hybridfree/eevblog-posts huggingface dataset:
Used mertrix with some defects is it worth getting? - Page 1
Forum section: electronics / testgear

author: broo0d
author_rank: Newbie
timestamp: July 29, 2015, 08:49:28 pm
content: Hi everyone,This my first post in this forum, I am a web developer/programmer who is starting to fall in love with electronics and physics.I've looked around for an oscilloscope locally, all i find is a new highly price oscilloscopes.The only used ones i found is a metrix ox 8050 60MHZ digital/ 40 MHZ analog for about 105$, and another metrix ox 8050 100MHZ/60MHZ (80$). more specifications is in the urlhttp://www.farnell.com/datasheets/20712.pdfDid not find a service manual or any manual mentioning that units.First thing i will using it for is to tune my car audio, so FFT and harmonics functions will come handy, then maybe later do some arduino stuff.It is sold as is with no warranty or refund, the only option is to run it and see by yourself.So the first one (metrix ox8050 60MHZ/40MHZ 105$) had some missing knobs and dents. when playing with vertical v/div and put it to minimum (not sure) there is a wave showing on the screeni don't know if it is because being next to an electrical stuff. there is no probes to do any testing, i have to buy probes to test this unit.The second one (metrix ox8050 100MHZ/60MHZ 80$) looks clean outside. but the screen is out of focus and the controls didn't do anything, same thing with intensity. they have probes, but i didn't do any much further test. other buttons seems to works.So the question here is should i get one of these and try to fix it either by myself or hand it to a repair shop. Is it easy fix and worth the hassle.These two are the only thing i could found locally.The only other place i could find some good oscilloscopes with a little bit cheaper shipping prices than ebay is a chinese website called taobao.most likely no one ever heard about it. it like en ebay alternative to Chinese people.I looked around and found that they have an imported and fixed and calibrated,two years warranty claimed oscilloscopes. for example Hitachi V1560 100MHZ for 125$, there is a cheaper ones but shipping price to my country is about 90$What do you think? get of the local ones and fix it, buy from china, or neither.TL;DRThere is two used oscilloscopes locally, one with blur screen and intensity knob didn't work, the other one showing wave form with no probes connected.Are they worth getting and fixing? another alternative is buy from china an imported (japanese hitachi for example) tested and calibrated oscilloscope, they cost double price of the previous two.
Fluke/Phillips PM5193 Function Generator - Page 1
Forum section: electronics / testgear

author: sirkha
author_rank: Newbie
timestamp: August 02, 2015, 10:25:08 am
content: I scored one of these on Ebay the other day, and it arrived today. I was happy to get it to work and to do some fun things. The only other post on this equipment seems to talk a lot about the PM5139, but not the PM5193.Here are some links to what I have been able to do with the function generator so far:A quick linear function sweep:https://vine.co/v/eHADrnezqDY50% AM Modulation:https://www.flickr.com/photos/sirkha/20196301856/in/datetaken/My first impressions are that it is fairly intuitive to use, but that the fan is very loud and that there is a funny smell coming out the back end. The light will blink at you need to enter a value to get a certain function to work, and the controls are laid out pretty well. It looks like it can store up to 8 settings, but I am not sure if those will last through a power cycle. Reading the information on it, it does DDS up to 2 or so MHz and then switches to a PLL with appropriate shaping circuitry. Seems to be pretty standard 80s style design with a microprocessor and a whole lot of DIP chips.Manuals:http://www.ko4bb.com/manuals/index.php?dir=PhilipsI am planning on opening it up to see what I can do about the fan and give it a bit of a cleaning. Is there anything that anyone would like to see on the inside, or functions that they would like to see working?-- John

author: pascal_sweden
author_rank: Super Contributor
timestamp: August 02, 2015, 10:33:55 am
content: Maybe you can improve the lighting conditions a bit in your work shop, so that we can see the actual equipment in its full glory
Rebranded Function/Pulse Generators - Page 1
Forum section: electronics / testgear

author: sirkha
author_rank: Newbie
timestamp: July 27, 2015, 05:25:17 pm
content: Hi, looking through ebay, I have found a couple of these CA1641/CA1642/CA1641p/CA1642p function generators, and was wondering if anyone knew anything about them. They seem to be going for pretty cheap, but looking for more information on them, they seem a bit like a Chinese attempt at market undercutting.http://www.ebay.com/itm/20MHz-FUNCTION-GENERATOR-COUNTER-with-Power-Output-/300539617363http://www.smtmax.com/detail.php?id=84http://www.ebay.com/itm/-/221391196045http://www.madelltech.com/m1-8.htmlMost of my suspicions come from two different brands with nearly identical model numbers and specs, and the phrase, "Sleek, artistic cabinet design."I'd probably go with the CA1642P-20, since it seems to have a USB interface. Any thoughts?

author: Andy Watson
author_rank: Super Contributor
timestamp: July 27, 2015, 05:44:07 pm
content: The Madell CS1640-20 appears to be rebadged as a Digimess FG200 (or vice-verci) - which I have to give a big thumbs down. The frequency can only be set in random increments - I suspect mains signal is interfering with the oscillator due to poor shielding/construction. The buttons are not debounced properly which makes for interesting selection of functions! I was going to give it away but the poor construction, particularly with regard to the mains wiring, make it a bit of liability.

author: pascal_sweden
author_rank: Super Contributor
timestamp: July 27, 2015, 05:57:28 pm
content: For that money you better buy a Siglent SDG1025 or spend little more for a Rigol DG1032Z.

author: rickv14623
author_rank: Frequent Contributor
timestamp: July 27, 2015, 06:47:28 pm
content: I have to agree with Pascal. If you are in the US a good source with support would behttp://www.saelig.com/product/M00110003.htm

author: sirkha
author_rank: Newbie
timestamp: July 27, 2015, 07:31:36 pm
content: Okay, good to hear that my suspicions were not unreasonable. Thanks!
Rigol DG1032Z teardowns (China review) - Page 1
Forum section: electronics / testgear

author: susu
author_rank: Newbie
timestamp: December 28, 2013, 02:43:10 am
content: I saw some of the in side pictures Rigol DG1032Z herehttp://forum.eepw.com.cn/thread/244917/1Share with everyoneAny worthwhile on this product is beneficial for me. Thanks you

author: Eric.Zeng
author_rank: Newbie
timestamp: July 26, 2015, 04:47:26 am
content: It looks beautiful!

author: pascal_sweden
author_rank: Super Contributor
timestamp: July 26, 2015, 12:16:20 pm
content: And it has a JTAG interface to possibly turn it into a DG1062Z
Voltage Spikes from multimeter  - Page 1
Forum section: electronics / testgear

author: fivefish
author_rank: Frequent Contributor
timestamp: July 25, 2015, 03:34:59 am
content: So I'm breadboarding a PSU, and noticed these regular interval spikes while I'm trying to measure ripple.There's a Rigol 1054Z scope connected at PSU outputs, along with BK Precision 5492 bench multimeter measuring volts output.I saw an episode on Dave's video where his fluorescent/office lights were the culprit on some spikes on his scope. So I tried turning off my desk lamp and other lights and the spikes are still there.On a hunch, I removed the multimeter from the equation, so only the scope is connected to the PSU breadboard.Voila! The spikes disappeared! Granted, these spikes are very tiny and very short duration, but it did threw me off. I thought it was the PSU design causing it.Anyways, just putting this out there. Learned something new today with my BK multimeter. Do you guys encountered something similar with your test equipment?
Bench layout, meters and heat - Page 1
Forum section: electronics / testgear

author: alanambrose
author_rank: Frequent Contributor
timestamp: July 29, 2015, 04:14:28 pm
content: Hi,Does anyone have a view - should I keep my more sensitive equipment (6.5 digit meters, 12 digit counters etc) separated thermally on the bench (rather than stacked one on top of the other)? And if I should - how big a deal is this / how much trouble should I take?TIA, Alan

author: G0HZU
author_rank: Super Contributor
timestamp: July 29, 2015, 04:29:45 pm
content: I've always followed the basic guidelines I was taught when I first started working in an RF lab. Keep the bench uncluttered and keep sensitive items like power meters, counters and bench DMMs away from items of test gear that run warm.Although I don't use it much, my Fluke 45 bench DMM sits on its own mini shelf and my Anritsu power meter sits on its own shelf on its own and neither item has anything running below it that could cause a temperature gradient.I rarely use a counter but when I do I usually use an external (fast warmup) OCXO reference so I try and keep the external reference box away from other (warm or hot) test gear. So the location of the counter itself becomes less critical.I'm quite happy to stack RF sig gens on top of each other as long as they have a decent internal OCXO and a decent ALC levelling system.Modern test gear is fairly tolerant of changes in ambient temperature but I think it's just good practice to keep certain items of test gear in a location that avoids unnecessary temperature gradients.
Neon displays in HP5275A timer - Page 1
Forum section: electronics / testgear

author: artag
author_rank: Super Contributor
timestamp: July 24, 2015, 11:00:31 pm
content: I've started restoring an HP5257A interval timer from 1965. In it's in pretty good condition, though it doesn't actually work (yet). So far I've found a couple of big o/c caps in the power supply.I'm intruiged by the numeric displays, though. They're the type with 10 neons, each illuminating a window from 0 to 9. Nice and old but not insane. What's amazing is the conversion from the 4-bit binary counters (transistor flipflops) to 1-of-10 neons.This consists of 8 neons (two per flipflop, one on Q and one on /Q) and 18 LDRs. The LDRs are arranged near the neons in a particular arrangement such that certain combinations are illuminated by specific neons. And if 3 LDRs are illuminated, one of the front panel neons is lit in turn.The binary count is slightly peculiar, running 0,1,2,3,6,7,c,d,e,f - this doesn't really matter as long as the decoding and carry work accordingly, and means that digit 0 is illuminated when bits 0, 1 and 3 are off, digit 1 when bit 0 is on, bits 1 and 3 off, digit 4 when bit 2 is on, bits 0 and 3 off, etc.I'm not sure what I expected - perhaps a 10 point ring counter, illuminating the front panel neons like a decatron. Or a diode array. But a product-of-sums combinatorial logic array built from lamps and light dependent resistors ? Wow.
Peak DCA75 Pro photos - Page 1
Forum section: electronics / testgear

author: dadler
author_rank: Unknown
timestamp: March 06, 2015, 04:37:17 am
content: I took some photos of my Peak DCA95 Pro. This is an incredibly useful device for identifying semiconductors--I particularly love the curve tracing functionality.

author: SteveyG
author_rank: Unknown
timestamp: April 05, 2015, 12:04:19 am
content: I agree, a great unit to have around! Review and teardown here:

author: necroscope
author_rank: Regular Contributor
timestamp: April 05, 2015, 12:50:43 am
content: +1^ Top bit of kit....I use mine all the time for repairs, also a handy tip for an unrecognised voltage regulator is to test a recognised regulator of the same value and run the curve tracer feature then swap out pin for pin for the unrecognised regulator and run the traces again and you can compare the two devices on the curve tracer...

author: dadler
author_rank: Unknown
timestamp: April 05, 2015, 02:56:34 am
content: Quote from: SteveyG on April 05, 2015, 12:04:19 amThanks for the review! You probably deserve your own topic, my cheesy pictures aren't much compared to your video review.I agree the device could use a tilting bail. I put mine on this small "iZel" stand that I bought on Amazon:https://www.dropbox.com/sc/ndg5wpj6kru1y7m/AAD-xePp5sfBUrcwiyAhmAdjahttps://www.dropbox.com/sc/1opx30cen97xhuh/AAByD99cg-5wQb6rsXH5UctDa

author: Michaela Joy
author_rank: Contributor
timestamp: July 23, 2015, 11:58:19 pm
content: I just purchased one. Am awaiting delivery.

author: HighVoltage
author_rank: Super Contributor
timestamp: July 24, 2015, 08:07:52 am
content: I got mine at the end of 2014 and used it a lot since then and still works perfectly.This is a highly recommended test gear, especially in combination with the software.

author: Hydrawerk
author_rank: Super Contributor
timestamp: July 24, 2015, 09:44:35 pm
content: Nice instrument, but hard to repair. I prefer that Karl-Heinz Kübbeler DIY version with open source hardware and software.https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/

author: dadler
author_rank: Unknown
timestamp: July 24, 2015, 10:34:41 pm
content: Quote from: Hydrawerk on July 24, 2015, 09:44:35 pmNot the same device at all. This is a curve tracer with PC software.
[TIP] Firewire based instruments and Win7 / Win8 - Page 1
Forum section: electronics / testgear

author: free_electron
author_rank: Super Contributor
timestamp: June 12, 2014, 05:36:14 pm
content: There exists test equipment that uses firewire as a communications interface. Some internally, some externally. ( The Agilent 1680/1690 family of Logic analyzers for example ).The problem starts when you want to use such machines with Windows 7/8 or want to upgrade the internal OS.The same problem exists with certain video camera's and audio equipment like MOTU )Microsoft altered the fire-wire driver in Win7. The new universal driver for OHCI compliant cards does no longer detect devices attempting to initiate TCP/IP transport over firewire.So, when you plug in such a machine they are not detected .Windows 7 solutionThe problem is easily solved by going in the Device manager and selecting the firewire cardClick "Update driver software ..."Click "Browse my computer for driver software"Click "let me pick from a list of device driver on my computer ..." and Check the box before “Show compatible hardware”.Select the "1394 OHCI Compliant Host Controller (Legacy)"and click next to update the driver.Windows 8 SolutionFrom a windows 7 machine get the following files :c:\windows\inf\1394.infc:\windows\inf\1394.pnfc:\windows\system32\drivers\1394bus.sysc:\windows\system32\drivers\1394ohci.sysc:\windows\system32\drivers\ohci1394.sysyou may need to disable the driver signing to be able to load these.

author: Graz
author_rank: Contributor
timestamp: July 24, 2015, 11:24:17 pm
content: I know this post is ancient and I apologize for the necromancy, but I just wanted to say thanks for the tip. I have a 1692A that I picked up for a "bargain" and it's been sitting on a shelf for months because I couldn't get it to work. Figured it wasn't such a bargain after all. I searched everywhere for a solution. Finally found this post. Now it's working perfectly.Thanks, man! That's a great tip.
Tektronix DSA 602 - Page 1
Forum section: electronics / testgear

author: Johnny10
author_rank: Frequent Contributor
timestamp: July 24, 2015, 01:28:58 am
content: What more modern oscilloscope is comparable to Tektronix DSA602 or any thoughts on whether to purchase this unit.

author: miguelvp
author_rank: Super Contributor
timestamp: July 24, 2015, 02:51:01 am
content: According to:http://w140.com/tekwiki/wiki/DSA600You can gang up the four DSA 602 digitizers (500Msps each) for up to 2Gsps on a single channel I would assume.But it did accept 11000-series plug-ins and one of those claims 3GHzhttp://w140.com/tekwiki/wiki/11A81The 4 channel one is 300MHzhttp://w140.com/tekwiki/wiki/11A34But I don't know if you could use those plug-ins to the fullest.But a 4Gsps 4 channel 350MHz scope candidate would be a Rigol DS4034http://www.tequipment.net/RigolDS4034.htmlBut if you want a better brand I'll look atHP/Agilent/Keysight DSOX3034 or MSOX3034 might do but at double the price.Or maybe the DSO7034 or MSO7034 series with more memory depth and more $$$.But I guess it all depends what bandwidth, number of channels etc you have in mind.

author: JoeB83
author_rank: Regular Contributor
timestamp: July 24, 2015, 03:29:06 am
content: Quote from: Johnny10 on July 24, 2015, 01:28:58 amI don't mean to sound rude, but this is a very generic question. In what ways are you looking for something comparable? What do you plan on using it for? How much is it being sold for?

author: Johnny10
author_rank: Frequent Contributor
timestamp: July 24, 2015, 01:12:32 pm
content: I don't think you are rude.My question was actually related to my dead 11402A.Had the 11402A only about a week and after playing with the unit I started to like it.Then it came up with errors and a jumbled display!These scopes are so inexpensive now that I wondered if moving to the DSA 620Since I already have a plugin... made any sense?Color Display, FFT, more analysis.But is it all just a waste of money?Are newer scopes in the 400-600 range that much better?Also I found very little information n repairing these scopes.Everything it seems was an exchange of boards.I like old scopes, don't mind the size. Already have 7854 which I also have gotten used to using.
Aid Needed in Troubleshooting a Power Designs 3650S Power Supply - Page 1
Forum section: electronics / testgear

author: DC912
author_rank: Contributor
timestamp: July 29, 2015, 03:06:34 am
content: I picked up a Power Designs 3650s power supply in decent cosmetic condition, but unknown operating condition. Turns out it needs some electronic repairs.The symptoms are: The DC+ at the output is always about 1/2 of the voltage indicated on the panel meter (in other words, the voltage at the output is always about 1/2 of the indicated panel meter voltage when increasing from 1 to 36v), and the DC- at the output always hovers near zero.The current limiiter appears to function. The transformers check out okay. There are no signs of physical damage or prior repairs inside. I checked the electrolytics in circuit with an LCR meter and they appear to be okay too.The schematic is on the ko4bb site. Any thoughts on specific components or circuits to check given these symptoms would be appreciated. Thanks.

author: eas
author_rank: Frequent Contributor
timestamp: July 29, 2015, 06:11:44 pm
content: The 3650S is a floating single output supply. Are you measuring the DC+ to ground, or to DC-?

author: electr_peter
author_rank: Unknown
timestamp: July 29, 2015, 09:38:59 pm
content: Quote from: eas on July 29, 2015, 06:11:44 pmI guessDC912measured DC voltage to ground, but not between DC+ and DC- terminals. This statement seems to suggest it:Quote from: DC912 on July 29, 2015, 03:06:34 amMeasure voltage between DC+ and DC-. Voltage readings between [DC+ and Ground] or [DC- and Ground] are meaningless as this is a floating supply.

author: DC912
author_rank: Contributor
timestamp: July 30, 2015, 12:10:54 am
content: Thanks for the replies. Yes, I was measuring between ground and DC+/DC- because I presumed, incorrectly, the ground was common. It never occured to me that this was a floating supply! Thanks again. Dave.
Rigol 1054z vs 2072a - Page 1
Forum section: electronics / testgear

author: onrainbow
author_rank: Newbie
timestamp: July 12, 2015, 03:59:58 pm
content: Is there any reason to buy the 2072a instead of 1054z nowadays? It just seem to me that 1054z has two extra channels (which is certainly helpful) with half the price. Can you, for example, hack the 2072a to 300Mhz bandwidth?

author: JackP
author_rank: Regular Contributor
timestamp: July 12, 2015, 04:10:17 pm
content: Yep, it can be hacked. Plus, you get the waveform record feature with the big knob

author: Muxr
author_rank: Super Contributor
timestamp: July 12, 2015, 04:30:39 pm
content: Quote from: onrainbow on July 12, 2015, 03:59:58 pmThey can both be hacked. 2072A can be unlocked to 300Mhz and also has a 2 Gs/s. It has a bigger screen as well. But 1054z has more channels.1054z for the price is a better deal but there are good reasons to go for 2072A as well.

author: f1rmb
author_rank: Regular Contributor
timestamp: July 12, 2015, 07:45:46 pm
content: Or get both ;-)

author: dadler
author_rank: Unknown
timestamp: July 13, 2015, 08:37:37 pm
content: I have both. Use the DS2000 when I want bigger screen/ability to remove side menus, higher bandwidth, CAN decoding. Use DS1054z when I want 4 channels, also use it as a cheaper/portable scope. I sometimes use them together with the external trigger feature.I find myself using the 2000 more often due to the larger screen.

author: f1rmb
author_rank: Regular Contributor
timestamp: July 13, 2015, 09:16:23 pm
content: Same here, I use my 2000A more often due to larger screen, but when I need more than 2 channels, I use my 1054z. And sometimes both scopes at the same time.Cheers.---Daniel

author: tautech
author_rank: Super Contributor
timestamp: July 13, 2015, 11:43:00 pm
content: Quote from: onrainbow on July 12, 2015, 03:59:58 pmAt least double the sampling speed.

author: leafi
author_rank: Regular Contributor
timestamp: July 23, 2015, 04:25:08 am
content: I have the 2072 and the 1074zs and my company just purchased a 1054z. I think the UI feels faster on the 2072 when its at longer time scales such as 100ms and such. The 1054 and 1074 screen feels confined compared to the 2072 as well. Everything seems crampt where the 2072 has more room. The 2072 is much much heavier too so if you plan on carrying something with you the 2072 is not as good on that front.
Finding Age Of Tektronix Equipment - Page 1
Forum section: electronics / testgear

author: George_Race
author_rank: Regular Contributor
timestamp: July 27, 2015, 12:26:43 am
content: I am trying to determine the year of manufacture of several pieces of Tektronix Test Equipment.Is there a year grouping, maybe by serial number, or a particular place one can look inside and find the production date of any of the Tektronix test gear?Does not help to look in the catalogs, as the same gear and specifications may appear for many years in a row, just the price seems to go up as it become a new year!Also I have heard that some of the Tektronix gear was manufactured in other countries, is there a way to tell where from? As well, some is made by other manufacturers, how do you find out who made it?George

author: helius
author_rank: Super Contributor
timestamp: July 27, 2015, 01:01:18 am
content: Using the catalogs is the best approach, since even though an instrument may appear in several catalogs, there is always one year it appears first. Sometimes people have already compiled this information for you:http://www.ebay.com/gds/A-Guide-to-Tektronix-2000-Series-Oscilloscopes-/10000000001406477/g.htmlAdditionally there is usually a copyright date on the stencil artwork.The country of origin is part of the serial number, as described here:http://www.tek.com/export_codes

author: Electro Fan
author_rank: Super Contributor
timestamp: July 27, 2015, 02:34:11 am
content: This is a pretty good resource:http://www.barrytech.com/tektronix/tek.htmlIt doesn't give the age of all models but for some equipment it helps home-in on roughly the years the model was in production - plus it has some specs and occasionally some historical pricing info.Tektronix has some info on some models, for example:http://www.tek.com/support/faqs/7000-series-oscilloscopes-faqAnother good site:http://w140.com/tekwiki/wiki/Main_Page

author: George_Race
author_rank: Regular Contributor
timestamp: July 27, 2015, 12:01:45 pm
content: Thanks, lots of clues to follow up on.

author: amyk
author_rank: Super Contributor
timestamp: July 27, 2015, 01:45:45 pm
content: Don't forget the simplest way: check the datecodes on the components.

author: owiecc
author_rank: Frequent Contributor
timestamp: July 27, 2015, 01:51:13 pm
content: Exactly, check few ICs and you will find date codes in YYWW format (year, week no.). The newest chip will give you a good estimate of production date.

author: edavid
author_rank: Super Contributor
timestamp: July 27, 2015, 03:37:24 pm
content: Quote from: George_Race on July 27, 2015, 12:26:43 amNo.QuoteSerial number prefix, e.g. B = BeavertonQuoteFind the OEM model that looks the same, or ask a former Tektronix employee.
Who makes the Keithley 3390  - Page 1
Forum section: electronics / testgear

author: yanodamano
author_rank: Newbie
timestamp: July 21, 2015, 11:29:49 am
content: Hi, I'm looking for a good quality ARB and Keithley make a nice one the 3390.However when I look around there is a BNC 645 and Picotest G5100A that look exactly the same!Does anyone know who actually produces this unit and if its any good?Thanks

author: yanodamano
author_rank: Newbie
timestamp: July 22, 2015, 09:34:10 am
content: OK I found out some more! Its supplied to Keithley by Picotest! After doing some more searching I found the same unit supplied by a company in China called Array Electronics. I'm not sure if its an Array Electronics design or Picotest but they are selling them.So it seems there are very few of the big names making waveform generators, just Agilent and Tek (but some of theirs look a bit...well lets say cheap looking).I've been bitten by cheap test equipment before, so call me a snob but its looking like an Agilent....and a lot of money!

author: Hydrawerk
author_rank: Super Contributor
timestamp: July 22, 2015, 07:44:45 pm
content: There are also some generators made by Hameg.http://www.hameg.com/149.0.html?L=0
Acopian 10KV High Voltage Power Supply Teardown and Test - Page 1
Forum section: electronics / testgear

author: sburrell
author_rank: Newbie
timestamp: July 22, 2015, 08:32:05 pm
content: On a swap I ended up with with a HV Supply and did some basic tests and teardown (As much as taking off the covers) prior to turn on since its condition was unknown. If anyone has a source for the connector used in these I'd like find one. If I had to guess I'd say it would be a GES S series but I can't be entirely sure. Maybe someone here knows?DISCLAIMER - HIGH VOLTAGE SUPPLIES CAN KILL YOUFull Writeup and Video avail athttp://www.shaneburrell.com/?p=1089
Calibrating Tektronix TAS485 - Page 1
Forum section: electronics / testgear

author: Mark11
author_rank: Newbie
timestamp: July 19, 2015, 09:07:24 am
content: I am trying to calibrate my old Tektronix TAS 485 oscilloscope as described in Instruction Manual -Adjustment Procedure starting from page 7-1. Unfortunately I am stuck on Factory Horizontal Call(page 7-7 of Instruction Manual) step 4.Instead of initiation of the calibration routine I got the message ''See manual to enable factory cal''.Software version in TAS 485 is V2.5 94/09/02Any idea what am I doing wrong?Thanks!Mark

author: JoeB83
author_rank: Regular Contributor
timestamp: July 19, 2015, 09:03:00 pm
content: Dumb question-you've completed the steps prior to this one, correct?

author: Mark11
author_rank: Newbie
timestamp: July 22, 2015, 08:16:48 am
content: Problem solved.The solution (not written in my copy of the manual):Before starting of the calibration procedure remove the jumperon the NVRAM board (Q9A-1220-02). The jumper is located in theright lower corner of the board labeled CAL.Thanks for the reading.Mark
Reflective tachometer recommendation? - Page 1
Forum section: electronics / testgear

author: Circlotron
author_rank: Super Contributor
timestamp: July 19, 2015, 09:29:15 am
content: Thinking of buying a digital reflective tachometer. Spend no more than say USD$50. 0.1% accuracy preferred. Probably no higher than 5000 rpm needed. What do people recommend.

author: robrenz
author_rank: Super Contributor
timestamp: July 19, 2015, 05:20:17 pm
content: I just got this one and it works excellent. it is laser and mechanical input. it was free shipping in the US this model is available from many vendors at many prices. I give itLink here

author: tautech
author_rank: Super Contributor
timestamp: July 19, 2015, 09:24:36 pm
content: Quote from: robrenz on July 19, 2015, 05:20:17 pmI've got an old unit but very similar but with white light and photodiode optical sense.It will sense just fine on white tape but reflective tape is better.Do Laser types need a reflective tape target to work?

author: robrenz
author_rank: Super Contributor
timestamp: July 21, 2015, 02:48:01 am
content: It came with reflective tape and it works fine with that but I didn't try it with just white tape.EDIT: Works on white tape also.

author: Circlotron
author_rank: Super Contributor
timestamp: July 21, 2015, 03:11:28 am
content: Just had an afterthought.Are there any cheapo digital tachos available that have an analogue DC output that you could connect to a chart recorder, data logger or slow scanning scope?
HP 3312A - Page 1
Forum section: electronics / testgear

author: Aztlanpz
author_rank: Regular Contributor
timestamp: July 21, 2015, 08:00:27 pm
content: Up to what frequency is the HP 3312A is rated to produce a square wave with low distortion?Aztlan

author: barry14
author_rank: Regular Contributor
timestamp: July 21, 2015, 09:48:46 pm
content: The HP 3312A Function Generator will generate square waves up to its maximum frequency of 13 MHz. The quality of the waveform is limited by the specified rise and fall times of 20 nanoseconds.

author: wn1fju
author_rank: Frequent Contributor
timestamp: July 21, 2015, 10:03:21 pm
content: In the classical sense, "low distortion" and "square wave" do not belong in the same sentence! A square wave has lots of harmonics (infinite in the purely theoretical sense) and by definition has high distortion (approaching 50%). If you mean by "low distortion," namely what "looks good on a scope," then, as the previous post says, it is limited by the 20 ns rise and fall times which will turn a high frequency square wave into a trapezoidal waveform.
TCP202 Repair - Page 1
Forum section: electronics / testgear

author: robert_
author_rank: Regular Contributor
timestamp: July 21, 2015, 08:53:21 pm
content: I recently found a TCP202 current probe that previously had some sort of rather loud, fairly high energy accident. The ferrite core is crumbled to pieces and even a part of the metal shielding is blown off!As for the other end of it, it doesnt look too good either, the top board was quite blackened. After a good cleaning, at least this looks manageable, there are 2 SMT R (or C) missing, a few traces damaged and some more reistors are open. Parts are standard as far as ive seen (LM1458 and OP27 and a handfull of 3pin SOT23s) so i guess its repairable. I do have access to a working 202 to determine the missing component values, and eventually to compare measurements.That is, if i can get the actual current sensor module replaced. I guess asking Tek for a spare part is wasted time, considering their craptastic support and the pricing im used to.My idea was that maybe some of the older probes (like P6302, which seems to be fairly affordable without its amplifier) might have the same transducer? Specs are quite similar, and they look very similar mechanically.Any ideas about this?Any good photos of P6302 etc. innards, especially the transducer and its connections?

author: edavid
author_rank: Super Contributor
timestamp: July 21, 2015, 09:32:27 pm
content: The probe innards do look the same, but the tricky part would be the calibration. If you find a working P6302/A6302, why not leave it intact and buy an AM503? They are not expensive (especially if you hack up your own power supply), and that way you can use it with any scope.

author: robert_
author_rank: Regular Contributor
timestamp: July 21, 2015, 09:50:17 pm
content: Quote from: edavid on July 21, 2015, 09:32:27 pmI did think about the AM503 but i dont think its too great. Id prefer setting the scale factor right at the scope (and not accidentally set one of them wrongly and then wonder why im measuring crap) and not having a large extra box standing around. Its not too cheap either, the P/A6203 is around 200-300 for a "working" one, AM503 is around 300, plus TM501 (or maybe selfmade) for another 100-200. For that price, i can get a used, working TCP202 (ebay currently has a few for around 700-800).Tekprobe interface isnt great but at least there are quite a few scopes supporting it, also newer Tek (VPI) and Agilent series would work too with an (not cheap, but i have other Tekprobe active probes too) adaptor.

author: edavid
author_rank: Super Contributor
timestamp: July 21, 2015, 09:53:13 pm
content: Well, they are much cheaper in the US:http://www.ebay.com/itm/TEKTRONIX-AM-503-CURRENT-PROBE-AMPLIFIER-/391187807937
HP 4155B Semiconductor Parameter Analyzer - SMU - Need Master Disk - Page 1
Forum section: electronics / testgear

author: Jay_Diddy_B
author_rank: Super Contributor
timestamp: July 19, 2015, 01:17:08 am
content: Hi group,I am looking for the Master Disk for a HP 4155B Semiconductor Parameter Analyzer. When I got the equipment it was displaying garbage on the LCD screen. I reseated one of the display connectors and now it shows:Can anybody supply an image of the disk?Thank you for your help.Jay_Diddy_B

author: photon
author_rank: Frequent Contributor
timestamp: July 19, 2015, 07:21:04 am
content: Hi Jay_Diddy_B,I am not sure this is what you need. Just in case you haven't looked at it yet...http://www.keysight.com/main/software.jspx?ckey=213376&lc=eng&cc=US&nid=-11143.0.00&id=213376

author: Jay_Diddy_B
author_rank: Super Contributor
timestamp: July 19, 2015, 02:35:21 pm
content: Quote from: photon on July 19, 2015, 07:21:04 amThank you very much. I hadn't realized that the same firmware is used on the B and C models.I downloaded the zipfile from Keysight. Copied the files onto four floppies. Installed the firmware into the machine and now I have a working unit.Here is the configuration screen after installing the firmware:Here is an IV plot of a green LED:I will have to work how to make the test fixtures.Thank you again!!Regards,Jay_Diddy_B
Tektronix 2710 spectrum analyzer - firmware, flatness - Page 1
Forum section: electronics / testgear

author: kuba
author_rank: Newbie
timestamp: July 16, 2015, 10:25:34 am
content: Hello,It's my first post here so hello to everyone and thanks for such a great forum !I have a Tektronix 2710 spectrum analyzer and recently it suffered a strange failure which resulted in the lack of flatness oin the measurement band. According to the specs flatness is +/- 1,5dB in 10kHz-1,8GHz range. In my case it was hardly in +/-5dB (as seen in the picture). After hours of checking it turned out that the level of the 1st Local Oscilator was too low at the input of the 1st converter (2,11 GHz IF) - a MESFET transistor was dead in the buffer amplifier of the 1st LO and the ALC circuit was not able to work properly...Now the 2710 has a flatness within specs (+/-1,5dB) but I would be grateful if someone would post a picture of his Tek 2710 and its flatness in the measurement band .And a second question to tek2710 owners - My SA has a firmware dated: 01.15.90 - is there any newer firmware version ?Thanks

author: Fraser
author_rank: Super Contributor
timestamp: July 16, 2015, 11:08:21 am
content: @Kuba,Where are you located please ?I have a Tektronix 2710 Spectrum analyser that I will likely be selling as its power supply has a fault. If you are interested in a spare parts donor, let me know and we will see if we can agree a value. The unit is in excellent physival condition but blew its prergulator and that took out the inverter transistors. I intended to repair it but its been years since I looked at it.I am in the UK.Best WishesAurora

author: Electro Fan
author_rank: Super Contributor
timestamp: July 16, 2015, 10:27:12 pm
content: How was the flatness test done? (What process with what equipment?)

author: kuba
author_rank: Newbie
timestamp: July 16, 2015, 11:07:04 pm
content: The result seen in the picture was achieved with the builtin tracking generator but before using the TG two tests were done:1 The flatness was checked with SMIQ03B with valid calibration cert. and compared with the flatness test using TG - it is nearly the same2. The cable and N-SMA adapters were also checked using SMIQ03 and another SAI am using the built in TG with default cal values (no cal) just because of the ease of the test setup ... , the results are nearly te same. To use the calibrated generator for the flatness test and tuning I would have to synchronize its sweep with the sweep of the SA.

author: Fraser
author_rank: Super Contributor
timestamp: July 18, 2015, 11:43:46 pm
content: Thanks to those who showed an interest in my faulty 2710.It sold this evening so is no longer available. I think someone got a good deal but I am pleased it went to a good home.Aurora
8590b tracking problem - Page 1
Forum section: electronics / testgear

author: drforbin
author_rank: Regular Contributor
timestamp: July 17, 2015, 10:33:09 pm
content: Hi all. I just rescued a 8590b from the trash. It had a bad RES BW filter on A13 100Khz which I repaired.But it seems the tracking feature is operating in correctly, or maybe not!That's what I'm here to ask. When I place a marker near a signal and hit signal track it will track but it finds the largest signal it can rather than tracking the signal the marker is on.This is contrary to the behavior which is expected according to the manual. This function seems to be completely firmware (digital software) derived. So my question is,is this the proper behavior, and if not what should I look for in the way of faults?Thank you.Drforbin.

author: Electro Fan
author_rank: Super Contributor
timestamp: July 18, 2015, 06:57:34 pm
content: I don't know about a 8590b but on a HP856XE series the marker can be manually moved using Delta Markers to help measure differences or it can be moved with a Peak Search button to find the current largest Peak or the Next largest Peak. There might be a way to track a particular signal as the signal moves on the display but I'm not familiar with that feature.Update - found this in the 856XE manual:SIG TRK ON OFF / MKR: Switches the signal tracking function on and off. When it is on, it keeps the active marker on the peak of the signal where it was initially placed and keeps the center frequency at the marker value. A K appears on the left side of the display to indicate this function is active.- I think this means it finds an initial peak and then keeps the center frequency at the frequency at which it found the initial peak, but if the signal moves the center frequency will stay where it has been placed - so it's really tracking (monitoring) the frequency that was initially found but the signal itself could move elsewhere (potentially off the display depending on your span setting and of course the bandwidth of the SA)- another potentially interesting feature is the Sweep control; if you change it from Continuous to Single (kind of like an oscilloscope) you can then use the Marker and Peak Search controls to locate and measure signals while they are fixed on the display
Has anyone hacked a Hakko FM-2024 control (C1492)? - Page 1
Forum section: electronics / testgear

author: Gregg
author_rank: Super Contributor
timestamp: July 17, 2015, 05:13:02 am
content: I recently purchased a Hakko FM-2024 desoldering handle to go with my FM-203 Station. I did not purchase the control box (C1492) because I intend to use a small dual diaphragm vacuum pump I already have. I ohmed out the FM-2024 and found the vacuum actuation switch merely bypasses an 850 ohm resistor that normally is in series with the LED pilot light; in other words, when the unit is operating without the control box and I press the trigger, the LED gets brighter.My plan is to put a solenoid valve in the suction line with a disposable ceramic air line filter to keep crud out of the solenoid valve. The electrical connections seem to be standard 8 pin DIN, somebody please correct me if I’m wrong. I plan on making a breakout cable to measure the voltage change when the switch is activated but am awaiting the DIN connectors.I’ve searched this and other forums and haven’t found anyone that has hacked the C1492 control (yet). If these control boxes weren’t so expensive even used on fleabay I’m sure I could convert it to use a vacuum pump instead of compressed air in about 10 minutes.The only problem I see is to figure out how to convert the voltage or current change to power a solenoid valve. I’m thinking a zener and triac for a start but may change my plan after more data is obtained. Too bad they didn’t just use one or both of the non-connected pins, maybe something to do with backwards compatibility or just to make things difficult to hack.Any thoughts or information would be appreciated.
Alternative to Agilent 16117b Low Noise Test Leads? - Page 1
Forum section: electronics / testgear

author: bdwgarrison
author_rank: Newbie
timestamp: July 15, 2015, 03:48:27 pm
content: I have an old HP 4329A High Resistance Meter that needs low noise test leads.The ones referred to in the manual are 16117b Low Noise Test Leads but I was wondering if there's a less expensive alternative. I'm not having much luck shopping around because I'm unfamiliar with the terminology. My guess is that the lower the price, the more noise, but maybe there's an optimal trade-off.Thanks.

author: JoeB83
author_rank: Regular Contributor
timestamp: July 16, 2015, 03:00:38 am
content: Perhaps I'm just an ignoramus, but what are "low noise test leads"? Shielded? Low inductance or capacitance?
Big Difference between Low Noise Test Lead and Standard? - Page 1
Forum section: electronics / testgear

author: bdwgarrison
author_rank: Newbie
timestamp: July 15, 2015, 05:35:00 pm
content: I'm wondering if there is a big difference between a Low Noise Test Lead (Agilent 16117b model goes for $800) and a normal test lead? How much worse of a reading can I expect to get on a High Resistance Meter?Thanks.

author: plesa
author_rank: Frequent Contributor
timestamp: July 15, 2015, 05:58:03 pm
content: This cable has graphite coated insulation to prevent charge generation under shield during cable movement.Also it can use material to reduce electrochemical effect and EMF.It depends on your measurement, my experience that for low noise measurement you need complete shielding and these cables with banana plug are difficult to use.Much better is to use 1:1 cables and some feedthrough.Materials use for insulation are PTFE and PE (material with high isulation resistance, low humidity sensitivity)
SOUND TECHNOLOGY 1710A - In need of some help ! - Page 1
Forum section: electronics / testgear

author: Rosebud41
author_rank: Newbie
timestamp: July 07, 2015, 04:25:15 am
content: Hello,1. I am in need of the rectiangualr push button switch caps "common" to nearly all ST gear form the 70's...I have 2 pc.s missing from my 1710A audio analyzer. Perhaps someone has a boneyard unit, that they could harvest from.?...let me a reasonable cost for 2 pcs.2.

author: Rosebud41
author_rank: Newbie
timestamp: July 07, 2015, 04:31:13 am
content: Hello,1. I am in need of the rectangular push button switch caps "common" to nearly all ST gear from the 70's...I have 2 pcs. missing from my 1710A audio analyzer. Perhaps someone has a boneyard unit (can be sourced form over a dozen ST models), that they could harvest from.?...let me know a reasonable cost for 2 pcs.2. Anyone out there worked on this model before....? Would like to know how you specifically have cleared the various issues, common to these 40 year old units.Let me know...thanks.SG.

author: SoundTech-LG
author_rank: Frequent Contributor
timestamp: July 15, 2015, 03:06:57 pm
content: As you may/may not know, the switch assemblies are the weak link in all the ST17xx series. Intermittent/not working/not available. If you use anything other than IPA or FREON to try to clean up the switches you leave RESIDUE. The residue will change the capacitance. You are left with trying to remove the residue, sometimes impossible to get it out. There are reed relays in these instruments. They are intermittent/noisy/not working. Tapping them may identify/temporarily cure problems. The photodiode variable resistors/couplers are also what? 45+ years old? These are just some of the problems you may encounter...
DS1054Z frequency counter accuracy - Page 1
Forum section: electronics / testgear

author: ralphd
author_rank: Frequent Contributor
timestamp: July 15, 2015, 02:20:32 am
content: I did some testing and found the hardware frequency counter to have an error of less than 2ppm. Pretty good for something I didn't even know I was getting when I bought it!http://nerdralph.blogspot.ca/2015/07/rigol-ds1054z-frequency-counter-accuracy.html

author: mjlinden
author_rank: Newbie
timestamp: July 15, 2015, 02:39:55 am
content: Thanks for posting your research! Good to know...

author: kwass
author_rank: Frequent Contributor
timestamp: July 15, 2015, 05:09:58 am
content: My 1054z is off by about 5pp, still not too bad.

author: AG6QR
author_rank: Frequent Contributor
timestamp: July 15, 2015, 05:25:48 am
content: Interesting. I've got an older 1052E, and it has a roughly similar hardware frequency counter. It's worth emphasizing that the hardware frequency counter on virtually any digital scope is several orders of magnitude better than the frequency displayed by the "measure" function. That hardware frequency counter is a nice bonus feature. If anyone wasn't aware of it, play with it!I'm a ham radio operator. My best HF radio has a TCXO to generate its reference frequency, and I have calibrated that radio using the NIST radio station WWV, which broadcasts precisely on 10.000 000 MHz. The biggest source of error in that calibration is that the propagation path through the ionosphere has a somewhat variable delay, but it's more than good enough for my purposes. Anyway, immediately after calibrating the radio to WWV, I tried measuring its frequency using the DS1052E. I've forgotten exactly how far off the measurement was, but I think it was in the 10s of Hz for a frequency just over 10 MHz -- IOW, something on the order of a couple of ppm. I wasn't being too scientific and writing everything down. I'll have to repeat the test one day, being more careful, and maybe trying it at different temperatures.Another interesting game I have played with that hardware frequency counter is to set it up for AC triggering and precisely measure the frequency of the mains power. No probe needed! Why do I care what the frequency is? Well, I don't care very much, but it's mildly interesting to compare my measured frequency with the frequency as displayed here:http://fnetpublic.utk.edu/gradientmap.htmlThat shows a map of the frequencies of the power grids in the USA, updated in near-real-time. I find that my own measurements with the oscilloscope correlate pretty well with the fluctuations shown on that map. It was a "WOW" moment when I found that site and made my own measurements that correlated with it. Not that it's exactly useful to me, but...