90 CG or like thatgreetingsMartin

author: Cyberdragon
author_rank: Super Contributor
timestamp: August 15, 2016, 08:39:16 pm
content: AC/DC Voltmeter only. Other functions not included. IC A/D converter, Diode-transistor logic controller. Open-air zener reference (still needs warm-up time).

author: bitseeker
author_rank: Super Contributor
timestamp: September 08, 2016, 01:43:05 am
content: Quote from: Cubdriver on August 11, 2016, 06:02:04 amSo, Pat, did you receive your 5216? How's it looking?

author: Cubdriver
author_rank: Unknown
timestamp: September 08, 2016, 03:31:50 am
content: Quote from: bitseeker on September 08, 2016, 01:43:05 amYes, it arrived a few weeks ago. I haven't had a chance to dig into it yet, but popped off a few pictures tonight goofing around with it. It powers up, and the tubes light, but no counting. It will take some digging; hopefully in the not too distant future. I ordered the shock mounts I need for the stepping relays in the Electro Instruments DVM that presently occupies the bench; I'd like to at least get those mounted again before doing anything else.HP 5216A Electronic Counter:And lastly what it actually looks like from a normal perspective:A few more with the fisheye are at:https://pmanning.smugmug.com/Electronics/HP-5216A-Electronic-Counter-Pat

author: bitseeker
author_rank: Super Contributor
timestamp: September 08, 2016, 04:48:06 am
content: Yeah, no rush on diving into it. Was just curious if it had arrived and what its present state of being was. Looks good overall and all the tubes still light up. If all else fails, that's enough to make it an operational nixie counter even if the circuitry has to be replaced.

author: VK5RC
author_rank: Unknown
timestamp: September 08, 2016, 11:41:39 am
content: Looks lovely, ++++.

author: TheSteve
author_rank: Unknown
timestamp: September 21, 2016, 05:05:11 am
content: HP 5340A 10Hz-18GHz frequency counter.

author: richfiles
author_rank: Regular Contributor
timestamp: September 21, 2016, 05:33:26 am
content: Alright... You win this round of awesomeness... Man, that is a beautiful beast!18 GHz feels like it must been justscreamin'back in the era of nixie tubes!Geez, is that mostly RF stuff, or were there applications I'm not even aware of?

author: TheSteve
author_rank: Unknown
timestamp: September 21, 2016, 05:40:12 am
content: Quote from: richfiles on September 21, 2016, 05:33:26 amNot sure how many industries would have needed an 18 GHz counter back when mine was made(1977). It must have been for RF use - I am thinking maybe satellite. The highest frequency I can generate is 8.4 GHz, now I need a signal gen that can go higher just to play with the counter. The inside is glorious - all gold, all the time, a total work of art.

author: bitseeker
author_rank: Super Contributor
timestamp: September 21, 2016, 09:48:16 pm
content: Steve, I was hoping you were going to post that here. It sure is a beauty and still plenty fast almost 40 years later.

author: TheSteve
author_rank: Unknown
timestamp: September 21, 2016, 09:53:02 pm
content: Quote from: bitseeker on September 21, 2016, 09:48:16 pmBuying it had an added bonus - my wife thinks it is beautiful and approves of further "vintage" Nixie purchases.And here is a picture of my Keithley 160 with red nixies

author: richfiles
author_rank: Regular Contributor
timestamp: September 21, 2016, 11:41:07 pm
content: Quote from: TheSteve on September 21, 2016, 09:53:02 pmThis man has found theholy grail.We all know that he has chosen wisely!I'm not worthy

author: bitseeker
author_rank: Super Contributor
timestamp: September 22, 2016, 03:08:46 am
content: Quote from: TheSteve on September 21, 2016, 09:53:02 pm

author: Cubdriver
author_rank: Unknown
timestamp: September 22, 2016, 03:40:57 am
content: Quote from: TheSteve on September 21, 2016, 09:53:02 pm. Sweet!! You definitely have a keeper! A perusal of this thread should certainly give you some ideas and inspiration with regard to additional acquisitions! Lord knows it and the old HP catalogs have conspired to cause my credit card a good bit of pain... Oh, and panaplex displays are pretty cool, too.(BTW, does she have a sister?)-Pat

author: TheSteve
author_rank: Unknown
timestamp: September 22, 2016, 06:25:17 am
content: Quote from: Cubdriver on September 22, 2016, 03:40:57 amHah - she does have a sister, who is already marriedNot a great loss though - she likely wouldn't approve of such toys. My wife went to Uni to be an EE and then got her amateur radio license to impress me. Then she lost interest in electronics for the most part and went into marketing and category management. She still appreciates "nice" stuff though so it's all good.All of my test gear/toys are in ManLab(tm) but she has suggested something nixie based would look nice in the living room - a clock perhaps with a correct vintage look. So I am on the hunt for the perfect piece but suspect I'll need to build something custom. There is already a vintage Motorola portable tube based radio up there. Hmm, I am a huge Motorola fan, wonder if they made anything with a nixie in it.

author: TheSteve
author_rank: Unknown
timestamp: September 27, 2016, 07:44:16 pm
content: Someone needs to buy this and show it off(fix it too of course).http://www.ebay.com/itm/201677894456

author: Cubdriver
author_rank: Unknown
timestamp: September 27, 2016, 07:56:07 pm
content: Quote from: TheSteve on September 27, 2016, 07:44:16 pmI already have one of those in the queue. I need to figure out a voltage reference substitute for it, among other things, as it used a mercury cell that is long dead and has been unavailable for many moons now. Also need to figure out the connections - it originally used remote BNC boxes that plugged into oddball connectors on the front panel.-Pat

author: bitseeker
author_rank: Super Contributor
timestamp: September 27, 2016, 11:09:41 pm
content: Quote from: Cubdriver on September 27, 2016, 07:56:07 pmIf it's got Nixies, I'd give a high probability that you've got one.It's interesting that they put the knobs in the opposite order of the displayed digits, unlike other voltage standards.

author: VK5RC
author_rank: Unknown
timestamp: September 28, 2016, 10:12:57 am
content: Notice how the guy only posts to USA, if he did post to Aust it would probably kill ht deal .

author: Cubdriver
author_rank: Unknown
timestamp: September 28, 2016, 03:22:15 pm
content: I shudder to think what shipping to Australia would costit's about 17x18x7" and weighs nearly 50 lbs,beforeyou put it in a box! That'd be a big'un to post internationally.-Pat

author: VK5RC
author_rank: Unknown
timestamp: September 29, 2016, 07:30:48 am
content: If I recall my 5245L cost about 80USD shipping, some guys will charge as much as 200USD for 10kg large type test equipment box. The only compensation ia that The price you can get for second hand test gear here is raised by about that much anyway.As my Tek 545 is coming to a close, I bought another "Unique Fixer-Up" nixie opportunity, a 3440A, it comes with the 3443 high gain plug in, from flea bay so it will be a while!

author: Cubdriver
author_rank: Unknown
timestamp: September 29, 2016, 08:18:45 am
content: A fine piece of kit!. If I recall correctly, the 3440A was the first piece of gear I restuffed a filter cap on.-Pat

author: BillyD
author_rank: Regular Contributor
timestamp: September 29, 2016, 08:56:27 pm
content: I've mentioned this guy previously on this thread, he has just put up a full length video on the making of a nixie tube.Again extremely impressive craftmanship - but don't watch if you're not of a patient disposition!

author: Johnny10
author_rank: Frequent Contributor
timestamp: October 03, 2016, 12:49:36 pm
content: My new HP5340A 1973 Option 001Not fully functioning but I can get to approx. 320Mhz

author: bitseeker
author_rank: Super Contributor
timestamp: October 03, 2016, 07:38:32 pm
content: That's a nice one, Johnny. Hopefully, it'll be pretty straightforward to bring it back to fully working condition.All,There's an HP 5221A counter on eBay.http://www.ebay.com/itm/201679287849There are also a couple of HP 3430A voltmeters.http://www.ebay.com/itm/172360688160http://www.ebay.com/itm/331962002701

author: Cubdriver
author_rank: Unknown
timestamp: October 03, 2016, 10:58:08 pm
content: The voltmeters are tempting, but still a bit too much $$. Nearly $40 to ship the one is a bit much - they're not THAT heavy or difficult to pack.-Pat

author: Johnny10
author_rank: Frequent Contributor
timestamp: October 03, 2016, 11:23:51 pm
content: The blanking of the second digit on 5221 and no decimal.Makes me wonder about circuitry.

author: bitseeker
author_rank: Super Contributor
timestamp: October 03, 2016, 11:34:40 pm
content: I concur, but figured I'd post 'em since I ran across them. One could try messaging the seller. That's worked for me a couple of times.

author: Johnny10
author_rank: Frequent Contributor
timestamp: October 03, 2016, 11:48:35 pm
content: Still 75 dollars for a parts machine.How much are those nixies really worth??I made two offers.

author: bitseeker
author_rank: Super Contributor
timestamp: October 04, 2016, 12:18:01 am
content: When it's too much, it's too much. Can't save them all.

author: bitseeker
author_rank: Super Contributor
timestamp: November 01, 2016, 10:13:43 pm
content: Here's another one that went for big money, in auction format no less:http://www.ebay.com/itm/381826570384I like the form factor of the 5321B, but $69 + shipping for one in unknown functional condition and not even including the sixth digit (from what I could tell), has me

author: VK5RC
author_rank: Unknown
timestamp: December 21, 2016, 04:08:12 am
content: OK, its not really a Nixie but pretty close. And Tubes! 22 I read somewhere. Original manual on the way as well.

author: Cubdriver
author_rank: Unknown
timestamp: December 21, 2016, 05:26:15 am
content: You snagged that one, Rob?!?Congrats!! That's a cool old beast. I now have a pretty basket-case looking 522B on its way to me.I look forward to seeing pics of your 521!-Pat

author: VK5RC
author_rank: Unknown
timestamp: December 21, 2016, 09:37:37 am
content: Hi Pat, I was happy to get this 521, she looks in good condition. Well done re the 522! My wife thought they looked quaint - I am working on her!Regards Rob

author: bitseeker
author_rank: Super Contributor
timestamp: December 21, 2016, 07:54:32 pm
content: Quote from: Cubdriver on December 21, 2016, 05:26:15 amCongrats, Rob. I, too, look forward to seeing more of the 521.

author: Enigma-man
author_rank: Regular Contributor
timestamp: December 30, 2016, 06:16:49 pm
content: Long time no see.Today's show and tell is a General Radio Model 1192-B six digit frequency counter. The specs say it will measure up to 32MHz, but this one topped out at 60MHz.The front panel shows 50MHz max. The manual is for the first version 1192 model from 1969. The parts and layout are identical. Perhaps hand picked 7490's were used to make the claimof 50Mhz. Not bad for a forty-four year old with 7400 series chips. The way you see it is the way I got it. My buddy was hunting for something and found this in a sealed plastic bag.He said, "Here, Den... Take this frequency counter..." After much arm twisting, kicking, screaming and fitted with a cast due to the relentless arm twisting, I gave in.Almost as pristene as the HP counter I showed you a few months back. It was repaired somewhere along the line by someone who knew what he or she was doing. NoPC board damage and solder flux cleaned up. A true sign of someone who takes care in what they do. Anyway, it powered up okay and zeroed out. There is a 100KHz testbutton on the front panel. It read exactly that when on the 10 sec gate time. One picture shows the display on the 1 sec gate time.Originally it had six digits. After opening it up, I saw standard 7490 counters and other TTL devices. I had a display driver and storage IC, but not the miniature Nixie that wereinside. I compared a standard Burroughs Nixie to the mini one and found the two to be identical except for the glass envelope. I unsoldered the socket for digit seven and seatedthe one I had on hand. You cannot tell the difference. In future if one of the mini ones craps out, a standard one can be subbed once the socket is removed. Maybe not 100% originalbut what would one do if you could not find a mini one ? Eventually all Nixies will die...The other minor repair was the filter cap for the 5 Volt line. It is mounted with screws and you cannot slap anything in there. It had to be the right height. Shorter is okay, taller is not.I had only one which fit the bill. 10,000uF at 25 volts. The original was a 15 Volt, but so what ?The other mod was removing underrated diodes that had started to burn the pc board. I put in a 5 Amp bridge and used the chassis as a heat sink.The time base is a bit odd. A 5MHz crystal is used along with a frequency doubler, then divided down to get your various timebase values. It would be very easyto put in a 10.0000 MHz oscillator module along with a 74LS390 dual decade counter if and when the timebase fails.

author: Enigma-man
author_rank: Regular Contributor
timestamp: December 30, 2016, 06:17:58 pm
content: Not exactly a Nixie device, but still a cold cathode device are the Dekatrons (GC10B/S) 4KHz maximum frequency rate decade counter tubes. These are the grandfathersof display devices. I downloaded the Ericsson design manual from Deiter's site. The extensive manual shows how to make actual frequency dividers. I hope to make a frequencycounter out of the tubes. Some have blown away zero cathodes from displaying zero all the time, but those can be used as reverse Dekatron spinners spinning counter clockwise.Aussies will enjoy this because water going down the drain goes in reverse compared to us Northern Hemisphere people.The tubes need 450 Volts DC. Hooking up to a computer such as an Arduino, Raspberry or any other computer is a piece of cake. All timing is done in software and no big deal.My counter will use discrete components and interfaced by optoelectric means. There is a section in the manual that touched on this using photodiodes/transistors. Six or eight pinoptoisolators are everywhere and should not be a problem. 4KHz is not high frequency, but a hybrid could use the four tubes on the left displaying the KhZ or MHz value with the othertubes used as indicators driven by high speed TTL or ECL.Lastly there are two Japanese edge lit displays. There are ten etched glass wafers inside; each driven by a 48 Volt miniature bulb. It is possible to use high intensity LEDs instead ofthe bulbs to make it easier to interface to logic chips/drivers but would require one to make a pc board instead of what is there now. Not a big deal for the determined.I must say that a blue led display looks really cool. Any colour LED could be used. High intensity white and blue are what I have on hand. The white looks good too.I suppose mulicoloured LEDs could be used. An ever changing display with all the colours of the rainbow... Hmmmm....The two digits I have were used in some sort of time measurement device, probably a clock or time event counter. The left digit is wired from zero to five while the other is fromzero to nine. All of the bulbs work but interfacing 48V to CMOS or TTL requires more parts either as discrete transistors or a few high voltage driver chips. Also, miniature 48V bulbsare not common any longer.Dang typo errors... Never see 'em in the preview before posting. Always after when everybody can see the typos...

author: bitseeker
author_rank: Super Contributor
timestamp: December 30, 2016, 06:31:09 pm
content: Welcome back, Enigma-man! That Gen Rad counter looks to be a great condition. Nice power supply upgrade and Nixie mod. For the power cord, it appears that a regular extension cord would work. It's good that the connector isn't recessed like I've seen with some full-width rack-mounted equipment of the era.Looking forward to seeing your Dekatron-based counter project. RGB LEDs for those edge lit glass displays would be interesting as an additional output channel. As the count goes toward a particular limit, the color could change accordingly, for example.

author: Enigma-man
author_rank: Regular Contributor
timestamp: December 30, 2016, 06:46:01 pm
content: Yes, a three wire extension cord could work as well. I used the adapter because it never got used for anything and was lounging around in a box with other cables doing nothing.Also, the fit from the adapter is very tight and you have to work at it to get it to fit properly. I didn't want to crack the connector by removing the adapter. It's easier to unplug thepower cable from the adapter when you have to go inside.

author: bitseeker
author_rank: Super Contributor
timestamp: December 30, 2016, 06:52:53 pm
content: Yeah, I remember those adapters for attaching a CRT monitor with a regular plug to a PC power supply. That was a looong time ago.Hmm, I may still have an amber monitor with the correct plug somewhere.

author: ben_r_
author_rank: Frequent Contributor
timestamp: January 05, 2017, 11:14:25 pm
content: Ha! Man there is some cool Nixie tube gear out there! I had no idea there was so much!

author: Cubdriver
author_rank: Unknown
timestamp: January 06, 2017, 02:56:17 am
content: Quote from: ben_r_ on January 05, 2017, 11:14:25 pmOh yeah, there's plenty of it out there! Trust me, do NOT look through old HP catalogs.-Pat

author: VK5RC
author_rank: Unknown
timestamp: January 06, 2017, 07:17:56 am
content: Just a bit of a teaser, like a low cut dress, see enough to raise interest!My 521C , OK not a real Nixie but of similar vintage/design. A couple of gassy tubes on quick inspection - one rectifier . I will give it it's own post a bit later.

author: TheSteve
author_rank: Unknown
timestamp: February 16, 2017, 07:02:11 am
content: The Nixie's in the HP 5340A are the sweetest ones I have come across. I'd like to build a clock using them but can't possibly sacrifice my beautiful working 5340A. Does any other HP gear use same really small nixies? I suspect I'll likely be shopping my favorite auction site for another 5340A to rob the nixies from...

author: Cubdriver
author_rank: Unknown
timestamp: February 16, 2017, 07:45:16 am
content: Quote from: TheSteve on February 16, 2017, 07:02:11 amThat there kinda talk might earn ya a beatin' in these here parts...Off the top of my head I don't know what else uses them, though I'm fairly certain other things do. I think the 5360A computing counter might use the same ones. I'm not suggesting that you kill one of those, either, mind you! I'll try to find the part number of the tube, perhaps you could find some spares on the credit card killing auction site...-Pat

author: Cubdriver
author_rank: Unknown
timestamp: February 16, 2017, 08:08:33 am
content: Rat Shack used to sell a small nixie (think it was a Burroughs part) - RS part number 276-048. They occasionally show up on the auction site. That might be something to look for. Smaller than those in the 5340A, but still nice little display tubes.What makes my want to cry is that when they were new they were $2.50 each. Wish I'd bought every one I saw!-Pat

author: TheSteve
author_rank: Unknown
timestamp: February 16, 2017, 07:11:16 pm
content: Quote from: Cubdriver on February 16, 2017, 07:45:16 amI hear ya! I don't think I'd sacrifice a fully working unit but there are lots out there with some dead parts that are near impossible to replace. And then I'd have a parts unit to help others.

author: bitseeker
author_rank: Super Contributor
timestamp: February 16, 2017, 07:12:03 pm
content: Quote from: TheSteve on February 16, 2017, 07:02:11 amYeah, don't sacrifice your 5340. Sell it to me before you do that. Meanwhile, if you haven't already, check out this site for a variety of Nixies.http://www.sphere.bc.ca/test/nixies.html

author: edpalmer42
author_rank: Super Contributor
timestamp: February 16, 2017, 08:14:41 pm
content: Quote from: VK5RC on January 06, 2017, 07:17:56 amI had a similar unit. It was a Beckman/Berkley 7360A EPUT (Event per Unit Time) meter that was spec'ed to go up to 2 MHz. It worked, but only made it to about 1.5 MHz due to a tube substitution on the LSD (Least Significant Digit). Four tubes per digit, seven digits. The digit modules are all socketed. Remove the screw from the front panel and the digit unplugs. The LSD unit and maybe the Most Significant were different, but the rest were identical.I found a recent message thread, with pictures, here:http://www.antiqueradios.com/forums/viewtopic.php?f=8&t=306292Unfortunately, it was just too big (19" rackmount, 10.25" high x 16" deep, 65 pounds) and I just didn't have the space for it, so it had to go.

author: worsthorse
author_rank: Super Contributor
timestamp: February 16, 2017, 08:29:30 pm
content: I just picked up a Monsanto 100C nixie tube counter which appears to be working, though I haven't tested it yet. Will post photos later today. Wondering if anyone else has one of these... I am looking for a manual or spec sheet and would like to avoid spending 30 bucks on ebay to get one. thanks - bill

author: Cubdriver
author_rank: Unknown
timestamp: February 17, 2017, 12:56:37 am
content: Quote from: TheSteve on February 16, 2017, 07:11:16 pmVery true. There is a custom IC in the signal path that seems inclined to crap out (I have one with that failure). I ordered what was supposedly a working replacement board about a year ago, but haven't gotten to revisit the counter to install it since then. The few times that particular IC has appeared on the 'bay, the sellers wanted as much or more for it than I paid for the counter. My fingers are crossed that the replacement board (when I finally get to it) brings things back to life.-Pat

author: VK5RC
author_rank: Unknown
timestamp: February 17, 2017, 05:08:49 am
content: A new addition - just needed a little cleaning. Works at full speed and sensitivity 12MHz 10mV input

author: bitseeker
author_rank: Super Contributor
timestamp: February 17, 2017, 05:11:39 am
content: Well, well. That certainly looks familiar. Cleaned up nicely!

author: VK5RC
author_rank: Unknown
timestamp: February 17, 2017, 05:18:44 am
content: It was the 5216 from Poland, I was outbid on the other recent 5216 - if I recall the other one was from the USA.

author: Cubdriver
author_rank: Unknown
timestamp: February 17, 2017, 06:19:40 am
content: Looks nice, Rob!I finally got mine cleaned up and working, and have been meaning to post a tear down thread but am being lazy. Perhaps I'll get my butt in gear and do it this week.More pics at:https://pmanning.smugmug.com/Electronics/HP-5216A-Electronic-Counter-Pat

author: VK5RC
author_rank: Unknown
timestamp: February 17, 2017, 06:28:43 am
content: Hi Pat, I did appreciate the fact you connected yours to the correct era of HP gear, mine unfortunately was connected to some of this modern rubbish - with silly colour displays. In my mind a REAL display is monochrome orange or red or possibly blue/green at a pinch.Yours looks in great nick, mine is missing the front foot - it has the metal part but not the plastic foot. It is times like this I think about 3D printing - if only there was a linked 3D laser scanner! If someone was able to scan one in - then we could 3D print to our hearts' content. I certainly am not up to that.The teardown/repair/clean would be interesting+++Rob

author: Cubdriver
author_rank: Unknown
timestamp: February 17, 2017, 06:33:08 am
content: And I replaced the missing tubes in the 522B (cousin to your 521) and tried firing it up the other night. It works to some extent at least, counting in manual gate mode. I haven't tried putting an actual signal into it yet as I turned it on on a whim and it's in the living room and not near a signal source. I still need to do some serious scrubbing to pretty it up, but it shows signs of life despite its age.Here's a crappy iPhone photo of it as it came, and at the smugmug link there's a short video of it counting in the timing mode. The knobs don't seem to be original, but I'm happy that the old beast lights up and seems to function.As it arrived:A few other iPhone pics, and the video are here:https://pmanning.smugmug.com/Electronics/HP-522B-Electronic-Counter-Pat

author: Cubdriver
author_rank: Unknown
timestamp: February 17, 2017, 06:47:00 am
content: The feet are an issue all to often. Either they broke off down through the years (though they are pretty tough!), or more likely were removed and tossed when instruments were rack mounted. That or people poach them and sell them separately for stupid $$. The newer all plastic ones are readily available at barely tolerable cost, but the old black ones usually used on the nixie era gear are not so easily had, and the few I see on the bay are often crazily priced. It's to the point where I'll bid at least somewhat higher for gear that still has the old black feet. The one piece type on these smaller instruments are even harder to find. Ugh!I must say that it's nice to see that both yours and mine both have their HP emblems intact. I'd love to stumble upon a box of NOS HP emblems somewhere! I don't understand why THOSE seem to go missing from so many things.-Pat

author: Johnny10
author_rank: Frequent Contributor
timestamp: February 17, 2017, 12:49:09 pm
content: I still have 4 cosmetic/mechanical issues with my 5216A.The plastic screen has a brush mark which needs to be removed. (Some sort of abrasive plastic polish or find another colored plastic sheet ?)I do not have the proper power plug. ( IEC? File out a new opening?)The aluminum frame needs to be polished. Tried running a bit of 800 grit sandpaper but still a corroded and dull.The HZ, KHZ, MHZ screened designators are distorted and missing bits of coating. The lights work fine. (Make stencil and respray?)

author: bitseeker
author_rank: Super Contributor
timestamp: February 17, 2017, 06:38:02 pm
content: Quote from: VK5RC on February 17, 2017, 05:18:44 amYep, I was watching those too. They don't come up often so it's fun to see. There was a 5221A recently, too.

author: bitseeker
author_rank: Super Contributor
timestamp: February 17, 2017, 06:40:28 pm
content: Quote from: Cubdriver on February 17, 2017, 06:19:40 amI still have to tear into mine. It'll probably be next after I wrap up the power supplies that have consumed my bench.

author: bitseeker
author_rank: Super Contributor
timestamp: February 17, 2017, 06:46:34 pm
content: Quote from: Johnny10 on February 17, 2017, 12:49:09 pmThat should just polish out if it's not deep. I'd try that before replacing.QuoteIs it the oval-shaped connector? You can get the correct cable, though they're not cheap. One of my 5216 has it, too. The other is the more modern IEC.This one is a bit more rectangular than I've seen before, but might work:http://www.ebay.com/itm/142280298717These are "normal" looking:http://www.ebay.com/itm/111978547722http://www.ebay.com/itm/122312916577http://www.ebay.com/itm/371848014001

author: Cubdriver
author_rank: Unknown
timestamp: February 17, 2017, 07:18:36 pm
content: Johnny -As far as the filter for the display goes, I'd first try plastic polish - Novus is one kind, and a plastic headlight restoration kit from an auto parts store might be another option. I haven't found a readily available source for amber tinted Plexiglas or Lexan that's thin enough to replace it (though I also haven't really looked beyond McMaster-Carr and a cursory Amazon search - a plastic supplier would likely have something though minimum quantities may be an issue there). I think I recently read in an HP blurb somewhere that at least some of those filters are polarized, too, but haven't checked that out so don't know for certain. It doesn't appear to me to be dark enough to be polarized, so I'm not sure I believe that.For the scuffed side castings, when I did my 3460B, I took them off completely and wet sanded the scuffs out in the kitchen sink. Do them one at a time, and the opposite one that's still in place will keep the instrument mostly intact. I likely started with 180 or 200 grit, then went to 400, 600 and finally 800 or 1200. The 5216A castings would be much easier to do - they'd fit in the sink! I wrapped the sandpaper around a small whetstone to keep it flat and prevent rounding off the sharp edges where the side and outer flats meet. The 3460 ones were too long and a PITA to do without getting water splashed everywhere. I think the results were worth the effort, though.Before wet sanding:The same area after wet sanding:-Pat

author: Cubdriver
author_rank: Unknown
timestamp: February 17, 2017, 07:31:30 pm
content: The oval AC Mains connector HP used is a PH163. The HP ones are 'odd' in that the line and neutral conductors are swapped from other, similar versions of that connector.http://www.cs.ubc.ca/~hilpert/e/powerConn/index.htmlHas some info on them.I try to keep an eye out for the cords, and grab them when I get a chance as I have a ton of gear that uses that connector. Unfortunately they are few and far between, or $$$. Replacing the mains input with an IEC320 connector is always an option if surgery on the chassis doesn't bother you. I've occasionally found cords with Euro CEE 7/7 plugs on them; if you get the opportunity grab those and cut off & replace the original plug with a NEMA 5-15P and you're good to go.-Pat

author: Johnny10
author_rank: Frequent Contributor
timestamp: February 17, 2017, 07:58:03 pm
content: Appreciate all the advice !

author: VK5RC
author_rank: Unknown
timestamp: March 12, 2017, 07:54:14 am
content: Hi guys, I have finally got around to finishing testing all the 521Cs tubes, well the ones I could anyway. I ended up replacing 5 tubes eventually, quite a large number really - most of the failing tubes had gone gassy. Main caps OK, fan works, transformer ok.I used my uTracer- (after I broke it, then repaired that as well!)This is one of HP not good designs I think. The frequency divider circuit styled after a phantastron, to me , looks like a charge pump, and with differences in loading of each divide by ten circuit (whether it is in 1/10, 1 or 10sec count mode) results in different divisors (9,10 or 11) , you can adjust each stage to divide correctly. The different range selections obviously load the divisors inconsistently, so if you count in the 'wrong' range the answer can be out by 10% or so. I am sure when it came out of the factory all the caps were in value etc and it didn't do this but now it does. I think I am going to leave it. Otherwise it works well.

author: bitseeker
author_rank: Super Contributor
timestamp: March 13, 2017, 05:25:07 am
content: Congrats on getting the 521 running, Rob. That must be fun to watch with an FM signal. A stable CW would be boring.

author: Cubdriver
author_rank: Unknown
timestamp: March 13, 2017, 05:43:21 am
content: Mmmmm. Very pretty glow!Nice to hear that it's up and running, at least most of the way. Very cool old piece of gear!-Pat

author: TheSteve
author_rank: Unknown
timestamp: March 24, 2017, 09:02:19 pm
content: Pulled the trigger on another HP 5340A - this one was sold for parts, the >250 MHz input is dead. If it is an easy fix I'll preserve it, if not the nixie's get a new home.btw the same seller has a Heathkit IB-1103 frequency counter that has 8 nixie's in it that looks pretty interesting. A low best offer might just take it.http://www.ebay.com/itm/232282084251

author: VK5RC
author_rank: Unknown
timestamp: March 25, 2017, 08:56:23 am
content: OK not Nixie gear but often related to it.PINOUT of LL14847I am in the process of making some US LL14847 cables into AUS cables - I am now confused - two premade cables have different pinouts!In my 'scrap piece of paper' , God knows where I got the pinouts from, to remind me of mains cables (Also US, AUS, IEC) etcIn the below photo theTOP socket is NeutralCENTRE GroundBOTTOM is Active/LineIs this correct???Thanks guysRobert

author: Cubdriver
author_rank: Unknown
timestamp: March 25, 2017, 03:22:08 pm
content: Quote from: VK5RC on March 25, 2017, 08:56:23 amRob -That is correct - HP used the 'reverse polarity' version. As you have it drawn and labeled is the proper wiring for old HP gear. I posted a link to a website showing this a while back, but I'll be damned if I can find it now. Ugh! I did just confirm by measuring one of my PH 163 HP type power cords just now, though.-Pat

author: VK5RC
author_rank: Unknown
timestamp: March 25, 2017, 10:49:14 pm
content: Thanks Pat, I recalled vaguely ( as most of my recollections are now!) you commenting about it, but I couldn't find any links myself.I suppose the good thing is most HP gear, both mains leads are isolated.ThanksRobert

author: bitseeker
author_rank: Super Contributor
timestamp: March 26, 2017, 02:06:53 am
content: I also recall that peculiarity and have seen a page online about some devices using reversed polarity (not just HP's). Alas, I am unable to re-find the info.

author: Cubdriver
author_rank: Unknown
timestamp: March 26, 2017, 04:10:06 am
content: Well, I just found the page link I was referring to. Reply 230 above. And i now know why I couldn't find it earlier today - the page is apparently gone - I get a 404 error now.Oh well, at least we know what the connector is (a PH 163), and that the polarity is reversed on old HP stuff, and at least a few of us have linecords that can be checked to confirm the proper pinout.-Pat

author: bitseeker
author_rank: Super Contributor
timestamp: March 26, 2017, 04:48:19 am
content: Here's a copy on archive.org:https://web.archive.org/web/20160802081036/http://www.cs.ubc.ca/~hilpert/e/powerConn/index.htmlAnd just in case it disappears, a quote of the relevant part about the 163:QuoteAttached is a photo of the pinout from that site.

author: Cubdriver
author_rank: Unknown
timestamp: March 26, 2017, 05:23:26 am
content: Nice find, bitseeker. Good call on 'archiving' it here! That's the bad thing about the interwebs - good info can up and vanish without warning.-Pat

author: VK5RC
author_rank: Unknown
timestamp: March 26, 2017, 10:25:42 am
content: Thanks pat and bitseeker- I feel justified in my confusion - fortunately all my type 163 connectors are all HP .I will put a link in the Repair Post.Robert

author: TheSteve
author_rank: Unknown
timestamp: March 29, 2017, 06:15:32 am
content: They are beautiful!Two screws and the entire display module unplugs.

author: Johnny10
author_rank: Frequent Contributor
timestamp: March 29, 2017, 07:22:47 am
content: TheSteve,You are making me jealous.

author: james_s
author_rank: Super Contributor
timestamp: April 01, 2017, 09:25:23 pm
content: I picked up this Keithley 160 from ebay about 15 years ago, I don't remember how much I paid but it wasn't very much. I think I bought it for the tubes but then realized it was in nice condition and works. Now I got a calibration standard so I pulled out the meter to try it out, after warming up for a bit it's pretty much dead on which is impressive given it probably hasn't been calibrated in at least 30 years.

author: bitseeker
author_rank: Super Contributor
timestamp: April 01, 2017, 11:08:07 pm
content: That's a beauty, James. I'm glad you didn't strip it for the tchoobs.

author: BU508A
author_rank: Super Contributor
timestamp: April 04, 2017, 09:23:50 am
content: There is a really nice meter on ebay with five Z566M Nixies and one Z567M:http://www.ebay.de/itm/252841505068Pity, seller is shipping the meter only to Germany.But the pictures are great.

author: bitseeker
author_rank: Super Contributor
timestamp: April 04, 2017, 07:03:27 pm
content: That is really cool. Never saw one of those before. It's interesting that the tubes themselves are red, too. Attaching some photos here for posterity.

author: james_s
author_rank: Super Contributor
timestamp: April 04, 2017, 07:09:27 pm
content: I have some red coated Nixie tubes. The coating provides a built in filter and contrast boost without requiring a separate filter.

author: rsjsouza
author_rank: Super Contributor
timestamp: April 04, 2017, 08:13:05 pm
content: A similar piece of gear of the OP. Casio AS-A:

author: VK5RC
author_rank: Unknown
timestamp: April 05, 2017, 12:54:38 pm
content: OK its not a true Nixie but a 'Dot LED' comes close - and will warm Cubdriver's heart.My birthday is coming up soon - my wife let me choose -an 8662A - some serious HP iron - funky display and good phase noise. (and a good room heater as well - 450VA)Coming from the USA soon I hope!

author: AF6LJ
author_rank: Unknown
timestamp: April 05, 2017, 01:19:18 pm
content: Those are nice generators, and a fine example of truly good HP Iron.

author: bitseeker
author_rank: Super Contributor
timestamp: April 05, 2017, 06:10:38 pm
content: Yeah, has the nifty lit buttons too.

author: Cubdriver
author_rank: Unknown
timestamp: April 05, 2017, 06:28:01 pm
content: Quote from: VK5RC on April 05, 2017, 12:54:38 pmBeauteous!(Though I shudder to think what shipping on that weighty beast must be)(And it sounds like you have a pretty awesome wife, too!)-Pat

author: AF6LJ
author_rank: Unknown
timestamp: April 05, 2017, 09:48:24 pm
content: Quote from: Cubdriver on April 05, 2017, 06:28:01 pmYou don't want to know.It's not often you see a solid state signal generator draw almost half a KVA...

author: VK5RC
author_rank: Unknown
timestamp: April 06, 2017, 02:51:37 am
content: Thanks, I hope 'she' (like all good battle ships) arrives well, I can't figure out eBay's shipping $, it wasn't too bad. About USD $120 but can at times be triple that!Re my wife, very lucky guy I am.Rob.

author: AF6LJ
author_rank: Unknown
timestamp: April 06, 2017, 02:54:20 am
content: Quote from: VK5RC on April 06, 2017, 02:51:37 amNot too bad.

author: Cubdriver
author_rank: Unknown
timestamp: April 06, 2017, 03:23:25 am
content: Quote from: VK5RC on April 06, 2017, 02:51:37 amWow, that's a really good rate! It set me back $75 to ship that Fluke calibrator home from CA in February; I'd imagine that they're similar in size and weight - boxed up the calibrator tipped the scales at 77 lbs and was in a 30 x 20 x 14" carton (It's loooooooooooooong!). I'd have expected similarly sized shipment to down under to be at least twice that.Assuming she was packed reasonably, she should arrive safely given that HP gear of that era is built like a battleship! Congrats on your new 'toy'.-Pat

author: VK5RC
author_rank: Unknown
timestamp: April 06, 2017, 10:33:54 am
content: Pat, Sue, I was pretty happy with that postal rate, I don't understand eBay's postal charging system, often for the typical HP box from USA to AUS is around USD$ 230. Can still take 3 weeks. The worst example I had was a spare part HP strap handle - the ones about 60cm long on the sides - it went from USA to Oslo! As it was not able to be delivered in Australia in Oslo (fancy that!) it was returned to USA - the eBay seller chased it down - great guy- then resent it.Rob

author: bitseeker
author_rank: Super Contributor
timestamp: April 25, 2017, 09:51:25 pm
content: Keithley 190 teardown thread:https://www.eevblog.com/forum/testgear/keithley-190-5-12-digit-nixie-tube-multimeter/

author: idpromnut
author_rank: Unknown
timestamp: May 04, 2017, 06:29:07 pm
content: I will be part of this delightful group soon! Until then, have a picture of a nice clock (the electronics are a kit, the case was made by me):Write up (if one cares to read some rambling with pictures):http://clog.unrecoverable.org:8060/2013/01/nixie-clock-case/

author: Gyro
author_rank: Super Contributor
timestamp: May 04, 2017, 06:42:43 pm
content: Nice case construction!All you need to do now is get rid thoseawfulblue LEDs!

author: bitseeker
author_rank: Super Contributor
timestamp: May 04, 2017, 06:44:59 pm
content: Hehe, I'm not a fan of the blue LEDs, either. If anything, I'd change them to amber ones that matched the Nixie glow.Nice case!

author: idpromnut
author_rank: Unknown
timestamp: May 04, 2017, 07:10:48 pm
content: I actually liked the contrast in color (and the LEDs were part of the kit) but I might give other colors a try. Thanks for the idea

author: mc172
author_rank: Frequent Contributor
timestamp: May 04, 2017, 08:45:00 pm
content: Why fitanyLEDs?

author: Gyro
author_rank: Super Contributor
timestamp: May 04, 2017, 08:50:42 pm
content: It looks as if the "delightful group" wish to differ with you on matters of taste.Don't take it personally though, taste is indeed a personal thing.

author: bitseeker
author_rank: Super Contributor
timestamp: May 04, 2017, 10:21:20 pm
content: Quote from: Gyro on May 04, 2017, 08:50:42 pmAbsolutely! Build it the way you like.

author: james_s
author_rank: Super Contributor
timestamp: May 05, 2017, 12:16:59 am
content: I personally am not a fan of mixing LEDs with nixie tubes but this certainly falls under the category of personal taste. Overall I'd say it's a nice clean build.

author: jnd
author_rank: Regular Contributor
timestamp: May 18, 2017, 08:38:38 pm
content: Three years ago I bought this old style Metra MT100 voltmeter, listed as non working for about $15. Today revisited the repair attempt and with some luck it is measuring again! Zero is spot on, the calibration voltage is out of adjustment range, will have to look into that. Also the input is quite unstable and the transistor stabilizing 5V rail is getting way too hot, I should check for any excess power consumption or I'm afraid it will burn up. So all in all, repair in progress

author: bitseeker
author_rank: Super Contributor
timestamp: May 18, 2017, 11:53:31 pm
content: That's coming along nicely, jnd. Keep up the good work.

author: Gyro
author_rank: Super Contributor
timestamp: May 19, 2017, 10:43:33 am
content: Nice 15mV range - always useful!

author: neo
author_rank: Super Contributor
timestamp: July 15, 2017, 03:41:59 am
content: Quote from: Enigma-man on August 10, 2016, 04:43:07 amI have a multimeter of that exact model! I was beginning to think no one else did!

author: neo
author_rank: Super Contributor
timestamp: July 15, 2017, 03:47:08 am
content: Quote from: Enigma-man on August 10, 2016, 04:43:07 amI have a multimeter exactly like that! I was beginning to think no one else did!Quote from: Enigma-man on August 10, 2016, 09:27:00 pmHEY!! I like the way it looks!

author: neo
author_rank: Super Contributor
timestamp: July 15, 2017, 04:12:40 am
content: Quote from: richfiles on September 21, 2016, 05:33:26 amI have a 5340A s well. Mine was made in '73 and it has a metal badge on it that says "Communications satellite corp. Washington DC"

author: Cubdriver
author_rank: Unknown
timestamp: July 15, 2017, 05:13:29 am
content: Quote from: neo on July 15, 2017, 04:12:40 amApparently '73 was a strong year for the breed:(I'm still waiting on an extender card that was ordered on Sunday to continue troubleshooting mine. Friggin USPS!)-Pat

author: neo
author_rank: Super Contributor
timestamp: July 15, 2017, 05:17:56 am
content: Quote from: Cubdriver on July 15, 2017, 05:13:29 amCheck the repair page if you have time, there's a pleasant surprise.

author: neo
author_rank: Super Contributor
timestamp: July 15, 2017, 06:01:43 am
content: My nixie tube equipment below. A work in progress 5340A and a fully working and well adjusted Fairchild 7050. By well adjusted i mean it agrees with my flukes 8000A which agrees with my freshly calibrated lcd multimeter.Third pic is problem with 5340A, any ideas welcomehttps://www.eevblog.com/forum/repair/frequency-counter-won't-count/125/.Forgive the darkness, this is without flash and it is not really that dark to human eyes.

author: VK5RC
author_rank: Unknown
timestamp: August 09, 2017, 09:50:29 am
content: OK its not really a Nixie but of similar heritage, I got this for a case of beer from a radio club colleague who is cleaning out and downsizing. He even had the original manuals!She is alive, and only weighs about 20kg.A new power cord, and quite bit of cleaning ahead.

author: bitseeker
author_rank: Super Contributor
timestamp: August 09, 2017, 07:51:09 pm
content: Very cool. Are the two sections significantly different age, hence the major color difference?

author: VK5RC
author_rank: Unknown
timestamp: August 10, 2017, 11:19:21 am
content: @bitseeker - I don't know if there is an age difference - one of the units its serial number plate has fallen off - I don't think they used the 1960 + the first two digits for the year of production for these subunits.It looks better in the photo than is does in reality - quite a bit of corrosion on the aluminium - I am not sure if I can do a robrenz on the dials (he glass bead blasted then filled the engraved slots with black epoxy !) I have rubbed in a bit of gun oil (I don't own a gun) but it works nicely lightening the aluminium corrosion and makes the digits stand out more.I was just glad it worked. Cleaning is the main issue now.

author: Cubdriver
author_rank: Unknown
timestamp: August 10, 2017, 03:01:58 pm
content: Rob -Any components with date codes easily accessible? My guess is that the tan faceplate one is more recent production than the grey one, but I'm not sure when the color change took place. (And for all I know, it could have been a gradual thing and both could be the same age.) Regardless, I'm glad to see it up and running!-Pat

author: AF6LJ
author_rank: Unknown
timestamp: August 10, 2017, 03:13:24 pm
content: Quote from: bitseeker on August 09, 2017, 07:51:09 pmOn that analyzer they would be.

author: Cubdriver
author_rank: Unknown
timestamp: August 10, 2017, 09:10:40 pm
content: I recently got a Fluke 8200A meter to join the 8100A and 8120A already in the stable. I haven't gotten around to opening any of them yet, but did connect them to the 5440B calibrator this afternoon for a quick wring-out on the DC scale at least. The 8200 will need some work as it's pretty close at middle voltages (around 100V), but a bit low at very low voltages and it starts going off the rails at higher inputs - about 3V high at 250, increasing to as much as ~20V high at 999V in.It's a bit grimy, as I haven't yet attempted to clean it at all, but I expect it should polish up nicely. (The atrocious looking mark on the upper right corner of the front panel appears to be sticker residue, rather than an asset tag that was removed with a cold chisel as the one on my HP 4262A LCR meter apparently was.) I did find a paper manual for it, so I'm in good shape there.Meter as received:Group photo with its siblings @ 100V in:Additional pics of the three meters being fed various voltages are at:https://pmanning.smugmug.com/Electronics/Fluke-Misc-Pat

author: neo
author_rank: Super Contributor
timestamp: August 10, 2017, 09:19:43 pm
content: Quote from: Cubdriver on August 10, 2017, 09:10:40 pmNow i want one worse!Hopefully i find an 8200A at hamfest in two weeks. If i don't i will probably come home and order it or a 8100.

author: bitseeker
author_rank: Super Contributor
timestamp: August 10, 2017, 09:29:22 pm
content: Quote from: VK5RC on August 10, 2017, 11:19:21 amYeah, his restorations are awesome -- a completely different league. I'm happy if I can get all the stickers, glue, etc. off while still preserving silk screened lettering, lines, and iconography. Accidentally wiping off silk screening is such a bummer. Older gear with engraved panels is so much better!

author: Cubdriver
author_rank: Unknown
timestamp: August 10, 2017, 09:54:30 pm
content: Quote from: bitseeker on August 10, 2017, 09:29:22 pmSounds to me like a good excuse to buy a bead blasting cabinet.And yes, engraved is much better than silkscreened. I'd say the anodized in lettering on some of the older Tek stuff is a close second.-Pat

author: bitseeker
author_rank: Super Contributor
timestamp: August 10, 2017, 10:48:35 pm
content: One of these days, I'd like to try etching an alumin(i)um or brass front panel. I already have plenty of power supplies to choose from and deep, crisp etching doesn't require much voltage.

author: Cubdriver
author_rank: Unknown
timestamp: August 10, 2017, 11:11:29 pm
content: Must resist the urge to look into etching panels....-Pat

author: bitseeker
author_rank: Super Contributor
timestamp: August 11, 2017, 12:50:22 am
content: Forget I said anything. Hrm, I guess it's too late for that. Well, maybe start a new thread for it.

author: VK5RC
author_rank: Unknown
timestamp: August 11, 2017, 10:22:28 am
content: My GAS is bad - I do have a blasting cabinetIt worked really well cleaning the side panels of my Tek 545I am a bit worried as the engraving is so fine - even with glass bead I might blast the edge of the lettering / numbers so the recognition is lost.

author: Johnny10
author_rank: Frequent Contributor
timestamp: August 14, 2017, 03:53:51 pm
content: Not sure if I posted this BLH unit before in Nixie Tube Equipment before?But what the hey!

author: bitseeker
author_rank: Super Contributor
timestamp: August 14, 2017, 06:58:46 pm
content: I don't recall seeing one. Thanks, Johnny.

author: Vince
author_rank: Super Contributor
timestamp: October 06, 2017, 09:54:13 pm
content: Hi there,Just came across this page ! I assumed EEVBlog was more about modern electronics but I am glad to see that this forum has grown so huge over the years, that the old stuff now enjoys a sufficient audience to generate many and interesting threads !Took my time and went through all 12 pages with great interest. These 7 segment nixies are incredible ! OK, it seems they were called "lumitron" or something, if I understood you correctly. Come to think of it they were very common place a few years back. I used to see them all the time at gas stations, the pumps would display fuel quantity and price on these nice displays.I also loved this Russian piece of gear on the first page IIRC, with its mat black aluminium facia, it looks superb. Makes the nixies really stand out, beautifies them. I love this black + nixie combination, wish the "western" manufacturers used it at least sometimes back then, rather than the same aluminium theme all the time.Anyway. after 15/20 years of sleep, my passion for electronics eventually woke up, 12 months ago. I started searching for gear to equip the bench. A couple a months or so ago while doing my daily search for local/French stuff, I came across a nixie counter ! First nixie piece of gear in 12 months of daily search !!! Was complete and in great nick, full featured, decent spec (20MHz 5 digits), in working order, not dirt cheap but reasonably priced, I just couldn't resist the temptation, bought it !!!It's a Schlumberger, 1971 vintage IIRC, model FM 2502. The seller was an old engineer who bought it brand new back then, hence he still had the original user manual and schematics for it ! This alone is a treasure... normally on these old French instruments you can never find the schematics, never mind a full manual !It also features a 5 digit pre-scaler as you can see on the pics.Seller was super nice, we kept exchanging e-mails. said he was clearing his lab of many of his older instruments to make room for more modern instruments... 69 year old but still very actively working in his lab ! Doing RF stuff mostly, but anyway. Said he had already sold most of his old stuff but that he still had one nixie instrument left, that I might find interesting.... indeed it was interesting, bought it in a heart beat !!! Another counter. So that's 2 nixie counters in one go !It's a Metrix DX 446A. What got me excited was the performance of the thing compared to the other counter : not 5 but 8 digits, wow, and 160MHz ! Without a prescaler ! AC coupled though, but I tested it and it starts working from as low as 120kHz.Again, fully working and with full original documentation, a gem.Obviously I have since learned, confirmed on here, about the marvelous HP 53XX series ! Sure want one of those ! The 5340 at least, with it's 20GHz input !Obviously in frog land I will never find one, so hopefully will find one in Europe somewhere, or on Ebay US if shipping is reasonable. Sometimes it is.Both the Schlumberger and the Metrix have an interesting and surprising (to me at least !) printer port at the back !!! Yes, a printer... in something that does not even have a micro in it, how can that be... glad I have the manual for both of these instruments, I have all the technical detail about it.Well most of you probably know what it is, I guess, but I didn't so I was quite surprised to see this ! Before the advent of GPIB , manufacturers had found this clever way of outputting the measured value so it can be printed or recorded on some purpose made peripheral. Basically what they did was run the BCD outputs of the various counters to the back, and add some control signals so that the peripheral knows when to sample/record the BCD outputs. In the case of a counter, it's easy, you just use the gate trigger signal...Obviously you need quite a large number of pins, 4 BCD lines for each and every nixie tube, plus one or more control signals, plus ground.So in the 5 digit Schlumberger this all fits in a DB 25 connector, but in the 8 digit Metrix, they had to use a DB 50 plug ! These are not so common place...They both use different control signals too. So clearly there was no standard describing this interface back then...Anyway, the Metrix is compact, has good performance, so I decided to actually use it as my primary counter, rather than having it gathering dust. I will see for a more modern counter later, when the need arises and money permits !It has a nice internal design, with boards plugging into gold plated connectors, which all look like new and no doubt helped with reliability over the years...It does need a tiny bit of "restoration" though : as you can see from the pictures, there is a knob which is not original and looks out of place and really uglifies ( "beautifies" does exist, so why not "uglifies" ?! LOL ! ) the front panel ! That red capped black knob toward the left. Brr... I need to find an original knob ! not an easy task though !I love this Metrix, so I thought I would design a little interface/Adapter that I could stuff on the "printer" port at the back, so I could do some data logging/experiments. Shouldn't be too complicated, I want to start work on this pretty soon and hopefully have something working by year end.Obviously I might as well try to make it flexible enough to be used on the Schlumberger too, or any future instrument (not just counters) of this era that I might acquire in the future. Well, I mean electrical compatibility... mechanically obviously I would still need to make a little adapter since the counters don't use the same size connectors.Anyway, time to shut up and attach some pics ! First the Schlumberger then the Metrix.

author: Vince
author_rank: Super Contributor
timestamp: October 06, 2017, 09:59:32 pm
content: Next, the Metrix DX446A

author: bitseeker
author_rank: Super Contributor
timestamp: October 06, 2017, 10:19:14 pm
content: Nice ones, Vince, especially when they include manuals and schematics!

author: Cubdriver
author_rank: Unknown
timestamp: October 07, 2017, 01:29:55 am
content: Nice, Vince. And just to clarify, the seven segment neon displays are panaplex. Numitrons are also seven segment, but they're incandescent. And yes, I think they were common in gas pumps not too terribly long ago. Welcome to the merry bunch of nixie nuts here.-Pat

author: Vince
author_rank: Super Contributor
timestamp: October 07, 2017, 01:50:42 am
content: Thanks for the clarificationYeah I love these old glowing things, so much charm !Now that I am back into electronics, and also into wood-working, I am planning on making a few little "retro" looking gadgets using these lovely displays.Looks like the most difficult part will be finding suitable displays, at a suitable price ! :-/I guess I will have to hunt the for every affordable old shitty piece of gear that's worthless and just salvage the displays from it...I hear some people are making new nixie tubes but I don't know where to buy them... except for that guy in eastern Europe but at 250 buck a pop no thanks, plus he only does mega huge nixies, basically to build clocks and what not... but he doesn't do small displays suitable for instruments or home appliances.I hear a couple people i Russia still make some... but I don't have names or address/website, just rumors that they exist... a bit thin isn't it...

author: Cubdriver
author_rank: Unknown
timestamp: October 07, 2017, 01:57:59 am
content: There still seem to be plenty of surplus Russian ones available on the 'bay - I'm not certain of the number off the top of my head, but think it's the IN-12. They're top view, sort of flat sided ovals similar to what HP used in a lot of gear in the 60s.-Pat

author: neo
author_rank: Super Contributor
timestamp: October 07, 2017, 02:12:25 am
content: Buying an HP 5340, in my experience, is alot like playing russian roulette. Mine is almost perfect but will only display to 3 digits due to some odd glitch.

author: Vince
author_rank: Super Contributor
timestamp: October 07, 2017, 02:17:57 am
content: Quote from: Cubdriver on October 07, 2017, 01:57:59 amYou mean the kind of package that Dave Jones used in this video ?Yes these would do nicely indeed.]https://www.youtube.com/watch?v=7uogKucrPks

author: Cubdriver
author_rank: Unknown
timestamp: October 07, 2017, 02:18:57 am
content: The common Russian ones are IN-12s, I just looked it up. I got a surplus box of 25 a while back for $50-60, IIRC.-Pat

author: Cubdriver
author_rank: Unknown
timestamp: October 07, 2017, 02:21:46 am
content: LOL - yep - them's the critters. The only thing I don't like about a lot of the Russian ones is that they use an upside-down '2' for the '5' character. Smart from an economic standpoint (one less shape to stamp out), but less so from an aesthetic point of view. Not that they cared about aesthetics, of course, and they are certainly functional.-Pat

author: Vince
author_rank: Super Contributor
timestamp: October 07, 2017, 02:23:52 am
content: Quote from: neo on October 07, 2017, 02:12:25 amYeah you might be right ! Actually just an hour ago someone I know (the chap I got my TDS 544A from), said he has jsut one of those, what do you know !... got it for free at that, an actual dumpster find ! Says the unit is in a very sorry state and that it had a few bad connections in the wirgin which he failed to locate...So yes, I am fully prepared for this kind of joy... and that's why I will only buy one if it's cheap enough and in good cosmetic condition, no broken or missing knob to start with. Not going to pay 250 bucks for it, but up to 100, if in good nick, I would go for it...

author: neo
author_rank: Super Contributor
timestamp: October 07, 2017, 02:27:46 am
content: I always liked the upside down 2.

author: Vince
author_rank: Super Contributor
timestamp: October 07, 2017, 02:30:19 am
content: Quote from: Cubdriver on October 07, 2017, 02:21:46 amYeah it looks weird indeed, don't like it either so would do all I can to find a model with a "proper" 5 digit.Still, you got a bunch of them for very cheap, so worth using themThe chap who sold the two nixie counters to me, also told me that a few other Nixie counters he had, would not find any buyer no matter how low the price. So he eventually resorted to pulling all the tubes from them and made a little fortune, sold all the tube for 15 Euros a pop in an eye blink ! So they are definitely sought after these days..

author: Vince
author_rank: Super Contributor
timestamp: October 07, 2017, 02:35:16 am
content: Quote from: neo on October 07, 2017, 02:27:46 amWell, maybe one day I will look at it differently and grow fond of its "funkiness ", you never know ! Maybe one days they will cost a fortune precisely because of their uniqueness of design... so maybe I will get some anyway, but if I have the choice, for the time being at least, I would prefer a proper 5.Certainly not a show stopper at any rate !

author: Vince
author_rank: Super Contributor
timestamp: October 07, 2017, 02:38:51 am
content: About the HP 5340A, a quick search on Google reveals that the service manual is available ! So at least there is a reasonable chance of being able to fix them, if one is willing to spend many an hour probing the thing...

author: neo
author_rank: Super Contributor
timestamp: October 07, 2017, 02:49:59 am
content: Quote from: Vince on October 07, 2017, 02:38:51 amI have yet to get mine working, at this point i would need much more sophisticated test equipment or a donor machine. A miracle would also work.

author: Vince
author_rank: Super Contributor
timestamp: October 07, 2017, 02:56:19 am
content: Well when you get reaaaaally tired of trying... just sned it my way, I will give it a fresh look, might work !No ? Well, I tried...Year end is approaching, ie miracle time, just what you asked for !So... just ask Santa to bring you courage and luck for Xmas !

author: Cubdriver
author_rank: Unknown
timestamp: October 07, 2017, 03:11:45 am
content: One of the issues with the 5340A in my experience is a custom IC in the signal path that gets fried. I have one at the back of my bench that has this problem currently. (I am also planning to try to help neo out with his blanked digits issue, hopefully soon, when I get back to it.) I got a replacement board from the bay that (fingers crossed) has a good IC, but haven't gotten to confirming everything else around that circuit is good in order to install it. I got hung up earlier in the summer by not having a short enough extender card (the board has a coaxial cable running to it, and there wasn't enough slack to use the long extender I had on hand); I ordered a short one and it got lost for a while on its way through Philadelphia, and during that time the mess on the bench grew to envelop the counter. I'm working my way back to it. (Patience, neo!)I'm pretty certain that the deceased part is the nearly unobtanium custom Schmitt trigger IC - the large rectangular part with the SS cover at the top right of the A22 board:Tonight's project is to shoot a few more pics of the Fluke 8200A and put it back together and get it off the bench and out of the way, and hopefully get a teardown thread of it up in the next few days.-Pat

author: tautech
author_rank: Super Contributor
timestamp: October 07, 2017, 03:12:54 am
content: Quote from: Vince on October 07, 2017, 02:17:57 amThere's a forum thread on those and a series of vids that hasn't been linked in this thread.https://www.eevblog.com/forum/blog/eevblog-948-nixie-tube-display-project-part-1/

author: neo
author_rank: Super Contributor
timestamp: October 07, 2017, 03:31:45 am
content: Quote from: Cubdriver on October 07, 2017, 03:11:45 amI like to see the situation as me being patient with only the occasional reminder left where you can see it and completely innocuously.In all seriousness thanks a lot for your help on such matters, it is how i work best. With someone helping me and someone to bounce ideas off of.

author: Vince
author_rank: Super Contributor
timestamp: October 07, 2017, 04:13:02 am
content: Thanks for the lnik Tautech.Cubdriver, thanks for the info and pretty picture, all that gold ! Makes me want to have one these machines even more, it's a jewel !I don't have the service manual but looking at your pics, I assume that the coax cable comes from the RF pre-amp, and that Schmitt trigger must be shaping the signal in order to drive properly the RF frequency divider which I assume must be those 4 golden DIP packages sitting on this gold plated ground plane ?No less than 4 chips... I guess it's much needed if one wants to get the 20GHz input signal down to something the counter can cope with.So, two thought immediately come to mind :1) This board/SS can only concerns the RF prescaler board/input, so I guess this means that if you use the low frequency input, the counter works just fine ? So this custom part failing, does not actually render the machine completely useless, better than nothing !2) Given that the function of this SS can is well identified, and that it is a basic/simple function rather than billion gate ASIC... couldn't there be some hope, short of finding an original replacement part, to substitute a modern part for it ? I mean, 20GHz was no doubt a big deal back then, but is quite trivial these days, RF components can be readily ordered with a mouse click and a few bucks.... maybe there exist Schmitt trigger devices these days too ? Worth investigating...Obviously it probably wouldn't come in the same SS can foot print, but as long as it functional... and well maybe it would be possible to "stuff" the old can with the modern replacement part, to keep the original look... if one wanted to go extreme about it.

author: Cubdriver
author_rank: Unknown
timestamp: October 07, 2017, 04:28:27 am
content: No worries. The counter sitting on the bench serves as a constant reminder. I foolishly volunteered to help my best friend paint a coworker's newly purchased house. There is some king of confluence of idiocy there that makes us unable to work efficiently - what was supposed to be a week-and-a-half to two week project working in the evenings has somehow entered its third month (with a few breaks for business travel, but still...) This time sink has been doing a fine job of hamstringing my other efforts. Thankfully, the end is finally in sight and we hope to be finished this week.THEN perhaps we'll continue with the HP 5340A misadventures!-Pat

author: Cubdriver
author_rank: Unknown
timestamp: October 07, 2017, 05:25:14 am
content: Quote from: Vince on October 07, 2017, 04:13:02 amPretty good assumption, Vince - the coax is the input from the direct count amplifier. Unfortunately,allthe frequency signals pass through this Schmitt trigger, low and high. (Blue below is the high frequency 50 ohm input; pink is the lower frequency high impedance input, and green is the A22 board.) From there it goes to the count register, then the display register, and on to the glowie numbers those of us in this thread all love so much.Overall counter block diagram:And I have considered trying to just substitute a modern IC in the place of the custom jobbie, and may yet wind up doing that. I first wanted to try to fix things without reinventing the wheel if possible. It's also remotely possible that there is something else amiss with that board, but I'm pretty sure that with the limited probing I was able to do while it was plugged in that I had signal at U9's gazinta, and a lot of nothing at it's gazoutta. I need to poke at it while it's on the extender card.A22 schematic:A22 block diagram and layout:-Pat

author: Vince
author_rank: Super Contributor
timestamp: October 07, 2017, 03:09:27 pm
content: Thanks for the details Pat. I wouldn't dream of fixing these complex beasts without the service manual, that's for sure...Now that you have the adequate extender board you will be able to work much more comfortably but from what you say indeed it looks like it's a done deal sadlyI am starting to get the impression that this particular model is well known, and not just in the US, so maybe at some point, as people collect them, there will be enough people affected by this problem to warrant a collective effort in designing a replacement. This RF stuff is a specialist job of course but maybe there are enough collective knowledge in this forum or out on the web, to allow one to embark into designing a replacement...That would be a nice little project for RF design aficionados ! Maybe we could ask Shariar/ The Signal Path, and Alan / w2aew what they think of it from a design perspective, if it's feasible or not, realistically... that could make for an interesting video for them to do !I think I might contact them about it... both being in the US, I guess it would not cost too much for someone in the US, owing on of these machines, to ship it to them (along with the much required extended card of course, and a copy of the printed service manual if not available in PDF form for them to download). They have the academic and practical knowledge to tackle this, or at least provide us with a well informed insight, as well as the expensive equipment required to play with this thing at will.Hell... the two of them know each other, why not combine their expertise in a joint video ?! A co-produced video... I guess they live too far apart from each other to actually meet physically, the US being a vast place, but they could still communicate via e-mail to discuss this.I just downloaded a copy of the service manual... sadly 99% of it is impossible to read, the PDF is massively corrupted somehow. I could only figure out a few snippets here and there, but OMG I see that this instrument came with GPIB ?!!And the manual is date 1975 ! Sure, HP invented this bus so I understand that they were the very first to implement it on their instruments, before other manufacturers adopted it, but still, 1975 ?!! There was not even an 8 bit micro to run such a thing back then, I think ! Had a quick look on Google to refresh my memory, found an article from 1974 announcing a super duper 4 bit MCU...The PDF was really too fucked up so I couldn't see how they did it... my assumption is that they did not use an 8 micro which did not even exist probably, or elese they might have used it to control the front panel and give their instrument a competitive edge in terms of user interface.... so my guess is that they designed their own stand-alone bus controller, a big state machine, which would not necessitate a micro ti run it ? I am intrigued !Also saw that this beast is really complex, found a snippet about a PLL ?!That machine was indeed a marvel of engineering compared to my French nixie counters or the same era !I want one of those, definitely, working or not !!!

author: neo
author_rank: Super Contributor
timestamp: October 07, 2017, 04:58:18 pm
content: Do you know why it is so complex and nice? Back in the 70s when they sold these units they cost between 12-17k depending on the options. Doesn't sound like much i know but accounting for inflation that is about a 100K in today's money, thats in freedom dollars.You see the HP office manager who ran the office that designed these only cared about the products efficiency to do its job and its ability to do it accurately, he didn't care the cost because to him no cost was too high. This one model of counter had over a 20 year life that i think stands as proof of his genius and commitment to the design.

author: bitseeker
author_rank: Super Contributor
timestamp: October 07, 2017, 05:11:01 pm
content: Quote from: Cubdriver on October 07, 2017, 05:25:14 amHey, Pat, watch out with all those highfalutin, technical terms. You must think you're talking to a bunch of engineers or something.

author: Vince
author_rank: Super Contributor
timestamp: October 07, 2017, 06:04:23 pm
content: Quote from: neo on October 07, 2017, 04:58:18 pmAh yes, I am sure 15K or so was a very considerable amount back then !amazing they can bought for so cheap these days... definitely want one !Quote20 years ?! Not in Nixie form I guess ? I gather they made a revised version of this model, that used an LCD display ? I guess that helped keep it on the market for so long.I bet the LCD versions sell for much more, because they look more modern, even though deep down its gutts are the same as the old original Nixie version ?That's great... this way we can have a super duper counter for cheap, and at the same time enjoy these lovely Nixei tubes....Definitely worth investigating a way to replace that custom schmidt trigger can, to extend the life of these lovely beasts...

author: rsjsouza
author_rank: Super Contributor
timestamp: October 07, 2017, 06:41:44 pm
content: Quote from: Vince on October 07, 2017, 06:04:23 pmThe HP page below indicates the original price was US$5340.00 (about US$100k today) and it seems it used Nixies until the end. Quite remarkable.http://historycenter.agilent.com/exhibit1

author: Specmaster
author_rank: Super Contributor
timestamp: October 07, 2017, 06:47:25 pm
content: Heres my first nixie tube device, I like it.

author: Vince
author_rank: Super Contributor
timestamp: October 07, 2017, 06:55:42 pm
content: Quote from: rsjsouza on October 07, 2017, 06:41:44 pmHmmm, thanks for that link, very interesting !Introduced in 1973, and retired in 1994 still with Nixies in it, wow !The article confirms that it was a real beast and intended that way, rather than your average instrument.With such a long life, they must have built a good number of them, and they must have had time to spread all over the world... so maybe I do stand a reasonable chance of finding one in good nick at a decent price, one day. Brings a big smile to my face already !

author: Vince
author_rank: Super Contributor
timestamp: October 07, 2017, 07:02:44 pm
content: Quote from: Specmaster on October 07, 2017, 06:47:25 pmHmmm looks real cute indeed, I like it too !

author: richnormand
author_rank: Unknown
timestamp: October 07, 2017, 07:12:16 pm
content: EGG 550-1 radiometer/photometer.I use it with a fiber optic attachment to map the 360 degree illumination of LEDs.Got it cheap as one of the Nixie tube was dead. Turned out it was the driver chip (DS8880).Five minutes with the soldering iron and it has been in use for more than 10 years now.

author: Vince
author_rank: Super Contributor
timestamp: October 07, 2017, 07:32:34 pm
content: Not your average instrument for sure, interesting piece of gearGlad you got lucky with the repair and got yourself a good deal in the end !

author: neo
author_rank: Super Contributor
timestamp: October 07, 2017, 11:26:19 pm
content: Quote from: rsjsouza on October 07, 2017, 06:41:44 pmThe advertisement i saw said 15k with all options, and no it was not nixie tubes all the way in the 80s they switched over to LEDs.Admittedly at the price point of these beasts if someone asked for nixie tubes and was willing to pay a bit more i'm sure they would consider it an option.

author: Vince
author_rank: Super Contributor
timestamp: October 08, 2017, 12:12:29 am
content: That website looks like the official Agilent/ HP website, so if even THEY can't get their own product history right... I am worried ! LOLSo I guess this needs more digging....

author: Cubdriver
author_rank: Unknown
timestamp: October 08, 2017, 01:27:07 am
content: Quote from: Vince on October 07, 2017, 03:09:27 pmIndeed! It's nice that so many of the manuals are available as scans, often for free from HP/Agilent/Keysight, BAMA or KO4BB, but sometimes you 'get what you pay for' in that their resolution leaves a lot to be desired. For guaranteed good scans, Artek Manuals is a safe bet - Dave's stuff is top notch in that department, and considering the effort involved in doing the scans, he sells them for a song.One thing I always try to do is to get an actual paper manual for every piece of gear I get. Scans (if clear) are great to have, but nothing beats the huge fold-out schematics in the original manuals, and I find it much easier to flip back and forth with paper pages rather than scrolling hither and yon constantly with a scan, especially for something like the 5340A where roughly the last quarter of the manual is all fold outs. Yeah, you can print scans, but then you often get to play cut-and-paste to put the pages together if it's going to big enough to be legible.QuoteYep. Now to clear the bench a bit and get back to it...QuoteThat might be an interesting project for one or both. I need to dig a bit more into what that IC does in the circuit; perhaps there might be a simple modification that would enable something modern to be used in its place. That would be nice, if so! If the replacement board I got has the same issue and doesn't fix it, I will likely start with an inquiry on the HP mailing list to see if any of them have any ideas.QuoteI just did a quick search of my usual spots (Keysight, BAMA and KO4BB), but none of them seem to have a PDF of the manual, so apparently there's no easily available clear copy.The HPIB apparently debuted in 1972:http://www.hp9825.com/html/hpib.htmlMy understanding is that in fact HP got into the computer business in an effort to provide automation with their test instruments. Ironic that 30-40 years later the tail grew so big that it parted company with the dog and went out on its own.QuoteYes, it never ceases to amaze me just how much they were able to do with what technology they had. Those early instruments are stuffed full of circuitry, unlike modern stuff where there's one IC with a gazillion pins & 37 character long part number, an LCD screen, and a power supply inside an otherwise empty enclosure (ok, I know that's something of an exaggeration, but notTOOmuch of one!)I hope you manage to find one (working, or at worst only needing minor repair). It is certainly a very fascinating piece of hardware! I believe it was introduced in 1973, and at the time had a list price of $5300.00. Add another $400 for the OCXO, $100 for the inputs on the rear panel (useful for fixed test setups in racks, I suppose), and another $350 for the HPIB option. It was not cheap, which is likely why so many still exist - it's built like a tank.http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1973-04.pdf-Pat

author: Cubdriver
author_rank: Unknown
timestamp: October 08, 2017, 01:28:48 am
content: Quote from: bitseeker on October 07, 2017, 05:11:01 pmMy apologies!I'll try to keep that in mind for future posts.-Pat

author: edavid
author_rank: Super Contributor
timestamp: October 08, 2017, 01:33:33 am
content: Quote from: rsjsouza on October 07, 2017, 06:41:44 pmNo, that is wrong. There was a later LED version (see photo).

author: Cubdriver
author_rank: Unknown
timestamp: October 08, 2017, 01:45:27 am
content: Quote from: Vince on October 07, 2017, 06:04:23 pmThey had nixies up till 1982 or 1983, IIRC, then switched to seven segment LEDs - would need to look at my catalogs to find out for certain when the transition was. In '86 list price for the LED version was $12,500; +$750 if you wanted the OXCO; +$200 for the rear connector option; +$600 for a frequency extension that let it measure up to 23GHz; $500 for an input protection limiter; and $550 for HPIB.I just looked at my catalogs; it appears up to the 1994 one, but is gone from the 1996. (I don't have a copy of the '95 catalog yet). By the 90s, it was listed as a 'mature' product, meaning it was not a regular production unit, but if you had one written into your certified test procedure and it died and a replacement was needed to save gazillions of dollars of recertifying a new test setup with a different model of counter, they'd build you one. In '94 it listed for $23,500/$1200 for OCXO/$325 for rear panel input /$760 for range extension/$1300 for input limiter/$1100 for HPIB.It certainly had an impressive run!!-Pat

author: Vince
author_rank: Super Contributor
timestamp: October 08, 2017, 02:13:25 am
content: OK ! So we have it all figured out for certain now, thanks !So indeed Agilent was wrong on their own website talking of their own products, scary.I will have to be careful not to buy an LED version by mistake ! I mean, for example if I come across a unit that doesn't power up at all or with nothing on the display and the seller is unable or unwilling to help figure it out...Would also have to be careful that it does come with HPIB, can't believe that it was not standard on such an expensive and state of the art instrument !As for the OCXO I don't really care since I would use an external reference so.... I hope it does have the usual external 10MHz input as standard...Artek yes, very good indeed ! A year ago I purchased a manual from them for one of my old scopes, a Tektronix rack mount 5111. The schematics I found on the net were shitty so I searched ebay and come across an ad from them. Didn't know anything about them back then, but it was very affordable (even with the shipping to France) with regard to the quality that was promised, so I didn't have much to lose, went for it, hoping for the best and expecting the worst as always with something new... I was hardly disappointed, 5 star work indeed !It's only later that I figured he was well known, even found him lurking on the "TekScope" Yahoo forum/mailing-list.I would buy manuals from him anytime for sure !But as Pat said nothing beats a proper original printed manual... that's why I was overjoyed to have them with my too Nixie counters, and also my old WaveTek 75 waveform generator.Failing that, I think I might invest in a little A3 format inkjet printer. I remember seeing one from Samsung for very little money. Sure it must cost an arm with the cost of ink, as always with consumer grade inkjet printers, but it would not be much of an issue since it would only be used every now and then, and only for BW printing (printer had a distinct and large capacity black cartridge ISTR). One advantage of a printed PDF is that you can handle them "carelessly" on the bench and write on them at will to take notes of voltages or other information you gather while probing around to debug the instrument... which I would obviously not do on an original manual !Obviously having both the paper manual and a nice PDF with an A3 printer would be ideal...And I quite liked the gazinta and gazoutta .... had me wondering for a bit but once I had sussed it, made me laugh, quite fond of them already, please don't discard them in future posts, that will be your trademark !

author: bitseeker
author_rank: Super Contributor
timestamp: October 08, 2017, 02:51:10 am
content: Quote from: Vince on October 08, 2017, 02:13:25 amPrecisely. In low-res photos they can sometimes be fuzzy enough to look somewhat similar.Quote from: Vince on October 08, 2017, 02:13:25 amLOL! Yeah, just giving Pat a hard time once in a while. I'm sure he's got more where that came from.

author: neo
author_rank: Super Contributor
timestamp: October 08, 2017, 03:25:42 am
content: Quote from: Vince on October 08, 2017, 02:13:25 amIt does in fact have 10MHz reference in as standard, at least as far as i know.

author: Cubdriver
author_rank: Unknown
timestamp: October 08, 2017, 04:02:58 am
content: Vince -The transition to the LED display seems to have taken place between 1982 and 1983 - the former catalog shows and describes nixies and the latter LEDs. You'reprobablysafe with serial number prefixes of 21xxAyyyyy and lower.-Pat

author: Cubdriver
author_rank: Unknown
timestamp: October 08, 2017, 04:10:36 am
content: Quote from: Vince on October 08, 2017, 02:13:25 amIt does in fact have a 10MHz reference input; it needs a sine or square wave at ~1.5V p-p into a 1k ohm input impedance. "Normal' versions of the counter have a crystal oscillator for a time base; Opt 001 is the high stability OCXO.-Pat

author: Gyro
author_rank: Super Contributor
timestamp: October 08, 2017, 10:09:04 am
content: Quote from: richnormand on October 07, 2017, 07:12:16 pmNot Nixie but Panaplex... and very nice too!

author: Vince
author_rank: Super Contributor
timestamp: October 08, 2017, 03:42:42 pm
content: Thanks for the details Pat and Neo

author: neo
author_rank: Super Contributor
timestamp: October 08, 2017, 04:20:51 pm
content: Quote from: Vince on October 08, 2017, 03:42:42 pmNo problem, i like to talk about electronics, especially to a grateful audience.

author: richnormand
author_rank: Unknown
timestamp: October 08, 2017, 06:05:29 pm
content: Quote from: Gyro on October 08, 2017, 10:09:04 amYou are right, close cousins to Nixiehttp://imajeenyus.com/vacuum/20100814_panaplex/index.shtml

author: Vince
author_rank: Super Contributor
timestamp: October 08, 2017, 06:12:28 pm
content: Wow thanks for the link, that close up picture of this Panaplex is beautiful !Looks like some people actually manage to DIY their own panaplex ?!Jeez.... maybe someone one day will start upo a little company to make new Panaplex displays again, no problem with supplies and speculation on prices any more, how marvelous that would be...

author: Specmaster
author_rank: Super Contributor
timestamp: October 08, 2017, 06:40:27 pm
content: I agree far superior to nixie tubes anyday and brighter than LED's.

author: bitseeker
author_rank: Super Contributor
timestamp: October 09, 2017, 01:51:09 am
content: Yeah, Panaplex seem to be a nice combination of characteristics from VFD (contrast), Nixie (amber glow), and segmented LED (variety of shapes in a single plane) displays.

author: Vince
author_rank: Super Contributor
timestamp: October 09, 2017, 05:06:05 am
content: They also ha ve the advantage of allowing very flat/compact package even for large sizes !Maybe we should rename this thread "glowing displays" LOL Nixies represent most of them in volume, but the other kinds of glowing are sexy too... and it would seem a bit ridiculous to start a new thread for VFD and another for Numitrons and another for Panaplex etc.... no ?......

author: bitseeker
author_rank: Super Contributor
timestamp: October 09, 2017, 07:26:36 am
content: Yeah, I was thinking "glowing displays," too. I'm not sure if the OP is around to change it, though.

author: macboy
author_rank: Super Contributor
timestamp: October 09, 2017, 02:12:18 pm
content: Quote from: Vince on October 06, 2017, 09:59:32 pmI see a Metrix MX-54C in one of those photos. If you haven't found it already, check out this thread:https://www.eevblog.com/forum/testgear/metrix-mx56c-bk-precision-5390-multimeter-teardown/. It has a lot of information on these meters, including links to data logging software and calibration software.

author: Vince
author_rank: Super Contributor
timestamp: October 09, 2017, 02:57:27 pm
content: Yep Macboy, I know about this thread, I participated in it a year ago or so... just replied to your post there a minute ago !

author: Gyro
author_rank: Super Contributor
timestamp: October 09, 2017, 03:23:01 pm
content: Quote from: bitseeker on October 09, 2017, 07:26:36 amHow about 'Cold Cathode displays' - we don't want to get overrun with nasty LED and fading VFD and OLED ones.(Although I guess LEDs are technically cold cathode).

author: mtdoc
author_rank: Super Contributor
timestamp: October 09, 2017, 05:30:40 pm
content: Thisjust showed up on my ebay Nixie Counter search alert. Looks like he got a good picture just as he let the smoke out...

author: bitseeker
author_rank: Super Contributor
timestamp: October 09, 2017, 05:35:57 pm
content: Yeah, I've seen that on some listings. Nothing like a thermonuclear detonation to inspire confidence in the item being sold.

author: Cubdriver
author_rank: Unknown
timestamp: October 09, 2017, 06:02:22 pm
content: I've seen that one before. He's on crack if he thinks he's getting $250 for a 5233L, especially with no photo. I don't care if it DOES include the oval power cord.-Pat

author: bitseeker
author_rank: Super Contributor
timestamp: October 09, 2017, 11:03:42 pm
content: You can get quite a collection of vintage power cords going for that kind of margin, indeed.

author: bd139
author_rank: Super Contributor
timestamp: March 04, 2019, 04:30:37 pm
content: Thought this belongs here as well as the TEA thread...Heathkit IC-2108 in restoration.

author: Cubdriver
author_rank: Unknown
timestamp: March 05, 2019, 09:04:37 am
content: Mmmmm... Panaplex.-Pat

author: bitseeker
author_rank: Super Contributor
timestamp: March 06, 2019, 03:09:59 am
content: Yes!Here's wishing you a good deal on a replacement for the left-most module, bean.

author: TERRA Operative
author_rank: Super Contributor
timestamp: March 06, 2019, 12:05:30 pm
content: Quote from: snik on October 28, 2015, 02:43:03 amThat Philips PM 6607 is a Takeda Riken (Advantest) Digipet-60.I have one I restored that is exactly the same except for the brand name.I wonder who rebadged who....Here's a link to the Japanese manuals (with schematics) and restoration video.https://drive.google.com/folderview?id=1RzIU3xREXrsWJas6RXYgoC3eI_5fkioYhttps://youtu.be/amwk4wN4zY4

author: Enigma-man
author_rank: Regular Contributor
timestamp: May 25, 2019, 03:47:13 am
content: Looking back, I see my last posting was December 31, 2016. It is not due to anything or anyone on the site. What has prevented me is life ingeneral. Without going into detail, let me say multiple deaths in the family, six within a year starting with my wife in Feb. 2016 and in late January, 2017my brother-in-law. Also my mother suffered a life changing stroke two weeks before my brother-in-law died. My life was in turmoil and still is but not as bad asit was. My hobbies pretty much ended as there were more pressing matters to deal with which many of you have already experienced and for the younger folk, your turnwill come eventually.Recently, my generous friend who has given me practically all my 'Nixie' test equipment, has decided to downsize and his vision of a rack full of Nixie gear has nowfallen to me. I have four pieces to show in the upcoming posts. Three are fairly rare and one is not.Let me start with the rarest of the bunch. A Systron Donner Model 1032 frequency counter. It was working until the power supply blew.The unit is 100 per cent Germanium devices and has four Nuvistor tubes in the front end. In its day, somewhere in 1963 according to date stamps onthe transistors, it was state of the art. Nuvistors were new on the scene and everyone was eager to incorporate them in their designs.That was all great way back then. Enter the year 2019, fifty-seven years after it left the factory... Try and repair it. No service data and all hopes of itreturning to life are currently left to someone's years of knowledge... or lack thereof.What is noteworthy is, my buddy was sending it to e-waste for recycling had I not shown up to have a look at something else he was giving away.As soon as I saw the forward facing Nixie's it was mine. Condition wise it is nearly pristene considering its age. It was once in a technicalinstitute, (Northen Alberta Institute of Terchnogogy... NAIT) it was spared. I'm guessing Edmonton, ALberta. I've never heard of the place and Ilive in Canada a few provinces east. Back to the Sys Don... It needed a Hubbel twist lock power connector which my buddy had.He was also giving me two HP 5340's. One with the usual blown part that would switch over at 250MHz, but big deal, I'm not doing anything atthe moment that needs 18GHz. We search through a LOT of equipment but can't find them. I spot something in a large plastic bag and ask what itis. He don't know. It turns out to be something he was going to give me two years ago...It's a Dana Model 5330 5 1/2 digit Nixie readout voltmeter which will be seen next post.After that it is a Vidar Model 500 four digit Nixie voltmeter with frequency counter.The last one is the HP 5340, no big deal as there are a lot of them around and I've been following the previous posts of the attempts to get one working.Anyway, here are a couple of pictures of the Systron Donner. Sorry about the quality of them. The second one is a capture from a small video and the lightingwas not a priority, but it was working and will again.

author: Enigma-man
author_rank: Regular Contributor
timestamp: May 25, 2019, 03:50:27 am
content: Hmmm... First pic didn't show up, so here we go again.

author: Cubdriver
author_rank: Unknown
timestamp: May 25, 2019, 07:35:14 am
content: E-man, I'm very sorry to hear of your misfortune - it has obviously been a rough couple of years. My deepest condolences on your losses, and I sincerely hope that better days are ahead - it sounds like you're way overdue in that regard.Here's hoping that you have time to resume your hobbies once again and that your serendipitous arrival to save that beautiful SD counter from the dump is a sign of things to come!I have an SD of similar vintage waiting to be shipped home from CA, but the one I got looks like ten miles of bad road (or, perhaps more precisely, like it was dragged down ten miles of bad road behind a truck) compared to yours. I look forward to seeing more photos and getting this thread reignited.Welcome back!-Pat

author: Enigma-man
author_rank: Regular Contributor
timestamp: May 25, 2019, 04:01:01 pm
content: Thanks for that, Pat. What model is yours, newer or older. Maybe we can trade info and save each other time. I know the Model 1035 uses IC's so some boards will bedifferent from the pictures I saw.Concerning the Sys Don 1032, Germanium devices are not easy to come by and what a cross reference shows as a substitute didn't work for me.There is also the problem with the Tin plating on aluminum can devices that you most likely aware of concerning "tin whiskers" forming and shorting out devices.My unit worked for a short time after I swapped the two Nuvistors in the A side with ones from the B side and fed in an external 1 MHz clock. The xtal in the oven wasno good and there was problems with the oscillator plug in as well. It only worked when you pressed the reset button. Obviously a reset problem. On the reset anddisplay board was a 2N1671 UJT which was open. On the time base board there are five of them. I took the 10Khz one out and put it on the other board.No dice. It still didn't work. About a half hour later the power supply died. A 2N2138 date code 2-24 (62-24) was shorted. I have ZERO PNP Germanium power devicesso I subbed a silicon. The supply came back but I had no +6 volts. The +30, -30 and -6 were okay. I must have spent 20 hours on and off and to this day can't find anythingwrong. A few days ago the -6 disappeared. The 2 remaining power Germaniums are okay and so is the silicon one. I swapped out the germanium drivers and still no dice.It isnt't a cap problem since it was the first thing I suspected. This makes no sense to me and refreshing what I learned decades ago about Germanium, they are leaky devices.If it comes down to what I think will be inevitable, I will run an external +30 -30 +6 -6 volt switching supply. The internal +250 won't be bypassed since it doesn't needregulation. 100% restoration to original may not be possible and beyond my control. As long as it works is the main thing.Another tidbit... A 2N2646 UJT is not a substitute for the 2N1671 no matter what you read. The circuit will have to be modified.Also a 2N1305 is not a substitute for any low power PNP Germanium. I found an old Radio Shack Transistor Cross Reference book dated 1986.Every low power PNP Ge device was referenced to the only one thery sold and it was the, you guessed it, 2N1305. I call BULLSHIT !!!!! and loudly...I tried it on the time base board and it wasn't a suitable replacement. The frequency is not high enough, there is too much or too little leakage.Back in the 60's and 70's it would be no sweat to find the devices you would need to get the unit back up and running. Today is a different story.I will post a few pics of the boards next post.

author: bitseeker
author_rank: Super Contributor
timestamp: May 25, 2019, 04:43:53 pm
content: Welcome back, Enigma-man! Sorry to hear about the tumultuous times you've gone through these past few years. So good to see you back.That 1032 is cool. I have never seen one before. Thanks for rescuing it from recycling! It'd be great to have a thread dedicated to its restoration, which will also be a way to start building a repository of knowledge about it.

author: Enigma-man
author_rank: Regular Contributor
timestamp: May 25, 2019, 05:41:45 pm
content: A dedicated thread may be the way to go, but might not get to full restoration thus letting down thread followers. I'll think about it.In the mean time here are some board pics. The time base needed repair as the 1Hz wasn't working. I replaced the 100K trim potas it was quirky when adjusted. The 100Khz still isn't working and is a transistor issue. Two transistors were open and my subs don't work.The cap on the far right is temporary. I wanted to see how the 1Hz section was affected and it's just a matter of readjusting the 100K trim pot.No big deal. This board has a marked slot and won't work in any other slot. It is slightly different than the 250KHz and 25KHz boards due to using high speedGermanium devices. The 25K board also has different transistors. The four 25K boards can be in any of their marked slots as they are all the same.I`m pretty sure any Ge PNP would work as a flip-flop. I'll try it when it's up and running again. Only the high voltage transistors are the same onall six counter/display boards. If one of them dies, it's a silicon or nothing sub.I think it is possible to get this unit functional, but 100% original maybe not. My buddy is looking for some Germanium devices or a beyond hope ofrestoration donor. Fingers crossed and hopefully I won't have any more "Whiskey Tango Foxtrot" (WTF) with the "F" bomb dropped so many times I could fillseveral swear jars (big ones) to capacity...Here's the pics...

author: Enigma-man
author_rank: Regular Contributor
timestamp: May 25, 2019, 05:49:15 pm
content: Ooops. Forgot the time base board.

author: bitseeker
author_rank: Super Contributor
timestamp: May 25, 2019, 06:16:13 pm
content: Hopefully, you'll go for the dedicated thread. It could help with sourcing donor parts, too.Those boards are so beautifully done (and shiny!).

author: vk6zgo
author_rank: Super Contributor
timestamp: May 26, 2019, 03:26:10 am
content: Quote from: Enigma-man on May 25, 2019, 04:01:01 pmBack when I worked at a TV Studio, we had some books with very extensive equivalents lists.The ones with abridged specs were reasonably good, but those with just straight side by side listings of devices with their "equivalents" were pretty much a waste of paper.The funny thing, is those books were around for years, even going into multiple editions of completely misleading crap!If I couldn't find an equivalent using the books with specs, I looked at equipment which did the same job, with similar circuit layouts to see what devices they used.Of course, this is easy enough to do in a place with a lot of service manuals, & when looking for silicon devices!

author: Cubdriver
author_rank: Unknown
timestamp: May 26, 2019, 07:01:43 am
content: E-man, I have no idea what model mine is - I've only been able to find a couple of crappy cell phone pictures taken in my hotel room, and the model number can't be seen. I hope to find time to box it up and ship it back the next time I make it out to CA. My recent visits have been too hectic to get packing materials together and box it up.Here's one of the pics; it's upside-down in this photo. It's unusual in my experience because it's a bottom loader - I'm used to cards plugging in from the top side of the instrument. My suspicion is that it may be older than yours is, but could be wrong.I will have to look at the memory cards for my DSLR - I can't believe I got a new toy that I wouldn't get to ship home right away and wouldn't have taken more than three pictures with the cell phone...Edit to add a pic of the nixies beginning to awaken from their long slumber:-Pat

author: Enigma-man
author_rank: Regular Contributor
timestamp: May 26, 2019, 03:02:27 pm
content: Any info on older Systron Donner equipment is virtually non existent. I saw a reference to a Model 1035 a few weeks ago. Today my search shows zippo...I think yours might be newer since it has seven readouts, mine has six and the cards are tiny compare to the 12.5 inch long ones in my 1032. Yoursmay have IC's and if it does, it's definitely newer. Pull a card and check the date code on devices. That will tell you.Older or newer, regardless of model, not many are around.Once you get it back home and clean it up, it will be a fine addition to your collection. Nice find, man.Wait a second, this looks like it might be Australian... Upside down boards...Just kidding. No offense meant to the fine people waaaaay down undah.Edit:The unit I came across was a 1037-5 not a 1035 and probably why it doesn't show up on a search. The 1037-5 is a 50MHz unit, still with 12.5 inch plug in boards, but uses IC's

author: Enigma-man
author_rank: Regular Contributor
timestamp: May 26, 2019, 05:44:26 pm
content: Here is the next piece of gear for show and tell. As I mentioned yesterday, I was given a Dana 5330 5 1/2 digit voltmeter by my buddy. He never turned the unit on and it sat in his basement stored away for probably close to twenty years. As I was carrying it in, tucked under my arm, I thought I heard something move around inside the unit. I gave it a gentle shake and there was definitely something loose inside. I figured some component fell out somewhere. I was curious and removed the top cover which was held by a single Phillips screw. At first I didn't see anything obvious, then noticed a vacuum tube box in the far left corner. Whiskey Tango Foxtrot ?What's a tube doing in here ? Then I noticed another Westinghouse tube box on the right rear corner.??I picked up the box and nearly fell over. Two brand new ZM1000 replacement Nixie tubes in never opened boxes !Never have I come across spare components inside any unit other than fuses. Whatever I had planned for the afternoon was "I'll get to it tomorrow"...After further examination, I could not see any signs of repair. Either it never was repaired, or if it was, the repair person was very honest and left the tubes. They could easilyhave been expropriated. I found a power cord and plugged it in. It powered up, but the display was jumping around. I set it to autorange and it settled down.I was hoping it was a true multimeter, but it is just a voltmeter. That's okay, it's 5 1/2 digits. The next question was, how accurate is it at the moment. I hooked upmy AD688 precision +10.0000 and -10.0000 reference to it and it showed +9.9988 and -9.9852. Not too bad. Back in February this year, my good buddy gave me aWeston Standard Cell. Up until the mid 90's the Weston Cells were the worldwide voltage standard. They were replaced by the Josephson Junction. You can read up on this stuffon the net. A new Weston Cell was 1.01830 volts. The cell is only supposed to be guaranteed accurate for a number of years but I have read some are still good after many decades.I don't know how old my cell is but I made the adjustment to 1.01830 as quickly as possible. The cell needs recovery time and the longer you pass current through it the longer ittakes to recover. If it shorts, it may take 5 weeks to get back to 1.01830 volts. Since I don't use it regularly, the next time it's used it will be okay.I know this isn't the best way to calibrate the unit, but it is accurate enough for my purposes.All in all, this was a good find. Cosmetically it is not great. The display bezel took a hit somewhere along the line and has a large crack in it. I will get some tinted plexi andwith a heat gun remove the Dana plate and reglue to the new one. A flat black paint job and maybe one for the top cover and its fully restored.I am glad that it didn't need repair. It's old RTL technology. Repairable yes, but even the RTL devices are rare.Here's a few pics. The inside is just RTL chips and normal stuff and the input module won't show you anything so I didn't take any pictures.Edit for another typo...

author: GreyWoolfe
author_rank: Unknown
timestamp: May 27, 2019, 02:00:06 pm
content: Here is my contribution. Fluke 8400A bought for $2 at a ham radio tail gate party. Not sure what to do with it because of its size. Voltage readings aren't bad, resistance is all over the park. I haven't decided if I want to try to recap it yet because I really don't have a place for it. Plus, the service manual is 5X the cost of the meter!!! It is nixies though.

author: Enigma-man
author_rank: Regular Contributor
timestamp: May 27, 2019, 02:50:46 pm
content: Not bad for 2 bucks. Recapping probably won't make the ohms problem go away. Sounds like a board problem .A saw a thread where a member here named neo had or has a manual for the 8400A. He's in the US like you. Maybe contact him and see if he'swilling to help.

author: Enigma-man
author_rank: Regular Contributor
timestamp: May 27, 2019, 05:26:35 pm
content: The last one I have to show, for now, is this rare Vidar 500 Voltmeter with frequency option built in. Late 60's or early 70's. Initially, I was going to use it as a donor for my Systron Donner 1032 as a source ofGermanium devices. That was until my buddy shows up this last Thursday "with something for me". Along with an HP 5340A Frequency Counter and two diesel locomotive speedometerswith Beckman Panaplex displays, he pulls out what's in the second picture. ARE YOU KIDDING ME ? The service manual for one of the most obscure pieces of equipment. It looked like itnever was opened. I could not, in good conscience, not give the Vidar a chance to be functional.I had a go at it this weekend and even with the manual, it will be a challenge. Some boards have that polyurethane or whatever coating on them and a probe can't be easily placed where you need to take measurements. The unit has had several repairs. The auto range board has two different relays, the two main boards have seen repair as was another board with a USAF 2N404 as a replacement dated 1967. I poke around and the voltages were okay, but a 10 ohm resistor was discoloured from overheating so I just replaced. There was nothing coming out of the 60Hz time base section and two 2N2925's were open. 2N3904's made that section work again, but it still didn't indicate nothing but 0000There is a reset pulse but no count pulse from either the voltmeter section or frequency counter even though all sections seem to be working.This thing has both Germanium and Silicon devices. Making board extenders isn't going to happen because the plug in scheme is like you see.I will likely leave this for another time. Anyway, here is what it looks like.When this gets working, I'm calling it Darth Vidar...

author: Cubdriver
author_rank: Unknown
timestamp: May 27, 2019, 08:22:35 pm
content: Quote from: GreyWoolfe on May 27, 2019, 02:00:06 pmDamn, man, you STOLE that for $2! Buy the manual and MAKE space for it!-Pat

author: bitseeker
author_rank: Super Contributor
timestamp: May 28, 2019, 07:24:27 pm
content: Quote from: Enigma-man on May 27, 2019, 05:26:35 pmWow, lots of interesting things, E-man. That Vidar has an unusual looking enclosure, too.Looking forward to seeing the Panaplex train speedos, too.

author: bitseeker
author_rank: Super Contributor
timestamp: May 28, 2019, 07:25:30 pm
content: Quote from: Cubdriver on May 27, 2019, 08:22:35 pmNo kidding! Holy smokes.Well, Woolfie, if you really, really don't want it, neo probably does.

author: TERRA Operative
author_rank: Super Contributor
timestamp: May 29, 2019, 01:15:45 am
content: Quote from: Enigma-man on May 27, 2019, 05:26:35 pmThat's worth scanning to PDF for the archives for sure.

author: bob91343
author_rank: Super Contributor
timestamp: May 29, 2019, 03:26:25 am
content: This is my EI3000 voltmeter. Rated 0.01% on dc and 0.1% on ac, still works great.

author: tggzzz
author_rank: Super Contributor
timestamp: May 29, 2019, 08:44:57 am
content: Quote from: dexters_lab on October 09, 2015, 07:26:55 pmI'll raise you dekatrons plus 200-500V output plus finger accessible plus school equipment... With the EHT switched on, touching the GM socket's centre conductor with a finger causes it to count.No, you don't feel a shock since the output impedance is ~5Mohm

author: Enigma-man
author_rank: Regular Contributor
timestamp: May 30, 2019, 02:40:02 am
content: Wow ! Dekatrons. My favourite next to Nixies.I sure wish I could find a schematic for a low frequency counter because I have more than a dozen Dekatrons and haveno intention to make shitty Dekatron spinners out of therm.# bob91343... Very nice to see some rare pieces of equipment.

author: Enigma-man
author_rank: Regular Contributor
timestamp: May 30, 2019, 02:47:33 am
content: Vidar 500 Voltmeter revisited.I got the Vidar 500 fixed last night and here are two pix showing it measuring voltage compared to my Dana 5330and frequency compared to the HP 5340.The Vidar had several issues, but no collection of Germanium transistors, resistors and caps was going to defeat me.It works and that was my goal. The only one left to fix is the Systron Donner 1032 and it will be work again.

author: tggzzz
author_rank: Super Contributor
timestamp: May 30, 2019, 07:59:33 am
content: Quote from: Enigma-man on May 26, 2019, 05:44:26 pmThere are two types of Weston standard cell: saturated and unsaturated, with different voltages and tempco and lifetimes.Saturated cells are stable for decades (I have one from 1949), have a 40uV/C tempco, are fragile, so are only used in labs. Your image shows one.Unsaturated cells have lower tempco, are more robust, have a shorter lifetime, and were used in portable equipment.

author: bitseeker
author_rank: Super Contributor
timestamp: May 30, 2019, 05:10:21 pm
content: The Vidar lives!

author: schmitt trigger
author_rank: Super Contributor
timestamp: May 30, 2019, 05:34:54 pm
content: My ultimate idiot box: Nixies, Dekatron, Neon lamps, and a Magic eye. All counting in random sequences.All synchronized with beeps.A real mind-relaxing apparatus, very effective for dealing with headaches caused by stubborn people.

author: bitseeker
author_rank: Super Contributor
timestamp: May 30, 2019, 06:58:03 pm
content: Awesome. A video demo is requisite for this curiosity.

author: schmitt trigger
author_rank: Super Contributor
timestamp: May 30, 2019, 11:57:35 pm
content: I would love to share a video, but EEVBLOG doesn’t allow uploading videos?BTW; I have called this contraption “Der sinnlose Zähler”. The senseless counter. Although I ignore whether my German language skills are good enough and this name makes any sense.Or perhaps “The ultimate idiot box”, again in German.Perhaps some native German speakers may suggest a catchy name? That would be appreciated.

author: bitseeker
author_rank: Super Contributor
timestamp: May 31, 2019, 01:19:33 am
content: No problem. Video goes on YouTube. Link to video goes into EEVblog forum post.

author: greytop
author_rank: Newbie
timestamp: September 13, 2019, 09:45:50 am
content: I have just dug a Daystrom Schlumberger 1291 out, tried it 30+ years ago, functioned then. Must try it again

author: mikeinkcmo
author_rank: Newbie
timestamp: September 29, 2019, 12:21:10 pm
content: I've scrolled through all the pages and haven't seen an HP-312 selective volt meter.I also have a 5245M counter that I've had for quite a while.

author: Johnny10
author_rank: Frequent Contributor
timestamp: September 29, 2019, 01:45:54 pm
content: Now those are cool !

author: scopeman
author_rank: Frequent Contributor
timestamp: February 08, 2020, 09:08:49 pm
content: Quote from: mikeinkcmo on September 29, 2019, 12:21:10 pmWow I used to use a HP312 when I worked at Western Union in the late 70's before we replaced them with HP3586's.SamW3OHM

author: video99
author_rank: Newbie
timestamp: March 30, 2020, 10:01:46 pm
content: HelloA while back you mentioned a Fluke 8375A mnultimeter. I'm looking at one of these, there seems to be a power supply problem. I'm sure there should be a regulated output of about 9V from Q6 (the one with the heatsink) but I'm only seeing about 0.9V from there. I've checked pretty much every component on the PSU and replaced all bad ones but to no avail. I don't suppose you have a schematic for the PSU do you? I'm working blind and with the present crisis, finances are tight beyond belief so I can't really buy a manual for a unit which is more of a curiosity than a useful piece of test kit. I would just like to get it to run to show off the display if I can. At the m,oment the machine appears dead though the high voltage for the tubes is present.Thanks for any help if you can.All the best,Colincolin@video99.co.ukyoutube.com/video99couk

author: Cubdriver
author_rank: Unknown
timestamp: March 31, 2020, 07:48:46 am
content: Colin, I *think* I have a manual for an 8375A lurking about somewhere here (I have an 8375A in my to-be-looked-at pile, and am fairly certain that I got a hard copy manual for it). I'll try to find some time to dig for it in the next day or three, and offer what insight I can if it turns up.-Pat

author: Martian Tech
author_rank: Regular Contributor
timestamp: November 07, 2021, 06:31:24 am
content: 16 pages and no Heathkit?

author: bob91343
author_rank: Super Contributor
timestamp: November 07, 2021, 05:12:49 pm
content: EI 3000

author: Electro Fan
author_rank: Super Contributor
timestamp: November 08, 2021, 04:29:22 pm
content: Here is a HP 5327B displaying a 49,152,000 Hz signal from a Leo Bodnar GPSDO while taking a 10 MHz reference clock signal from a BG7TBL GPSDO. When I first got the 5327B several years ago it was missing the 8th tube and an IC so when I found a source I figured I'd go for some spares. The 5327B seems pretty accurate and it is just plain fun to look at.

author: Johnny10
author_rank: Frequent Contributor
timestamp: November 08, 2021, 05:03:05 pm
content: You've got to stock up just in case.

author: Electro Fan
author_rank: Super Contributor
timestamp: November 08, 2021, 07:05:36 pm
content: Quote from: Johnny10 on November 08, 2021, 05:03:05 pmThis is what I’m thinking.

author: Dave Wise
author_rank: Regular Contributor
timestamp: April 29, 2024, 03:10:55 pm
content: My Fluke 8100B 12000-count bench DMM with the very interesting Recirculating Remainder ADC. (Volts and ohms, no amps.) It's hard to get a good picture of the display due to multiplexing.

author: Dave Wise
author_rank: Regular Contributor
timestamp: April 29, 2024, 03:13:57 pm
content: One of my HP 740B DC Voltage Standard/Differential Voltmeters. On its side for troubleshooting. The Nixie tubes display the knob positions, they don't dynamically change with input voltage. So just an electronic version of the mechanical digit wheels on a Fluke differential voltmeter.

author: Dave Wise
author_rank: Regular Contributor
timestamp: April 29, 2024, 03:38:11 pm
content: My Monsanto model 2000 Digital Voltmeter. DC Volts only. Easy on the eyes 20000-count non-multiplexed display required many many RTL integrated circuits for counters and latches. As far as I can tell, this is Monsanto's only DVM ever. I never found any advertisements for it, just an oblique mention of "a digital voltmeter" in an article from Chemical Engineering News January 1966 edition... which I can't find anymore. Gift from the late noted Tektronix collector Stan Griffiths.It uses a single-slope converter with an electromechanical "Synchroverter" chopper. Communication across Guard is two pulse transformers with interesting signal timing. The automatic polarity switching is awkward and went through significant mods that appear to be from the factory, and it was still flawed - to measure a guarded negative voltage you had to manually connect GUARD to the IN terminal instead of the COMMON terminal. I fixed that by changing the circuit yet again. Other changes I made ended up inserting two microcontrollers to correct some timing glitches. It's kind of a Frankenstein but it works.

author: tggzzz
author_rank: Super Contributor
timestamp: April 29, 2024, 03:54:29 pm
content: Quote from: Dave Wise on April 29, 2024, 03:13:57 pmHow ... naff!The only reason I can think of for that is marketing run wild - possibly due to an (ignorant?) large customer wanting it.

author: Dave Wise
author_rank: Regular Contributor
timestamp: April 29, 2024, 06:36:48 pm
content: HP 740: It saves room on the front panel. As you can see, there is none to spare - they even put the input/output binding posts on cables.I wish they'd allowed you to turn the knobs from 9 to 0 instead of forcing you to crank all the way CCW. Dialing it up and down to follow a varying input is clunky, probably a reason differential voltmeters were discarded when DVMs came on the scene. But they can do things you can't do with a DVM and that's why I keep them.Monsanto 2000: I rediscovered the Monsanto article, actually only the abstract because the American Chemical Society wants $10 for the full article.https://doi.org/10.1021/cen-v044n004.p048Restoring it would not have been possible without the service manual which I was lucky to find.Fluke 8100: I don't know why they restricted it to 12000 counts, they could have done 16000 with virtually no changes.UPDATE: A bit more than no changes, because the primary DAC is weighted 4-4-2-1 instead of 8-4-2-1. The predecessor models counted to 11xxx... so 12 may have seemed like overkill.

author: agent_power
author_rank: Regular Contributor
timestamp: April 29, 2024, 08:52:47 pm
content: Cool thread. I have one of those Flukes (w/o that option with the needle) and this HEB Digimeter 702. There's some filtering in the window, the Nixies look a bit red.You'll see it in the repair section soon enough because it's got an intermittent fault.

author: tggzzz
author_rank: Super Contributor
timestamp: April 29, 2024, 09:19:24 pm
content: Does an early digital calculator count as "equipment"?No "=" key, not HP, approx 1971 i.e. pre-HP35, four circular ICs, six signal transformers, four PCBs with wiring harness interconnections.Very "early 70s" styling :)I

author: Dave Wise
author_rank: Regular Contributor
timestamp: April 30, 2024, 01:40:46 am
content: Oh you gave me a pain. In my 20's I had a complete working Wang 360SE system including a CP-1 card reader and one of the keyboards was a 360KT trig model. I gave it away.https://www.oldcalculatormuseum.com/wang360.html

author: BU508A
author_rank: Super Contributor
timestamp: April 30, 2024, 05:05:41 am
content: Quote from: tggzzz on April 29, 2024, 09:19:24 pmJust have a look at the very first posting in this thread.

author: tggzzz
author_rank: Super Contributor
timestamp: April 30, 2024, 10:13:48 am
content: Quote from: BU508A on April 30, 2024, 05:05:41 amTee hee. Only 8.5 years ago