hybridfree/eevblog-posts huggingface dataset:
AC Adapter "LNT-1" for Wandel&Goltermann for SPM-33 Selective Level Meter? - Page 1
Forum section: electronics / testgear

author: jopki
author_rank: Newbie
timestamp: January 24, 2014, 06:35:19 am
content: I just acquired a vintage Wandel & Goltermann Selective Level Meter SPM-33 (200Hz to 1.62MHz) in a local recycling store. It is powered by two (NiCad) 9V batteries but these batteries get sucked out pretty fast. The SPM-33 unit has a 2.5mm jack for an AC adapter that unfortunately didn't come with my unit. The manual says to use Wandel & GoltermannLNT-1 AC adapter / Charger BN2068/01with K491 plug. I have spent many hours looking for more info on the internet in a hope to find what voltage/current the unit needs to be delivered by an external adapter but no luck...I even took the SPM-33 apart in search for clues around the power jack but it just is NOT obvious to me and I really don't want to damage this little device by guessing.If anybody knows what LNT-1 ac adapter (for SPM-33 or SPM-32) provides in terms ofvoltage / max current, could you please let me know?Thanks, JE, Ottawa, Canada

author: svendp
author_rank: Newbie
timestamp: March 09, 2014, 02:08:05 pm
content: Hello I think this Link will give you the information you ned. Best wishes. svendp.http://www.helmut-singer.com/stock/751884364.htmlThe LNT-1 (BN 2068/01) is an AC Line Adaptor/Charger Unit designed specially for use with all of the small, hand-held Wandel & Goltermann test equipment which can be operated from dry- or rechargeable batteries.Output voltages:12 VDC (0,4A)14 VDC (0,15A)28 VDC (20mA)If one output is used, the other is automatically disabled.A LED indicates which output is being used.Please find a corresponding data sheet here.Please find an enlarged image here.Wandel&Goltermann W&G WG Wandel & Goltermann LNT1Maße/ Dimensions : 135mm (B/W) x 55mm (H/H) x 86mm (T/D)Gewicht/ Weight: 0,8 kg
--- - Page 1
Forum section: electronics / testgear

author: ronaldlijs
author_rank: Newbie
timestamp: March 06, 2013, 11:00:44 am
content: ---

author: TheRuler8510
author_rank: Regular Contributor
timestamp: July 21, 2013, 02:28:52 am
content: Ronald,Ever find a manual for your 501J?Tom

author: TheRuler8510
author_rank: Regular Contributor
timestamp: March 04, 2014, 12:16:54 am
content: Quote from: ronaldlijs on March 03, 2014, 10:21:09 pmIt can be fun taking gambles like that. I got mine running by replacing a few power supply capacitors and it runs perfectly now. I never did find a schematic.
Keithly 173A - Page 1
Forum section: electronics / testgear

author: Axtman
author_rank: Regular Contributor
timestamp: March 04, 2014, 05:04:01 am
content: Should I buy a Keithly 173A locally for $35? Are bench DVM a thing of the past?

author: PedroDaGr8
author_rank: Super Contributor
timestamp: March 04, 2014, 05:40:18 am
content: Quote from: Axtman on March 04, 2014, 05:04:01 amBench meters are far from a thing in the past. They are a student beast than handheld meters though. Handhelds often try to be as much as possible because they are portable devices. Bench meters tend to be master's of a few things. For example, typically the precision and accuracy are better. You get 4 wire ohms readings. The 173a has some solid specs for a bench meter. Try finding a solid 4.5 digit handheld meter for that price, let alone with those specs. That being said the one glaring flaw I see is that it doesn't use the more modern shielded banana plugs. It uses basic banana plugs which means you either have to modify your test leads or use basic banana cables.Also, all of this assumes the meter hasn't been abused and is within spec.Sent from my EVO using Tapatalk
REALLY Cheap SA - Page 1
Forum section: electronics / testgear

author: echen1024
author_rank: Super Contributor
timestamp: February 28, 2014, 04:37:26 pm
content: Well, Tequipment have a GW Instek 3 GHz SA for $660http://www.tequipment.net/Instek/GSP-730-DEMO/?v=54585Pissy specs, but probably good for education.

author: tequipment
author_rank: Regular Contributor
timestamp: March 04, 2014, 03:35:39 am
content: We sold it today. The demo that isThanks

author: Psi
author_rank: Super Contributor
timestamp: March 04, 2014, 04:08:31 am
content: With the 5.8ghz band becoming quite common i'm hoping to see some cheap SA's that go up that far. Only time will tell.

author: Electro Fan
author_rank: Super Contributor
timestamp: March 04, 2014, 04:10:33 am
content: There seems to be a non-demo unit listed right beneath the demo for the same price - maybe it's a price error?http://www.tequipment.net/InstekGSP-730.htmlSeems like a lot of SA for the $ if it is correct.

author: echen1024
author_rank: Super Contributor
timestamp: March 04, 2014, 04:23:30 am
content: Quote from: Electro Fan on March 04, 2014, 04:10:33 am3GHz for under $1k is pretty impressive.

author: Electro Fan
author_rank: Super Contributor
timestamp: March 04, 2014, 05:37:19 am
content: I saw a post around here somewhere where a forum member switched from an Instek spectrum analyzer that sold for over $2k to a Rigol DSA815 and he preferred the Rigol - but the Instek 730 might be a good deal....
Excellent Brymen customer support - Page 1
Forum section: electronics / testgear

author: rsjsouza
author_rank: Super Contributor
timestamp: March 03, 2014, 11:01:43 pm
content: I am a happy owner of a BM857 (new old stock, but surely works like a beauty) and some folks reported their excellent customer support - I join their crowd.A couple of weeks ago I wrote to their support e-mail asking about where to purchase a replacement for a broken stand - mine broke a while ago as shown in the first picture (it is not the most robust part of the DMM, I must admit). To my surprise, I received a prompt response from their product marketing department asking for my personal address - they would ship to me a set via air parcel and completely free of charge.So, today the parcel arrived and I was pleasantly surprised to see not only the holster and the stand nicely packaged in a thick bubblewrap envelope with a cardboard insert, but also a pair of the screws and the rubber seals that go around them (second picture - sorry, it is horrid).Thus, I can only recommend Brymen for their excellent customer support to a regular customer like me.

author: Fsck
author_rank: Super Contributor
timestamp: March 04, 2014, 01:30:09 am
content: now.. if only they could make their presence popularized in North America like Fluke or Agilent....

author: rsjsouza
author_rank: Super Contributor
timestamp: March 04, 2014, 02:31:13 am
content: That is something I would love to see materialize, especially considering the horrendously expensive Greenlee branded products or the (somewhat) uncertain quality of the Extech branded ones.In the meantime, I recently purchased fromTMEthe BM857's serial interface adapter (BC-85X-1) - freight was reasonable (about US$20.00) and it arrived in less than a week (shipped Monday, arrived Friday). They carry several Brymen products.

author: HackedFridgeMagnet
author_rank: Super Contributor
timestamp: March 04, 2014, 02:47:00 am
content: QuoteGood to knowI bought 869 and 257 from TME.the 869 is great, one of those tools that makes you happy when you use it.the 257 doesn't really get turned on much. I just got it for it's portability, As the 869 is quite big.

author: Lightages
author_rank: Unknown
timestamp: March 04, 2014, 05:08:20 am
content: I would agree with the support from Brymen. I also have the BM869 and the BM257 along with the BM525. I think the BM257 and the BM869 compliment each other very well. The BM525 is also a very good meter with its internal logging capability.
Looking for service manual for Blackstar LDO 100 Oscillator - Page 1
Forum section: electronics / testgear

author: deephaven
author_rank: Frequent Contributor
timestamp: March 02, 2014, 02:50:30 pm
content: I have a Blackstar LDO 100 with a dead mains transformer. I could guess what the voltage ratings are, but it would be nice to see what they are supposed to be. So, does anyone know where I can get a service manual or know the transformer output windings?

author: sync
author_rank: Frequent Contributor
timestamp: March 02, 2014, 03:05:58 pm
content: http://elektrotanya.com/black_star_ldo100_low_distortion_oscillator_1996_sm.pdf/download.htmlOn this site it takes a few seconds till the download link "Get manual" appears.

author: deephaven
author_rank: Frequent Contributor
timestamp: March 02, 2014, 03:39:33 pm
content: Quote from: sync on March 02, 2014, 03:05:58 pmThanks for the quick reply. I did see that site before, but didn't wait long enough for the link to appear!So, it seems like I need a transformer (I estimate 6VA) with a centre-tapped winding for +/- 15V DC supply and another for a +5V supply (after regulation). Anyone know a source?

author: sync
author_rank: Frequent Contributor
timestamp: March 02, 2014, 04:13:25 pm
content: Finding an off-the-shelf with these secondaries is difficult. But you can use two transformers. One for the +/-15V supply and one for the +5V. What's the problem with the original one?Btw: the manual say the generator has 12VA.

author: deephaven
author_rank: Frequent Contributor
timestamp: March 02, 2014, 04:43:45 pm
content: Quote from: sync on March 02, 2014, 04:13:25 pmThanks, sync, sounds like an idea. The original transformer must have a shorted turn as it gets hot with nothing connected to the secondaries.
Can quality of goldplating be judged by color and shine? - Page 1
Forum section: electronics / testgear

author: quarks
author_rank: Frequent Contributor
timestamp: March 01, 2014, 04:16:14 pm
content: Here is a picture of 4 Kelvin Clips from different brands.

author: dc101
author_rank: Regular Contributor
timestamp: March 01, 2014, 04:35:16 pm
content: Quote from: quarks on March 01, 2014, 04:16:14 pmI can't, but my wife appears to be an expert in that field.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: March 01, 2014, 10:58:11 pm
content: If it's more than a few microinches of actual gold, not much you can say about it really. The surface might have a different finish, evidence of a heavier layer filling in scratches in the substrate?The bottom right seems awfully tin plated, but that might just be the lighting.On the upside.... they're Kelvin clips, so it doesn't matter!Tim

author: ajb
author_rank: Super Contributor
timestamp: March 02, 2014, 02:32:20 am
content: Looks in this case like different surface finishes on the base metal more than anything else. The ones on the right look like they have not had much if any finishing done after being stamped and formed, whereas the ones on the left look like they've been much more precisely stamped and then ground or blasted/tumbled to provide a matte surface.
Just bought first scope. How'd I do? - Page 1
Forum section: electronics / testgear

author: photonpunk
author_rank: Regular Contributor
timestamp: March 01, 2014, 11:23:33 pm
content: I've been looking for a good deal on an analog scope for a while. After striking out on ebay for the last few months, I decided to drive to the nearest hamfest and try my luck there.I ended up coming home with this Leader LBO-508 50mhz 2-channel scope. According to the seller, it was calibrated 3 months ago. I talked him into throwing a used probe into the deal. Paid $70.

author: amtpdb
author_rank: Regular Contributor
timestamp: March 01, 2014, 11:55:22 pm
content: Glad to see you were able to get a decent looking scope. I have been trying for over a year with no luck. I went to a ham fest after hearing about them. All the scopes I saw were either broke or in terrible shape. They looked like they got them at a bulk auction of recycled parts. Tried ebay and purchased one. Had to return it as it was in bad shape even though the seller said good. Cost me 100. in shipping to get some money back. Good luck with the scope.Don

author: MatCat
author_rank: Frequent Contributor
timestamp: March 01, 2014, 11:58:24 pm
content: If it works well then you did good hehe. A lot of times most scopes just need some caps replaced, clean the pots, etc and usually they will be fine, most dead scopes on ebay are going to be a simple fix.

author: photonpunk
author_rank: Regular Contributor
timestamp: March 02, 2014, 05:38:27 am
content: I played around with it some, and as far as I can tell everything works. I'll have to brush up on some tutorials though because it's been a long time since I used one of these.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: March 02, 2014, 06:05:21 am
content: Don't know the performance and features of that scope (looks like, single beam dual channel, basic triggered sweep..?), but the bandwidth is good for the price!Tim

author: true
author_rank: Frequent Contributor
timestamp: March 02, 2014, 07:55:38 am
content: It'll do you well. Nothing great, but nothing bad either,
Rigol Scope for I2C decoding - Page 1
Forum section: electronics / testgear

author: TheRuler8510
author_rank: Regular Contributor
timestamp: February 21, 2014, 02:08:46 am
content: Does anyone use a Rigol scope for I2C decoding? Mine is a DS4024.I noticed that sometimes it will decode the address incorrectly. For instance, instead of 0x77 it will say 0x38, but if I then change the format to ASCII then back to hex, it is correctly reading 0x77.I only saw this happen a few times so-far. I still have a few hours on my demo I2C license. Should I buy the permanent license?

author: ttp
author_rank: Regular Contributor
timestamp: February 21, 2014, 08:42:33 am
content: I think you are in good position to talk to Rigol, tell them you got a new DS4024 and want to buy I2C license but there is a problem you have observed... They might be interested in replicating/resolving the problem.

author: TheRuler8510
author_rank: Regular Contributor
timestamp: March 01, 2014, 10:23:10 pm
content: Quote from: ttp on February 21, 2014, 08:42:33 amI can't seem to repeat the problem...funny how that happens.Maybe I was delirious at the time.
Rigol DP832 Question and Problem - Page 1
Forum section: electronics / testgear

author: 99tito99
author_rank: Regular Contributor
timestamp: March 01, 2014, 05:33:08 am
content: Just received a new Rigol DP832 today:Digital v.: 00.01.08.00.02Analog v.: 01.02.00.01.02.00Boot v.: 01.05Keyboard v.: 01.01With big shiny aluminum heat sink (probed with a 87V thermocouple and got ~55°C).Question:On Dave’s v-blogs his DP832 displays 3 significant figures (i.e. 00.000) for voltage and mine displays 2 (i.e. 00.00). Why?Problem:After un-boxing I hooked up 100 watt 10? resistors to each channel and ran the voltage up to get about 2.5A on CH1&2 and 0.5A on CH3 for about an hour. I then set the voltage on each channel to zero, however the channel 2 output displays 00.01 (set 00.00). I don’t think this was the case before I did my bake-in.Appreciate any thoughts.Cheers,Mark****************************

author: Skimask
author_rank: Super Contributor
timestamp: March 01, 2014, 05:46:58 am
content: Q) Because Dave has the high accuracy software upgrade.P) Can't remember the answer, but it's somewhere here in the forums.

author: 99tito99
author_rank: Regular Contributor
timestamp: March 01, 2014, 05:00:22 pm
content: Quote from: Skimask on March 01, 2014, 05:46:58 amThanks:Somehow I spaced-out on the high accuracy option which I saw it, but it did not register.As for the problem I'm need to do a bit more searching. My guess is it's a calibration issue.Cheers,Mark
Do any current DSOs return FFT phase information? - Page 1
Forum section: electronics / testgear

author: David Hess
author_rank: Super Contributor
timestamp: February 25, 2014, 01:22:44 pm
content: I am looking for DSOs that return the FFT phase information as well as the magnitude instead of throwing it away. This is handy for quick and dirty low frequency vector network analysis where an FFT of the impulse response is used in place of a swept measurement. Some older Tektronix TDS series DSOs can do this but only the highest end of currently produced DSOs can.

author: rfbroadband
author_rank: Unknown
timestamp: February 28, 2014, 05:25:44 am
content: yes the R&S RTO scopes do...

author: David Hess
author_rank: Super Contributor
timestamp: February 28, 2014, 05:45:59 am
content: I was aware that R&S oscilloscopes supported this but I am not sure I would consider anything they make to be other than the highest end.The old Tektronix TDS series starting at about the TDS520 supported magnitude and phase either optionally or standard but the slowest models were 500 MHz and they are not maintenance friendly so buying one used is a significant risk.

author: Mark_O
author_rank: Frequent Contributor
timestamp: March 01, 2014, 03:05:56 am
content: Quote from: rfbroadband on February 28, 2014, 05:25:44 amrfbb, the R&S RTO series are certainly very cool, and capable. But they're what you find when you look in the dictionary under "the highest end of currently produced DSOs".They cost considerably more than my car. In fact, I think they cost more than a home I once lived in, many years ago.I may get an R&S RTO someday... when I die. That is,ifI go to heaven. If I wind up in the other place, I'll probably get stuck with an Owon.

author: rfbroadband
author_rank: Unknown
timestamp: March 01, 2014, 03:46:24 am
content: Mark_O, well not sure what to say. I like your sense of humor. Yes you are correct they are expensive, but not any more expensive than an Agilent scope in the same class of instruments (Infiniium 9000 series). But if you compare a x MHz RTO against any other x MHz scope, you are correct, they are the highest end scope you find on the market and outperform every competitor (well based on the info I have and the scopes I looked at).

author: David Hess
author_rank: Super Contributor
timestamp: March 01, 2014, 05:12:47 am
content: The lower end R&S oscilloscopes apparently lack this feature anyway although I am not completely sure since their marketing department apparently prefers to hide their specifications and user manuals.

author: zapta
author_rank: Super Contributor
timestamp: March 01, 2014, 05:21:39 am
content: Quote from: Mark_O on March 01, 2014, 03:05:56 amDoesn't matter what tools you have, what matters is what you build with them. ;-)
DS1000Z FFT usability problems - Page 1
Forum section: electronics / testgear

author: jadew
author_rank: Frequent Contributor
timestamp: February 17, 2014, 01:43:56 am
content: Hey guys,I'm wondering if I'm missing something/doing something wrong or if this scope really fails when it comes to FFT display. I find it extremely difficult to keep the display on screen. Every time I'm adjusting a value, it goes off screen and I have to scroll it back into view, both horizontally and vertically (depending on what I change).Is there some setting I'm not aware of? Is this normal behavior (altho I don't remember having this issues on the DS1052E)?Any tips on how to handle it?Thanks

author: rfbroadband
author_rank: Unknown
timestamp: March 01, 2014, 04:05:28 am
content: unfortunately that is pretty typical for many scopes.
Amazon Supply - Page 1
Forum section: electronics / testgear

author: zapta
author_rank: Super Contributor
timestamp: February 28, 2014, 03:24:43 pm
content: Just stumbled upon this one. Amazon has a frontend for technical supply, competing with Grainger, MxMaster and the likes.http://www.amazonsupply.com/For examplehttp://www.amazonsupply.com/s?page=1&size=20&ref_=sp_s_node_256409011&uah=k%3Admm&uap_n=256409011&x=0&y=0

author: saturation
author_rank: Super Contributor
timestamp: February 28, 2014, 03:34:54 pm
content: Wow. Thanks, worth a look. It reminds me most of McMaster Carr.

author: robrenz
author_rank: Super Contributor
timestamp: February 28, 2014, 03:45:27 pm
content: This is the original SmallParts.com that got borged by Amazon. Unfortunately with a lot of the hard to find stuff that I used to go there for they seem to be just selling off the stock they had and not carrying it anymore. You used to be able to get any size hypodermic tubing in various lengths and the same with polyimide tubing. Now the stock list is hit or miss with no signs of it being replenished. Very sad

author: nanofrog
author_rank: Super Contributor
timestamp: February 28, 2014, 09:23:30 pm
content: Quote from: robrenz on February 28, 2014, 03:45:27 pmThat is sad.I remember buying small gears and such from them in the past for projects.

author: Stuey
author_rank: Contributor
timestamp: March 01, 2014, 02:10:26 am
content: Quote from: robrenz on February 28, 2014, 03:45:27 pmYup.I was happier when Small Parts was a little separate.I don't understand why Amazon companies like Zappos and Woot operate independently but Small Parts couldn't.
Quick question about Fluke 287 - Page 1
Forum section: electronics / testgear

author: RoTTe
author_rank: Contributor
timestamp: February 28, 2014, 07:14:57 pm
content: Hi there!I bought an used Fluke 287. Everything looks right, the odd thing is that the multimeter indicates that the serial number is "#20".Is this possible ? The calibration is dated 2007.Thank you!
New Agilent MSO 9000 firmware - Page 1
Forum section: electronics / testgear

author: dc101
author_rank: Regular Contributor
timestamp: February 26, 2014, 12:33:55 pm
content: Looks like Agilent just pushed out a major update for their scopes. Hard to tell from the videosbut looks like it's only for the 9000 series scopes. Very nice though, check out the FFT!https://www.youtube.com/channel/UCSF3S7wkXmZutI2npA3SuRw-Tim

author: dfnr2
author_rank: Regular Contributor
timestamp: February 28, 2014, 03:06:33 pm
content: The gestures look nice. I wonder which infiniiums have capacitive touch screens. I don't think the 9000 series do. Perhaps the 9000H series?
Instek GDS-2074A Noise / Resolution - Page 1
Forum section: electronics / testgear

author: katzohki
author_rank: Frequent Contributor
timestamp: February 27, 2014, 09:07:10 pm
content: I've recently acquired a GW Instek GDS-2074A oscilloscope to use at work. There are a lot of things I like about it, the waveform update rate, the screen and so on. But it has a problem that is really making it seem like it's not so good. I'll try to be as detailed as I can, but if I've left something out then tell me and I'll try to add it in.There seems what I would describe as "noise" which is proportional to the Volts/Div setting. I've tried a variety of settings and the only thing that gets rid of it is the digital filter being set at 20MHz in the Acquire menu. Obviously that isn't really a good solution.To me it seems like the ADC kind of hovers between two values in the least significant bit and it switches between them constantly. That wouldn't be so bad, because I don't expect it to be perfect down in its smallest range... But even when I have it set to 10V/div, the "noise" is still between 1/5 and 1/10 a division. That's noise between one and two volts! Also, if I pause/stop the scope and then increase the Volts/Div this noise does increase as well and it is also in the captured data.Is this just because it is an 8-bit converter and it's sort of normal behavior? If you guys can help me out I'd really appreciate it. If it's just because it's a crummy feature I'll live, but if it's a real error, then I need to get it replaced.Also the stupid self cal always crashes. Probably not related?I've included a couple saved traces and a spreadsheet with captured data. One of the carts is a close up of the top of the waveform.Thanks!

author: marshallh
author_rank: Unknown
timestamp: February 27, 2014, 11:55:14 pm
content: you're displaying an 8-bit quantized signal with only 256 possible levels on a 800x600 display. Totally normal

author: katzohki
author_rank: Frequent Contributor
timestamp: February 28, 2014, 02:41:22 pm
content: OK Thanks. Now I just have to decide what to do.
Used digital scope recommendations - Page 1
Forum section: electronics / testgear

author: Axtman
author_rank: Regular Contributor
timestamp: February 19, 2014, 07:36:18 pm
content: There is hamfest (in the US) in a few weeks and I am in the market for a used digital scope. What should I look for and what should I avoid? I am an electronic hobbist that does not need top performing professional gear. I would like to find something around $400. I guess that I should get a name brand and one that I can find documentation for easily. Did Tektronix or HP make some real dogs that I should avoid?

author: David Hess
author_rank: Super Contributor
timestamp: February 28, 2014, 07:18:58 am
content: I would avoid any DSO that lacks a peak detect mode which rules out anything older than a Tektronis 2230 or 2232 but the only DSOs I have seen at hamfests are relatively recent if used modern DSOs of the inexpensive Asian import variety. Full service documentation is unlikely to be available for any DSO newer than the Tektronix 2440 series (20+ years old) so there is a relatively narrow range and age of DSOs which meet both of those requirements.With diligence any of the above mentioned oscilloscopes in working but used condition can be had for less than $400 but you can also probably find a low performance modern although undocumented instrument in that range as well. I am not very familiar with the old HP instruments which would qualify.

author: Axtman
author_rank: Regular Contributor
timestamp: February 28, 2014, 07:36:14 am
content: I checked out a Craigslist ad the other day for an electronics assembly plant that was surplussing some used equipment. They had an HP 1980B and an HP 54111D digitizing oscilloscopes. Both of which I checked out and could not get to work properly (though I am not exactly sure what I am doing). So I bought 2 analog scopes (Tek 265 and BBC Goerz Metrawatt) and a signal generator (Wavetek 182A) instead.

author: David Hess
author_rank: Super Contributor
timestamp: February 28, 2014, 07:41:22 am
content: What model of analog oscilloscopes did you buy? I make good use of my various analog Tektronix oscilloscopes but my 2230 combination analog and digital storage oscilloscope is what I use most.With old but serviceable oscilloscopes is pays to have two so one can be used to repair the other.
Teardown: Daven 650-50 Attenuation Network[boring resistors,switches,from ebay] - Page 1
Forum section: electronics / testgear

author: babysitter
author_rank: Frequent Contributor
timestamp: February 20, 2014, 09:13:07 pm
content: Not too bad for 50$ oneBay auction: #who careswith acceptable shipping to Germany...Some cleaning with Baby oil, Tuner spray and cotton swab on the outside was necessary.This device, quite unknown at the omniscient landfill named www, is a 50 Ohm 0-100 dB , 1 dB step attenuator.Each switch, when pressed, engages a single Pi-shape attenuator with the corresponding value, when not pressed, the signal is routed trough without intended attenuation. The configuration is 1+2+3+4+10+10+10+20+20+20 dB.Impedance and connection: 50 Ohms N female. Estimated max. input power around 20 dBm. Don't want to cook it for testing.Bandwith: Depends on your requirements, it seems to be really flat to ~200 MHz but acceptable up to 450 Mhz where it rolls off rather steep. Better measurements will follow here, Baby prevents me from finishing the measurement.Now, lets get some Verzwakker show ! (Sorry people from the nederlands, PA4TIM I am looking at you!)The boring outside, hinting on quite a age. All the good stuff is behind the front panel, the back of the housing is only for stand and protection without active parts.2 groups of 5 attenuators in sub housings behind the switch rows, cabling between the sub housings and the N connectors in RG-58.Pron starts here: the diecast sub housings have 5 chambers, each contains a PCB-based switch and the corresponding pi-constellation attenuator. The additional resistors from ground to somewhere invisible, any idea what they are ?A bit more description in german athttp://dg3hda.primeintrag.org/doku.php?id=daven_650-50

author: SoundTech-LG
author_rank: Frequent Contributor
timestamp: February 20, 2014, 09:46:02 pm
content: Don't know about that one, but these are nice, I love mine... good to 1 mHz...http://www.ebay.com/itm/HP-350D-Attenuator-Set-5W-55V-600Ohm-DC-IMC-/300956945533?_trksid=p2054897.l4276#ht_388wt_1121But the one you really want if you can live below 560kHz is the 353A Patch Panel very very nice. Looking for another one.

author: babysitter
author_rank: Frequent Contributor
timestamp: February 27, 2014, 08:21:04 pm
content: As promised, the measurement of attenuation over frequency.ConditionsMade with a Rigol 815-TG, using 2x ~50 cm N(m)-BNC(m) some 7mm type coax cable and 2x BNC(f)-N(m) adapters.Tracking generator setting at -20 dBm "normalized" to 0 dBm line with a N(f)-N(f) barrel adapter before putting the attenuation network inline. No additional inline attenuators used.The plotThe blahThe Marker shows the 3 dB bandwidth of the low pass characteristic.The 2 m ham band (EU) is well within the useable range.At the 70 cm ham band (EU) it is already down at the steep edge of the low passNote the curious decrease of attenuation above 600 MHz, fun guaranteed when using a power meter and a source with harmonicsConclusionI consider that a good result for a "feeling lucky" ebay experiment at that price.
help with id of frequency range added more pic teardown  - Page 1
Forum section: electronics / testgear

author: plakat
author_rank: Newbie
timestamp: February 27, 2014, 08:25:50 pm
content: Hi ,I have an old Hanson fs-5e and I have no idea of it's working frequency range.it was my dad's back in the 80s ,I can only find info on the fs-5. And it completely differant.I was hoping it's range maybe 3 mhz upto around the 150mhz but a guy I asked a while back at a auction said he thought it topped out at 30mhz .can anyone point me in the direction of some accurate info I have googled it to death ....

author: babysitter
author_rank: Frequent Contributor
timestamp: February 27, 2014, 08:37:45 pm
content: Teardown photos might help, maybe someone can give hints upon seeing the construction of the coupler...... otoh, why dont you try / let someone else try ?

author: plakat
author_rank: Newbie
timestamp: February 27, 2014, 08:53:59 pm
content: I'll pull it apart now and post the pics thanks for the advise I'll post back up in about one hour

author: katzohki
author_rank: Frequent Contributor
timestamp: February 27, 2014, 09:10:14 pm
content: 3MHz to 30MHz would be fairly typical of amateur radio gear. Generally considered the "HF" range.

author: dc101
author_rank: Regular Contributor
timestamp: February 27, 2014, 09:59:44 pm
content: Manual attached... 3-144 MHz.

author: plakat
author_rank: Newbie
timestamp: February 27, 2014, 10:06:24 pm
content: Hi thanks for that but that's the fs-5 it's totally different if you check the above pictures this is the tear down but not great pics but you rf guys may have a much better idea thanks again

author: kc9qvl
author_rank: Regular Contributor
timestamp: February 27, 2014, 10:31:43 pm
content: Some one already posted this. Disregard

author: plakat
author_rank: Newbie
timestamp: February 27, 2014, 11:12:28 pm
content: Its turning out to be a challenge to find any info on this unit ,if anyone in any country has any info please add your input ti the post .thanks again ...
Need a manual for the Kepco BOP36-5M - Page 1
Forum section: electronics / testgear

author: uoficowboy
author_rank: Regular Contributor
timestamp: February 27, 2014, 06:09:23 pm
content: Anybody have any suggestions as to where to find a manual for a Kepco BOP36-5M?Kepco previously has been helpful in sending PDFs of their manuals, but this time they're demanding payment. Lame.
cheap calibration for 34401A in California Bay Area? - Page 1
Forum section: electronics / testgear

author: djacobow
author_rank: Super Contributor
timestamp: February 26, 2014, 07:07:57 pm
content: I am the proud owner of a new-to-me HP34401A. It appears to have been never calibrated, aside from at the factory (calibration count 35) and that was in April of 1997.So it's due.Of course, I'm a hobbyist, so I'm looking for something relatively inexpensive. I do not have access to any more accurate equipment myself.Thanks,Dave JPS -- the unit really really stinks of Old Spice and, I think, menthol cigarettes. I can smell it in any room I take it into. Anybody have any advice for cleaning? I've already run the bumpers through the dishwasher and scrubbed the external case down with soap, baking soda, and vinegar, all to no avail. I obviously don't want to go inside the unit, and I can't imagine it would need it anyway, since it's not a vented design. Looking for ideas!

author: linux-works
author_rank: Super Contributor
timestamp: February 26, 2014, 07:22:01 pm
content: kitty litter. lol. but its been listed as one way to deoderize smokey old ebay items.I got stuck with an hp power supply that was nasty, like yours sounds. tried febreeze (lots of it) and kitty litter. kept a fan over it and left it outside for days (in dry summer days). it just took lots of time in a clean air room for the smell to finally go away. chemical cleaners didn't seem to help. time in a clean area (like, a year!) was the only thing that really did the trick.

author: djacobow
author_rank: Super Contributor
timestamp: February 26, 2014, 08:15:05 pm
content: Thanks for the reply. Yeah, my lab/shed is not sufficiently ventilated for this purpose. Looking forward to leaving it out on some sunny warm days, and will store the unit somewhere that gets good airflow!

author: linux-works
author_rank: Super Contributor
timestamp: February 26, 2014, 08:31:49 pm
content: last year, I had to move a lot of my lab gear into storage and it sat there (in a garage-like storage locker) for most of a whole year. when I moved it all out, I noticed the smell was essentially all gone.there wasn't any airflow in there (minimal) so it had to just be 'time' in a non-smelly room that caused it to finally chill outI really complained to the ebay seller, too; for something this odorous should have been described as such. its the honest thing to do.
10 years warranty for Siglent SDG1025???? - Page 1
Forum section: electronics / testgear

author: Terry
author_rank: Contributor
timestamp: February 26, 2014, 09:40:42 am
content: OMG!!!I saw 10 years warranty for Siglent SDG1025?advertising in EEVBLOG front page by a Sainsmart company.can this be true??maybe after 10years i'll absolutely use a new one, but this long warranty still very fascinating...

author: tautech
author_rank: Super Contributor
timestamp: February 26, 2014, 09:55:46 am
content: Quote from: Terry on February 26, 2014, 09:40:42 amI have not had such a Memo from Siglent.Too late to check with them today....nearly 6 PM there now.3 years is the standard Siglent warranty.A deal like that(if you can hold them to it) has to be worth something.

author: f1rmb
author_rank: Regular Contributor
timestamp: February 26, 2014, 12:19:47 pm
content: Hi,Fortunately I bought one from them last friday, but didn't noticed this extra warranty... Thanks for the tipOTOH, where would I be in 10 years ?Cheers.

author: nowlan
author_rank: Frequent Contributor
timestamp: February 26, 2014, 12:31:36 pm
content: 2 years in binary perhaps?

author: rf-loop
author_rank: Super Contributor
timestamp: February 26, 2014, 04:48:44 pm
content: Quote from: tautech on February 26, 2014, 09:55:46 amSiglent factory warranty is 3 year or what Siglent have stated with product.This Sainsmart 10 year warranty comes from Sainsmart itself: "It comes with 10 yearsWarranty by Seller"Of course distributor can expand warranty as they want but seller is himself responsible what he promise, not Siglent.

author: mainman
author_rank: Regular Contributor
timestamp: February 26, 2014, 05:17:41 pm
content: Warranty LOL Siglent does not honor their warranty. My brand new Siglent Dso SHS810 was only out the box for 3 seconds when it failed and Siglent wouldn't fix or replace it with a model of equal value.Go here and read about my problem with their product and watch the video I recorded of the actual fault me and another buyer had with our brand new out the box DSO made by Siglent.https://www.eevblog.com/forum/testgear/siglent-technical-support-join-in-eevblog/150/In the end both of us had to fix our own DSO without help from Siglent, in my case after trying to get siglent to fix or replace it themselves they actually tried to offer me a product of LESSER specifications as a exchange ( I still have the email to back this up ) so I would go away. Horrible company will never buy from again.
LCR Characterization techniques? (LCR200 vs DE 5000) - Page 1
Forum section: electronics / testgear

author: bronson
author_rank: Regular Contributor
timestamp: February 19, 2014, 08:15:04 pm
content: Anyone have any good tricks to put an LCR meter through its paces?The DE 5000 showed up crazy early (3 days after ordering, from Japan) so, for the next few days, I'll have both meters on the bench.I'll run through some ordinary components and some trickery (resistors and caps in series and parallel, filters, coiled leads, etc) but I can't think of anything really novel.I think both these meters use the same chipset internally (Cyrustek ES51920) so I'm not expecting many differences but I figured this was a neat opportunity. I can try shooting some vid if anyone's interested.How can I make these meters sweat? Short of 220V I mean?

author: mainman
author_rank: Regular Contributor
timestamp: February 19, 2014, 08:32:04 pm
content: Quote from: bronson on February 19, 2014, 08:15:04 pmYes I am definitely interested in your opinion on both these meter seeing you can do a side by side comparison. I am on a budget and would be grateful to know if I can fly by with the cheaper LCR2000

author: astra
author_rank: Contributor
timestamp: February 25, 2014, 09:04:52 pm
content: +1 for the comparision...astra.
Anybody used a Fluke 771 or similar clip on ammeter? - Page 1
Forum section: electronics / testgear

author: uoficowboy
author_rank: Regular Contributor
timestamp: February 25, 2014, 07:40:44 pm
content: I recently became aware of theFluke 771. It seems pretty cool - you can clip it on to a wire and then get a current measurement with pretty high accuracy and resolution. It only has two ranges - a 20ma and a 100ma range - so that's a bit limiting. But overall this seems like a really cool tool.I also saw anHP 428Brecently. Similar idea, but wider current measurement range. It is a pretty massive tool though and vacuum tube based, so less attractive, but still cool.Anybody here have a clip on ammeter that can do low current measurements? Before seeing these two I thought that only worked for high current stuff, but clearly I was mistaken! Do you find them to be useful tools?Thanks!

author: georges80
author_rank: Frequent Contributor
timestamp: February 25, 2014, 07:58:01 pm
content: I use an Extech that can resolve to 10mA DC. It's handy for quick checks of input/output current on my LED drivers. Accuracy is not wonderful since the sensing can be 'influenced' by external magnetic fields, but fine for my go/no-go testing/verifying.I use a Tek AC/DC 50MHz clamp probe system when I need to 'see' waveform details on my scope.cheers,george.
Fluke 179 or 87-V? - Page 1
Forum section: electronics / testgear

author: grips03
author_rank: Contributor
timestamp: February 25, 2014, 04:01:30 am
content: Fluke 179 or 87-V. 87-V is about $80 more, but is it worth it?Are both made in the USA?Does on have much better features than the otherWill be used for home electronic type use.thanks

author: echen1024
author_rank: Super Contributor
timestamp: February 25, 2014, 04:16:56 am
content: 87-V for electronics. Has uA.

author: gaijin
author_rank: Contributor
timestamp: February 25, 2014, 04:31:24 am
content: The 179 lacks relative mode, which can make it annoying to use.

author: AG6QR
author_rank: Frequent Contributor
timestamp: February 25, 2014, 05:25:20 am
content: Both are made in USA, both have "lifetime" warranty (which really means until the product is discontinued plus a few years -- forgot the exact details, but look them up). Both have quality input protection, fast autoranging, fast latching continuity beep, bar graph. Both are rugged meters which will perform to specifications very well, even after being dropped and subject to mishandling.87-V has up to 20000 counts, vs 6000 for 179, but download the manual and look at it for how the 20000 count option works -- it's not always on. 87-V also has a bit better basic DC accuracy. 87-V has the low pass filter for motor drive applications. 87-V has microamps. It also has duty cycle. 87-V has conductance, which is the inverse of resistance. With the 179, you can measure resistance, put it into a calculator, and hit the 1/x button.Most of the time, both meters will do the job equally well, but there are definitely some extra features in the 87-V. Worthwhile? Maybe. I can't think of anything the 179 does better than the 87-V.I have the 179, and am very happy with it, but if I were doing it over, I just might spring for the 87-V.

author: retiredcaps
author_rank: Super Contributor
timestamp: February 25, 2014, 07:44:40 am
content: Quote from: grips03 on February 25, 2014, 04:01:30 amIf you are looking at Fluke, have you considered the Fluke 28 II that Dave reviewed? I'm not sure what kind of pricing you will get though.

author: grips03
author_rank: Contributor
timestamp: February 25, 2014, 04:47:23 pm
content: Ordered the 87-V today, the 28 II looks nice, but its a bit too much money for me.I really like my Fluke 115, but its missing some features, hence the upgrade to the 87-V. Hopefully this is the last meter I need to buy.

author: echen1024
author_rank: Super Contributor
timestamp: February 25, 2014, 05:04:07 pm
content: Quote from: grips03 on February 25, 2014, 04:47:23 pmThe 28-II is only necessary if you're going to seriously abuse your meter.

author: Fsck
author_rank: Super Contributor
timestamp: February 25, 2014, 05:23:25 pm
content: Quote from: retiredcaps on February 25, 2014, 07:44:40 amA Fluke 28-II is basically a super rugged version of the 87-V. if I remember correctly, they have almost identical specs.
Connector ID - Page 1
Forum section: electronics / testgear

author: Axtman
author_rank: Regular Contributor
timestamp: February 27, 2014, 02:03:44 am
content: What type of connector is this thing? I found it in my junk box.

author: taemun
author_rank: Regular Contributor
timestamp: February 27, 2014, 02:10:32 am
content: Might be an ESD grounding pad connector?

author: Axtman
author_rank: Regular Contributor
timestamp: February 27, 2014, 02:18:26 am
content: That was kind of my guess. I just need a snap in wrist band. I think?Does anybody else venture to guess?

author: Nerull
author_rank: Frequent Contributor
timestamp: February 27, 2014, 02:21:41 am
content: Ground connector for an ESD mat, with banana sockets for wrist strap cords.Similar to this one:

author: Axtman
author_rank: Regular Contributor
timestamp: February 27, 2014, 02:36:34 am
content: Great! Thanks!
Fluke 87V questions - Page 1
Forum section: electronics / testgear

author: London Lad
author_rank: Regular Contributor
timestamp: February 25, 2014, 01:37:15 pm
content: Hi All,I've just acquired a second 87V in my long term quest to reduce and standardize my herd of DMMs :-)The latest one, which I suspect may be older than my original, is in good order except for the fact that it arrived with a new set of VERY cheap probes and a blown 10 amp range fuse.The meter works fine and is as accurate as my original unit however its continuity beep is only about half the volume of the originals and the display is a different 'colour'My question is, are there different versions of the 87V and was the beep volume / display type changed at some stage and does anyone know where to get reasonably priced Fluke DMM11A fuses in the UK ?

author: Marvin
author_rank: Contributor
timestamp: February 25, 2014, 02:13:06 pm
content: If you take a look at EEVblog #185 - Fluke 87V Multimeter GSM Fix! @Dave compares his older and the new revision of 87V to have the GSM issue fix - he notes that the display looks different and there are other minor differences. Fluke does silent changes inside a model with no real online documentation of changes. They probably changed the beeper manufacturer at some point and this is not a malfunction.

author: London Lad
author_rank: Regular Contributor
timestamp: February 25, 2014, 02:20:15 pm
content: Thanks Marvin, that's probably one of the few vids I've not watched yet
Type of RF connector inside HP 8901A? - Page 1
Forum section: electronics / testgear

author: JLM
author_rank: Contributor
timestamp: February 24, 2014, 02:30:41 am
content: I have an HP 8901A modulation analyzer. I need to adjust the internal frequency counter, which is accomplished by feeding a 10 MHz external signal onto an RF port inside the machine and then adjusting a pot. I am not familiar with the name of the connector -- it's really tiny though and is gold colored. It"s a female, and there are several male to male cables of this connector type jumping between various ports. Once I know the name of the connector I can order one and then rig a cable to take a BNC output from my frequency source into the analyzer. Do any of you know the name of this connector?

author: aholtzma
author_rank: Contributor
timestamp: February 24, 2014, 03:16:27 am
content: Best if you post a photo. Your 'gold and tiny' description could match just about any RF connector.

author: VK5RC
author_rank: Unknown
timestamp: February 24, 2014, 05:49:57 am
content: Try looking up the microwave encyclopaedia, it has a good " identify that rf connector" section, a common inside the box connector is a smb, often confused with mcx, best of luck.

author: bbarry
author_rank: Newbie
timestamp: February 24, 2014, 07:28:53 am
content: I believe they are SMC connectors.

author: JLM
author_rank: Contributor
timestamp: February 24, 2014, 01:22:26 pm
content: Here's a photo. Please advise

author: c4757p
author_rank: Super Contributor
timestamp: February 24, 2014, 01:37:03 pm
content: Well, after carefully enhancing the image...I've come to the conclusion that they look kind of like SMB connectors.

author: JLM
author_rank: Contributor
timestamp: February 24, 2014, 01:58:19 pm
content: LOL!!! Here's a close up...

author: c4757p
author_rank: Super Contributor
timestamp: February 24, 2014, 02:03:23 pm
content: SMC.

author: w2aew
author_rank: Super Contributor
timestamp: February 24, 2014, 02:03:51 pm
content: That's an SMChttp://www.microwaves101.com/encyclopedia/connectors_smc.cfm

author: JLM
author_rank: Contributor
timestamp: February 24, 2014, 02:24:44 pm
content: Thanks!! ps - I love your vids, have learned so much from them