hybridfree/eevblog-posts huggingface dataset:
Fluke 8840A normal behavior?? - Page 1
Forum section: electronics / testgear

author: PwrElectronics
author_rank: Regular Contributor
timestamp: May 11, 2020, 02:30:48 pm
content: I have this Fluke 8840A that came from the dumpster a few years ago with a tag stating some resistance ranges were out of cal. I had a prior post about that....Due to the pandemic, I have been working in my home lab and have been using this meter for DC voltage measurements. If I measure a voltage, then removed my probes, the meter still shows what I was measuring, but with a very slow "discharge". If I short the leads together, it will zero or if I move my leads to a different voltage, it follows that.This is not "normal" compared to other meters I have or ever used in the past. For example, I also have a Fluke 45 and for my testing, I have been using both meters to measure the same things and the 45 will zero when I remove the leads from my test point. So do my handheld meters.Is this normal behavior for this or is something wrong with it and if so, what?The measurement accuracy seems fine or it agrees with the 45 within 1mV or so, etc. Just does not zero when leads are floating.

author: hugo
author_rank: Regular Contributor
timestamp: May 11, 2020, 03:42:03 pm
content: This is normal and it is caused by the very high input impedance (10 GΩ in the 0.2, 2, 20 volt ranges)

author: AVGresponding
author_rank: Super Contributor
timestamp: May 11, 2020, 04:03:33 pm
content: Love my 8840A...That 10GOhm is a minimum, it may be higher!These things generally don't drift much unless they get abused with large temperature changes, overloaded inputs etc.The 8840A has five times the accuracy of the 45, btw...You can find service manuals for both meters on the elektrotanya website:https://elektrotanya.com/fluke_8840a_digital_multimeter.pdf/download.htmlhttps://elektrotanya.com/fluke_45_sm.pdf/download.html

author: PwrElectronics
author_rank: Regular Contributor
timestamp: May 11, 2020, 06:54:08 pm
content: ThanksIn 30+ yrs in electronics, I have never used a meter that behaved like this so I wondered.

author: DrijSkij
author_rank: Contributor
timestamp: December 18, 2024, 02:35:49 pm
content: Mine does the exact same thing. Good to know.
Teardown and restauration of a Citizen CQT-101-C Quartz Tester - Page 1
Forum section: electronics / testgear

author: BreakingOhmsLaw
author_rank: Frequent Contributor
timestamp: May 08, 2020, 11:43:40 pm
content: As promised in TEA, here is a teardown and restore of a Citizen CQT-101 Quartz tester.https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/msg3056850/#msg3056850Inside:It is very dirty and does not work well. The measurement jumps a lot.First, i'll clean the thing. To get the grime off, I use an industrial grade alkaline cleaner called TG-20. The stuff works like a charm. Spray it on, wait 10 seconds, wipe clear.I removed all boards and started testing the caps. They are all quality stuff by Nippon Chemicon, but nevertheless. One 1000uF on the power supply is dry as a dead dingos reproductive organ.Reason enough to doubt them all. I am going to recap the entire unit. The dead power suply cap probably caused the jumping measurements. I could not be bothered to measure the ripple though.I did check the OCXO, which came in at 4.319.899 Hz. That said, i did not run the counter on my rubidium source as it was not properly warmed up. The internal clock is about 3ppm off, so the CQTs OCXO needs to be adjusted later. Not going to tocuh it until the new caps get in.Here's the money shot - OCXO guttedto be continued

author: isacco
author_rank: Newbie
timestamp: December 18, 2024, 08:27:01 am
content: Hi, I am an amateur watch repair guy and just aquired one of this for my workbench. Although it was listed as working, I am not getting ant readings of the microphones.Can you tell me what could be the problem? all I am getting on the display is 0F.
SDS1104 Computer Software Not Replicating O-Scope Display - Page 1
Forum section: electronics / testgear

author: Yousoufian
author_rank: Newbie
timestamp: December 17, 2024, 10:53:09 pm
content: I'm trying to use my Vevor SDS1104 o-scope with my computer via USB connection, but for some reason it is not duplicating the scope's screen...So far all the other controls and communications seem to work. I can export waveform data (*.bin) and images of the scope's screen (a little troubleshooting to get them into the correct folder directory path, but nothing amiss with the captures). I can remote control the scope, recall data from the computer, store data to the computer, and replay (Auto Player) data. But for the life of me I can't figure out if the software is supposed to show a replication of the scope's screen, if I set something up wrong, or why everything else works except the screen replication.Any ideas or solutions would be greatly appreciated!So far this forum has helped me greatly prior to me making an account. Love the info about test equipment and the solid reviews given!
Tektronix TLA APPLICATION SOFTWARE / TLAVu - Page 1
Forum section: electronics / testgear

author: EduardGede
author_rank: Newbie
timestamp: December 17, 2024, 05:50:05 am
content: Hi,Does anyone have the:"Tektronix Logic Analyzer Family Application Software Version 4.3" CD's"Tektronix Logic Analyzer Family Application Software Version 4.2" CD'sand or installer packages for !!!!TLA APPLICATION SOFTWARE V4.3 (V4.3.225)TLA APPLICATION SOFTWARE V4.2 (V4.2.112sp1)TLAVu V4.3 (V4.3.225)TLAVu V4.2 (V4.2.112sp1)Gede
upgrading hp 8757D - Page 1
Forum section: electronics / testgear

author: pe2ben
author_rank: Contributor
timestamp: December 15, 2024, 09:15:34 am
content: Hello everone,Is it possible to upgrade my 3 port SNA (a/b/r) to a 4 port SNA by just replace the frontpanel or do in need some other changes?Thanks, Ben

author: ddrl46
author_rank: Regular Contributor
timestamp: December 15, 2024, 10:56:16 am
content: You'll also need an additional log amplifier assembly (A9) in order to add an additional channel as shown in the service manual.I'm not sure if any additional configuration or different firmware is required to get this to work either.

author: pe2ben
author_rank: Contributor
timestamp: December 18, 2024, 03:38:19 pm
content: Thanks, frontpanel okay but somebody know if i have to change the firmware?
Willem EPROM Burner Stopped Working - Page 1
Forum section: electronics / testgear

author: TMA-1
author_rank: Contributor
timestamp: December 15, 2024, 06:04:10 am
content: About a dozen years ago I bought a Willem EPROM Programmer PCB50 Clone. It worked very well for me at the time, though having to use a Windows XP PC to run the software for it is a bit of a hassle.Yesterday I tried to use it for the first time in a couple of years, and ran into problems. (Yes, I still have a desktop that can boot into Windows XP.)The three status lights are all fine until the programmer software loads up. As soon as the software initializes, the VCC & VPP lights go out, and there is no voltage there. (Needless to say any attempted operation fails at that point.)The power lights stay out, unless and until I reboot the PC; when the PC POSTs, those lights come back on. Clearly the programmer's software is triggering something bad with the parallel port, but what?I have tried:checking my DIP switches and jumpers about two dozen times;using either USB or a DC wall-wart as supplementary power;re-capping the Willem board;checking the 7805 (it's fine);every available setting of BIOS parameters related to the parallel port (defaulting to LPT1, ECP type);updating the PCB50 software to the latest;updating the parallel port driver, but "best driver already installed".Anyone have a clue what I'm missing? Is it time to give up on this vintage burner?

author: Messtechniker
author_rank: Frequent Contributor
timestamp: December 15, 2024, 07:16:24 am
content: How about checking the voltages present at the transistors. Might give a clue.

author: pcprogrammer
author_rank: Super Contributor
timestamp: December 15, 2024, 07:49:07 am
content: Or the parallel port of the PC is the culprit.Do you have a scope or simple logic analyzer? If so measure what is going on on the parallel port signals.

author: TMA-1
author_rank: Contributor
timestamp: December 15, 2024, 08:10:03 pm
content: Worthy suggestions both, but it occurred to me that I have another old XP laptop, so I tried that experiment first.It works.So the conclusion is, I have a parallel port on my desktop that is somehow defective. The motherboard is probably right about the correct age to suffer from Bad Caps Disease, too. In any case the Willem is fine, and I'm back in business. Thanks all.

author: optotester
author_rank: Regular Contributor
timestamp: December 16, 2024, 07:57:28 am
content: Probably not what you want to hear but CH341/CH347 costs less than 10€ and have greater compatibility now.Still, if you are able to fix it, you can run it under more recent OS:https://www.jonathandupre.fr/articles/24-logiciel-scripts/166-programmateur-willem-pcb5-0c-windows-64-bits/(in French)
Dho 804 /900 mod - Page 1
Forum section: electronics / testgear

author: click381
author_rank: Newbie
timestamp: December 16, 2024, 02:49:23 am
content: Hi, I just picked up a Dho804 tryig to install the 804/900 mod and I'm not able to get the pull Key.data. The Key data is not on my Dir.Any help would be appreciated. Thanks

author: norbert.kiszka
author_rank: Frequent Contributor
timestamp: December 16, 2024, 02:51:23 am
content: Too lazy to show us command You used and eventual error message?
anyone seen a review of the cheap 100X differential probe from Aliexpress - Page 1
Forum section: electronics / testgear

author: Odd
author_rank: Regular Contributor
timestamp: December 14, 2024, 04:11:06 pm
content: You can easily find them here:https://www.aliexpress.com/w/wholesale-10M-Oscilloscope-Differential-Probe.htmlI am looking for some review/test, a differential probe does not *need* to cost a lot, as there is nothing special inside, and I am curious about this one, how it compares to the well known Micsig and such.

author: xtech
author_rank: Regular Contributor
timestamp: December 14, 2024, 04:22:37 pm
content: That aliexpress diff probe is low voltage one (max 40Vpp). For micsig you have 700Vpp - you pay for your safetyAlso bandwidth is 10x smaller.

author: stj
author_rank: Super Contributor
timestamp: December 14, 2024, 04:27:27 pm
content: it looks risky,i would want a plastic outer housing and plastic or shrouded BNC's incase it accidentally grounds against something!

author: nctnico
author_rank: Super Contributor
timestamp: December 14, 2024, 04:33:17 pm
content: Quote from: Odd on December 14, 2024, 04:11:06 pmThis one is intended to bring small signals into an oscilloscope (hence the 10x and 100x gain). Not for probing high voltages. This doen't make it useless but it just serves an entirely different purpose which makes it not comparable to the high voltage differential probes Micsig makes.

author: kripton2035
author_rank: Super Contributor
timestamp: December 14, 2024, 05:45:32 pm
content: I bought a used high voltage diff probe for almost the price of this new low voltage one...just post alerts on ebay or your local craiglist and be a little patient.

author: egonotto
author_rank: Super Contributor
timestamp: December 14, 2024, 08:21:33 pm
content: Hello,but there is something about it:https://www.eevblog.com/forum/testgear/cheap-chinese-oscilloscope-preamp-tear-downreview-is-it-any-good/msg5712421/#msg5712421https://www.eevblog.com/forum/testgear/t100-1x10x100x-oszilloskop-differentialsonde/msg5732125/#msg5732125https://www.eevblog.com/forum/testgear/review-of-t100-differential-amplifier/msg5627507/#msg5627507Best regardsegonotto

author: nctnico
author_rank: Super Contributor
timestamp: December 14, 2024, 08:48:38 pm
content: Quote from: egonotto on December 14, 2024, 08:21:33 pmThanks for bringing that up! The bottom line is that these devices are crap. Having it battery powered only to completely screw up the noise floor by having a switching PSU inside
Service manual with parts list / schematics for KS 34465/70A - Page 1
Forum section: electronics / testgear

author: Traceless
author_rank: Frequent Contributor
timestamp: December 12, 2024, 10:19:04 pm
content: Hey everyone,are there any parts lists/schematics for the newer Keysight DMMs (34465A/34470A) available? I found aservice manualon xdevs, however unlike the34401A service manualit is missing the parts/schematics section.Currently I'm trying to find the exact type/parts number of the parts marked as:E103 (MOV)Q101, Q102, Q103R102/103/120 (<- package type/power rating)in the bottom left area onthispicture.Also I'd like to verify if I'm correct in assuming that Q41X would be MMBT6520L, and D03 onthispicture could be an MBRS340T3G.

author: coromonadalix
author_rank: Super Contributor
timestamp: December 13, 2024, 01:06:22 pm
content: so far people managed to get parts numbers in other threads, but no schematics beyond the 34410a 11a series have leakedmaybe it has some similarities .... but reverse engineering must be done ...

author: Kleinstein
author_rank: Super Contributor
timestamp: December 13, 2024, 02:22:39 pm
content: For the large resistors R102,R120,.. it is likely about the voltage rating, not so much the power rating. The size could be measured, of needed even from pictures.Q101 to Q104 should be high voltage depl. MOSFETs. There are not that many to choose from. BSS129 would be a first candidate.The MOVs are often labeled and this should be a high voltage type, like close to 1000 V.

author: jc101
author_rank: Frequent Contributor
timestamp: December 13, 2024, 05:15:07 pm
content: This gives some part numbers, but only those deemed user replaceable. I think it may just be an updated version of the link posted by the OP.https://www.keysight.com/us/en/assets/9018-03876/service-manuals/9018-03876.pdf

author: Traceless
author_rank: Frequent Contributor
timestamp: December 14, 2024, 10:04:29 am
content: @Kleinstein: Looking for BSS129 I mostly find thisSiemens Small-Signal Transistor in the TO-92 Package. I didn't get any hits for that type on Digikey, Farnell or Mouser, however there are similar type names in the SOT23-3 package, for instanceBSS126, BSS127.@jc101: Thank you for the link, just like in the manual I linked above there is very little information on individual components present. Basically what is missing is the replacable parts starting atp. 127 in the 34401A manualand ideally the trailing schematics.

author: Kleinstein
author_rank: Super Contributor
timestamp: December 14, 2024, 10:19:03 am
content: The FETs in the protection should be depletion mode. So the BSS126 could be OK but the BSS127 not. The BSS126 could be good enough, a CPC3982 would be a 800 V type and I don't see a high voltage one in SOT23.
Any one using Viavi JDSU JD723/724/725/726 ? - Page 1
Forum section: electronics / testgear

author: smdbg
author_rank: Newbie
timestamp: December 13, 2024, 01:43:31 pm
content: Hi all any one using JD723/724/725/726 ? I was offered one with not working touch screen , and i was wondering if connected mouse to device USB port will work ?! The uncertainty comes from dis that the OS of the device is not Windows . I would appreciate it if anyone can test this.
Fluke 8845A hidden range - Page 1
Forum section: electronics / testgear

author: Miti
author_rank: Super Contributor
timestamp: November 29, 2024, 03:40:02 am
content: I have a Fluke 8845A for awhile, it was defective at work, the calibration company quoted a ridiculous amount to replace the board, was declared scrap.The issue was an intermittent inguard/outguard IR LED, I replaced it and it works well for years... but, the 100 and 1000V ranges were reading a bit low so I gave up on it as the calibration quote was too high.Now that I have 4 wires shorts I plugged one into the input, I left it ON for few hours and, sure enough, the 100V and 1000V ranges had a negative offset.I decided to do a zero adjustment as per the calibration manual and, wow, I think it is bang on now on all ranges, compared with a recently calibrated 34401A. Moreover, even though it is a 8845A and should not have a 10 Ohm range, it does show up during zero calibration and goes away after power cycle.1. Does anyone know if it is possible to call that range somehow, or to hack it?2. Does anybody have an application to run the calibration program listed at the end of the calibration manual from a GUI?Cheers,Miti

author: coromonadalix
author_rank: Super Contributor
timestamp: November 29, 2024, 04:46:38 am
content: your best luck would be to poke in their firmwares 8845 8846 and see their differences and function calls ...i never found out their fw files ... you have their tektronix equivalent DMM4050 and DMM4040 i think

author: Miti
author_rank: Super Contributor
timestamp: December 13, 2024, 03:21:16 am
content: If only I knew how to do that...
SDS1202X-E   The External connector usage - Page 1
Forum section: electronics / testgear

author: Don Warr
author_rank: Newbie
timestamp: December 11, 2024, 12:14:40 am
content: Can't find any data on this models input connector "EXT".... I know what a external trigger is suppose to do... But on this oscilloscope I seem to get a screen trace when I have set triggering to EXT with no or shorted "EXT" input... What type of signal should be applied, Square, Ramp, Circle what?What should the "EXT" input amplitude be, 100mv , 1V, 10Kv ...??Any input into this would be appreciated .... Thanks

author: noisyee
author_rank: Contributor
timestamp: December 11, 2024, 01:35:00 am
content: The EXT has specification in the datasheet.QuoteFor example, if you want to use EXT for trigger, you should feed at least 200mVpp signal from DC (maybe they mean very very low frequency, not real DC) to 10MHz, or 300mVpp for 10MHz above, for stable trigger. You can feed no more than absolute maximum voltage (forgot where this specs are, should be the same as channel input) into this port, but out side ±0.6V range can not be triggered.In theory, any waveform is OK, in practice, square wave will have the best trigger performance. The higher the slew rate is, the better.

author: Don Warr
author_rank: Newbie
timestamp: December 11, 2024, 09:45:04 am
content: Well thank you noisyee for the quick response,,,, But Don't you think that I should NOT see a trace if ext trigger is selected and input is 0v (shorted)..Helping others, helps get you into Heaven, lol....

author: tautech
author_rank: Super Contributor
timestamp: December 11, 2024, 10:56:54 am
content: Quote from: Don Warr on December 11, 2024, 09:45:04 amIn Auto triggering mode a trace is always visible.Maybe get to know some of the other Trigger modes and types.What exactly is your Ext trigger requirement ?

author: Don Warr
author_rank: Newbie
timestamp: December 12, 2024, 09:41:16 am
content: Well, thank you ALL for the support... Once you said "Auto = trace, -- Normal = no trace" I was able to track down the cause, which was the coax EXE coming out, although shorted at end, was still picking up random noise... This model is vary sensitive...I will move my Lab to the top of some mountain and everything will be fine... I have had a scope since I was 16 but the digital versions can confuse a 73 year old....

author: tautech
author_rank: Super Contributor
timestamp: December 12, 2024, 10:00:28 am
content: Quote from: Don Warr on December 12, 2024, 09:41:16 amWelcome to the new world to you of sensitive DSO's.

author: BILLPOD
author_rank: Frequent Contributor
timestamp: December 12, 2024, 06:59:39 pm
content: I agree with Don, the menus buried in menus, buried in menus, borders on cruelty for us septuagenarians.
Agilent N9320A TG3 option activation - Page 1
Forum section: electronics / testgear

author: mzj
author_rank: Newbie
timestamp: December 13, 2024, 10:52:21 pm
content: Hi!I bought two N9320A used spectrum analyzers. One had a TG3 option installed, unfortunately, this unit has defective control module and doesn't work at all. I want to move TG3 option to working machine and, of course, I hit a wall with lack of license key. I did some research (on the forum too) and I didn't found any working solution for this.My question is: do you know any generator/method of generation license key for this machine? Even if I read a FLASH memory from original host the key will not work in new machine.The hostID of this machine is07170099, S/N CN0163000400.
Agilent 11974-60028 Mini Teardown - Page 1
Forum section: electronics / testgear

author: gamalot
author_rank: Super Contributor
timestamp: March 20, 2023, 02:47:29 pm
content: You may wonder what the hell Agilent 11974-60028 is, and yes, this was also my question. The documentation on the Keysight website won't tell you the details, I bought it from ebay for AU$70 just to see what's inside, and taking it apart was the only way to know.It is just a 3-rail linear regulated power supply in a box made of aluminum alloy skeletons and sheets.The small transformer and 7815/7915 are used for ±15V/0.2A output, the large transformer, LM723, and two TO-3 power transistors are used for 50V/0.6A output.Nothing fancy, I'll probably use this box for a DIY project or something.

author: guagg
author_rank: Newbie
timestamp: December 11, 2024, 07:42:07 am
content: I have a 11974A but without 11974-60028.do you know the DB9 pin definition.maybe i can power up my 11974.Thacks

author: coromonadalix
author_rank: Super Contributor
timestamp: December 11, 2024, 12:14:25 pm
content: should be easy to find since it is the psu's outputs ....ok it's a frame containing lambda psu's lm723 or fixed ones or similar ...thks for the teardown
Tektronix AFG3022b Arb Gen: password recovery? - Page 1
Forum section: electronics / testgear

author: mr ed
author_rank: Regular Contributor
timestamp: December 10, 2024, 11:12:31 pm
content: The manual says that if the password /lock is lost the unit must be returned to Tektronix.I figure there is a easy but hidden procedure built in to clear an unknown pw.Maybe its to use the SECURE function which sanitizes memory (i.e. military)Maybe a pin held to ground at power up?I'm not stuck but curious ... just in case...
USB to GPIB  Controller for Use with Tektronix TDS3000-series Oscilloscopes - Page 1
Forum section: electronics / testgear

author: whipaway
author_rank: Contributor
timestamp: December 10, 2024, 10:15:37 pm
content: Has anyone used the UGPlus USB to GPIB Controller with the Tektronix TDS3000-seies 'scopes, using the TGDS3GM plug-in module?I want to get the UGPlus so that I can upgrade several 'scopes that I have to higher bandwidths.This is the device that I am thinking of buying:https://www.ebay.com/itm/172082405115?_skw=usb+to+gpib&epid=1776118937&itmmeta=01JES9RF2CJ1J8P4P9AYDY84VN&hash=item2810e91efb:g:wpYAAOSwRQlXeez3&itmprp=enc%3AAQAJAAAA0HoV3kP08IDx%2BKZ9MfhVJKnquEh45HH72jsI3PC%2BGHa5tGI8WBsjBPzVz81C08tFfY58eja0a4LgiYa%2B8IImiVvSp83Qii5F58tqficNDgU0zOcoRdgpy8Hf0%2BduHF4TDZEXfLcU40bZu6c5G7l9kXV3%2FEsWt87boq5QIb0Pl9O5ITecrb1BrBtcwSFxzC2m7kIC0QaoNu7ZmvAuAStftNnGSAKDcD2dIXsL8WawxKNOpT%2B3rGvQIGLwr%2FX932YFPRr6gcMGo5%2FLgZC805JVr2s%3D%7Ctkp%3ABk9SR6Lx4an2ZA
EPROM image for the Wiltorn 6659a sweeper - Page 1
Forum section: electronics / testgear

author: hafrse
author_rank: Regular Contributor
timestamp: December 11, 2024, 07:45:59 am
content: Hello,I have a dead U5 Ver. 7 2716 EPROM and I am looking for a bin image , any help will be appreciatedGeorge
Keysight 33600A Waveform Generator. Self test error - Page 1
Forum section: electronics / testgear

author: Ugur
author_rank: Regular Contributor
timestamp: December 11, 2024, 05:20:31 am
content: Hello,I have a faulty Keysight 33600A Waveform Generator. I am sharing the error codes. Does anyone have experience with this error? Or can I find a service manual?
Teledyne T3DSO2304 Oscilloscope Question  - Page 1
Forum section: electronics / testgear

author: Robbdoe1
author_rank: Contributor
timestamp: December 09, 2024, 05:22:35 pm
content: We have a very nice 300MHz 2GSa/s scope at work. TMI came to calibrate it as they do annually. They weren’t able to as the Zoom/ S-nS switch/encoder was broken. The switch was locked up and some gorilla here broke the knob shaft off.I need a new switch. This one is made by LJV. It has 3 pins on the bottom, 2 pins on the top and 1 pin on each side. I have attached pictures. The board with 14 switches/encoders is made by Siglent. I reached out to them but they are unable to help. I have also reached out to Teledyne and I’m awaiting a response.If anyone can identify this part I would appreciate it greatly. Thanks.

author: tautech
author_rank: Super Contributor
timestamp: December 09, 2024, 09:24:15 pm
content: Looks like a SDS2000X model.Timebase encoder......detented and press to select IIRC.Probably the same as used in the later SDS2000X Plus models.You might find the info you seek in one of the threads here.....

author: Robbdoe1
author_rank: Contributor
timestamp: December 09, 2024, 10:48:00 pm
content: Quote from: tautech on December 09, 2024, 09:24:15 pmI found what appears to be a direct replacement on DigiKey. I had to pull it apart to get the PPR number. Hopefully it works as it’s a real nice scope. Thanks for your help. I appreciate it.
Siglent SDS1104X-E - 2Gs/s on one CH, it's possible ? - Page 1
Forum section: electronics / testgear

author: kermu
author_rank: Newbie
timestamp: December 09, 2024, 04:31:29 pm
content: It's possible to achieve on one channel, in Siglent DSO SDS1104X-E,effective realtime sampling 2 Gsa/s, in interleave mode sampling ?User manual says on site 38: "The maximum sample rate of the oscilloscope is 2 Gsa/s."Krzysztof

author: tautech
author_rank: Super Contributor
timestamp: December 09, 2024, 09:49:22 pm
content: Not possible.Manual error.These do use 2x 1GSa/s ADC's but they are not configured to provide 2 GSa/s on a single channel.All channels active provides 500 MSa/s.

author: kermu
author_rank: Newbie
timestamp: December 09, 2024, 10:03:09 pm
content: This info: "2x1Gsa/s If group A and B only one channel in use"fromhttps://www.eevblog.com/forum/testgear/siglent-sds1204x-e-released-for-domestic-markets-in-china/is invalid ?

author: tautech
author_rank: Super Contributor
timestamp: December 09, 2024, 10:05:42 pm
content: Quote from: kermu on December 09, 2024, 10:03:09 pmNo.It is very correct.

author: kermu
author_rank: Newbie
timestamp: December 09, 2024, 10:20:03 pm
content: O.K.So interlaced sampling (2Gs/s) is not possible, only 2 x 1Gs/s if only one channel of each grup A and B is in use.

author: tautech
author_rank: Super Contributor
timestamp: December 09, 2024, 10:24:12 pm
content: Quote from: kermu on December 09, 2024, 10:20:03 pmExactly.
Siglent SDG2082X waveform gen harmonic feature - Page 1
Forum section: electronics / testgear

author: Conrad Hoffman
author_rank: Super Contributor
timestamp: December 09, 2024, 07:08:41 pm
content: Maybe this has been mentioned but I wanted to point it out. I got the 2082 as that seems to be a sweet spot on performance vs. price. It's 80 MHz. I wondered if one could use the harmonic feature to get signals above 80 MHz, but the answer is no. If you turn on harmonics, the base frequency is limited such that the harmonics don't exceed 80 MHz, even though the signal path certainly exceeds that. Yes, I could hack the firmware, but I choose not to do that. What I'll also try is a simple frequency doubler on the output, nothing more than a small balun and a couple schottky diodes.

author: mawyatt
author_rank: Super Contributor
timestamp: December 09, 2024, 07:59:52 pm
content: If you want to cover a wide frequency range this circuit might prove useful with faster transistors than 2N3904s. We used it at MMW with SiGe devices.https://www.eevblog.com/forum/projects/interesting-differential-inputoutput-transistor-circuit/Best
Metrahit Tech M243A firmware - Page 1
Forum section: electronics / testgear

author: edisitaru
author_rank: Contributor
timestamp: December 06, 2024, 02:02:19 pm
content: HelloI'm looking for firmware v3.06 for Metrahit Tech M243A. Please if anyone has it, post it here.Thanks in advance!

author: coromonadalix
author_rank: Super Contributor
timestamp: December 06, 2024, 03:30:13 pm
content: no fw have ever leaked ... old or new generationno schematics either, unless some one has an updated meter and rip it / dump it ... with jtag tools or others ... if it is possible ?have you asked gossen ??those are 12 k counts made with a maxim asic, if i recall ?what is this meter problem ?

author: edisitaru
author_rank: Contributor
timestamp: December 07, 2024, 08:31:24 am
content: The multimeter is the first generation, Metrahit Tech M243A.It currently has firmware 2.73, no problems, but I would like to upgrade it to the latest version, v3.06.

author: coromonadalix
author_rank: Super Contributor
timestamp: December 07, 2024, 02:15:15 pm
content: ask gossen, i never saw any fw made available ... unless you send the meter to them for repairs and calibration. And they dont support the old metrahit line anymore ...in usa you have gossen usa / dranetz, and they charge hefty price for repairs / calibrations
Micsig DP10007 vs DP10013 - Page 1
Forum section: electronics / testgear

author: aneevuser
author_rank: Frequent Contributor
timestamp: July 23, 2022, 01:05:04 pm
content: I've never used a differential scope probe before, and I'm wondering what are the pros and cons of the Micsig DP10007 as opposed to the DP10013.I want to make (single phase) 230V AC measurements and also low voltage (say up to 20V) differential measurements on low power circuits.The maximum differential voltage for both models seems fine for 230V AC (700V for DP10007, 1300V for DP10013), but the low range attentuation of the DP10007 seems to my mind to be more suitable for low voltage differential measurements (DP10007 is x10, DP10013 is x50) - I'm wondering if low voltage measurements using the DP10013 will have a noticeably worse SNR, given the increased attenuation.Both probes are the same price in the UK, so that isn't a consideration.The only advantage I can think of for the DP10013 is that it may survive high voltage transients that kill the other model, but I'm not sure if these occur often enough to be a concern.So: are my concerns above a valid reason to go for the DP10007 over the DP10013?

author: Noy
author_rank: Frequent Contributor
timestamp: July 23, 2022, 07:56:33 pm
content: You shouldnt forget that often modern power supplys are using active PFCsand than 500-700V is possible inside these devices.I would take DP10013 and be on a safe harbour for my scope...

author: bdunham7
author_rank: Super Contributor
timestamp: July 23, 2022, 08:55:42 pm
content: The DP10007 won't blow up at 701 volts, it simply clips. It is protected to much higher voltages. I don't know if the DP10013 is actually any more robust, but it might be since it has a higher input impedance and higher CAT rating. The DP10007 has an output of +/- 7V, but the DP10013 is only +/- 3V. Neither is ideal, IMO. 20X/200X w/ +/- 7V would actually be what I'd prefer. That said, either one will work safely for your application and you can look at the noise specs here. Keep in mind that the BW and CMRR specs may be a bit optimistic.https://www.micsig.com/Differential%20Probe04/

author: aneevuser
author_rank: Frequent Contributor
timestamp: July 24, 2022, 11:37:36 am
content: Thanks for the replies.I've decided that, in order to avoid my standard 6 months of analysis paralysis and general indecision over a fairly trivial purchase, it'll be the DP10007.

author: Proxy64
author_rank: Regular Contributor
timestamp: November 16, 2024, 12:45:03 pm
content: Hi, I think the DP1007 is a good choice for smps repair (enough and upgradable).Did you get it ?Could you give us a little review ? Thank you

author: MF-jockey
author_rank: Regular Contributor
timestamp: December 06, 2024, 11:12:11 pm
content: The old DP10007 with damping factor 10x/100x will hardly be available anymore, see this thread:https://www.eevblog.com/forum/testgear/new-eevblog-hv-probe/msg5697311/#msg5697311
HMP4040 Schematic - Page 1
Forum section: electronics / testgear

author: Murphy86
author_rank: Newbie
timestamp: December 04, 2024, 03:37:35 pm
content: I run small business assembling and maintaining ATS (automated test systems).Goten quite few RMA-s of failing HMP4040 PSU-s. Some are under warranty some too old for that.I have excluded AC side issues as some older systems have Agilent A66000A and they have ZERO issues regarless of age.Failing channel(s) differ but its always LTC3703 circuit that seems to be pre regulator before linear stage.R&S wont respond ofc, allready complained about low quality screw terminals at back(they sometimes wont give connection even if wire is tight under screw) but no response.Hoping with schematic i could maybe find out design issue and maybe replace parts with different(say example mosfet ratings are designed too close to failure).PSU is never run close to capacity, usual loads are, under 5V and 2A(unless DUT has fault). So overheating etc is not an issue.

author: coromonadalix
author_rank: Super Contributor
timestamp: December 04, 2024, 05:28:01 pm
content: thread w pictureshttps://www.eevblog.com/forum/metrology/hmp4040-calibration-and-adjustment/

author: Harry_22
author_rank: Frequent Contributor
timestamp: December 04, 2024, 05:44:44 pm
content: Hi!Let us see the behaviour of several HMP.Only two pictures each. Switched off outputs and switched on.

author: Murphy86
author_rank: Newbie
timestamp: December 05, 2024, 07:10:44 am
content: Sadly have no picture/video to offer for symptoms.have one in RMA at the moment, that one is waiting parts(correspondig channel removed). But symptom is output on no voltage at output.Diagnosos: 2x 7A fuses in channel AC input will blow and atleast one mosfet will be dead.Transformer measured 44VAC(should be around 61VDC after bridge) and mosfets are 100V(IPD180N10N), it should be fine. Yet they burn.Only thing i can think of is in ATS outputs are turned on and off many times. Probably over thousands of times per day. But i mean, its LAB PSU its expected to have this use.

author: Harry_22
author_rank: Frequent Contributor
timestamp: December 05, 2024, 10:16:39 am
content: When you solder fuses hold them with tweezers all the time.Even the original ones can swell.
EMONA Instrument AU offline? - Page 1
Forum section: electronics / testgear

author: Odd-Job
author_rank: Unknown
timestamp: December 06, 2024, 07:18:36 am
content: Was looking to start some new TE pricing today, tried logging into Acc and general front page ofhttps://emona.com.au/Just received the followingHmm. We’re having trouble finding that site.We can’t connect to the server at emona.com.au.If you entered the right address, you can:Try again laterCheck your network connectionCheck that Firefox has permission to access the web (you might be connected but behind a firewall)Anyone else?

author: Muttley Snickers
author_rank: Unknown
timestamp: December 06, 2024, 07:39:53 am
content: Quote from: Odd-Job on December 06, 2024, 07:18:36 amIt works fine from my TV browser, pages were a bit slow to load though.

author: ToThePub
author_rank: Contributor
timestamp: December 06, 2024, 08:06:58 am
content: If they had a problem, they don't now. Site's up for me.

author: indeterminate
author_rank: Regular Contributor
timestamp: December 06, 2024, 08:07:53 am
content: Working fine heartry a ipconfig /flushdns in a cmd box
Fenlow 705 nixie tube multimeter - Page 1
Forum section: electronics / testgear

author: PureZX
author_rank: Newbie
timestamp: November 18, 2023, 06:36:30 pm
content: HelloI recently got hold of a nixie tube multimeter manufactured by Fenlow Electronics Ltd of Jessamy Road, Weybridge, Surrey. It works, and is surprisingly accurate, however, the polarity nixie is not working. Before investigating the problem I attempted to find some data on the meter, but I can't find anything. Has anyone got any data on the Fenlow 705, user manual, schematics and/or calibration data would be a great help.Thanks

author: factory
author_rank: Super Contributor
timestamp: November 20, 2023, 09:27:45 pm
content: Does the symbol bulb have the sine-wave & ohms symbols, as well as the polarity +/-? and are they connected? If yes, do they work with the function switch in AC & ohms?David

author: PureZX
author_rank: Newbie
timestamp: November 20, 2023, 11:35:57 pm
content: Hello David,No, it can only display + or -.Mike

author: factory
author_rank: Super Contributor
timestamp: December 05, 2024, 10:10:58 pm
content: Could this be the same one, that I acquired recently?First things were to work out why the symbol bulb was not displaying anything, this wasn't too hard, it was very dead, voltage was present on two of the pins. Removing the bulb & checking it with a Megger confirmed it was dead, no signs of life, not even at higher voltages.Thankfully I had one of these, bought unknowingly from a TE murderer in Penkridge, fitting this I now had a minus symbol and an AC symbol. Next problem was the minus symbol was stuck on in all modes, even with a positive input.I've worked out some of the circuit, 3 transistors near the bulb deal with switching the +/- symbols and the AC symbol is switched by another transistor found near the mode switch.Eventually I traced the +/ toggle back to some Nand gates, one was stuck high on both inputs & outputs.Replacing that 7400 got the symbols lighting one at a time, but with another fault where + or - was staying on in ohms mode.I believe two more transistors near the range switch, should turn off the +/- symbols when in ohms mode, this is where I've got to with the repair ATM.David
Siglent 1104X-E ground noise - Page 1
Forum section: electronics / testgear

author: 1audio
author_rank: Frequent Contributor
timestamp: December 01, 2024, 06:25:50 am
content: I have an 1104X-E which mostly works great. However since a lot of what I do involves looking at low level signals I have a constant problem with this instrument- Pretty much whenever The DUT is grounded I have a high broad noise floor that messes with any trace below several volts. I did some careful checking and I'm getting about 25 mV of 50 KHz spikes between the scope ground and everything on my bench. Is this switching supply leakage? Does anyone else have this issue? Any advice would be appreciated.

author: tautech
author_rank: Super Contributor
timestamp: December 01, 2024, 07:00:38 am
content: Quote from: 1audio on December 01, 2024, 06:25:50 amMost likely but not from the scope.Your task is to find where the interference is coming from.Screenshots as evidence please.

author: Kean
author_rank: Unknown
timestamp: December 01, 2024, 09:15:01 am
content: That sound like interference from a nearby SMPS. The most common cause mentioned here is LED lighting.Try turning other things on/off in a systematic way to identify the source.

author: 1audio
author_rank: Frequent Contributor
timestamp: December 01, 2024, 06:50:00 pm
content: I just checked and the power ground the scope is on is 10 Ohms from the power ground the rest of the instruments are on. I have some power distribution checking to do before locating noise sources (I have lots).

author: 1audio
author_rank: Frequent Contributor
timestamp: December 05, 2024, 01:37:58 am
content: Thee real issue it turns out is intermittent connection in the probe shield at the BNC end. A small tug in the wrong direction and its open. Need connecting is 10 Ohms or more. All 4 probes show this problem. If I switched to a tek or HP probe the noise is much lower. Has anyone else had this issue with Siglent probes?

author: Calambres
author_rank: Frequent Contributor
timestamp: December 05, 2024, 04:26:40 pm
content: Quote from: 1audio on December 05, 2024, 01:37:58 amNope! All the 4 probes for my 1104X-E work fine, 'though I must say that one of them was warranty exchanged because the 1x-10x switch was not working properly.
Sds800x missing software options  - Page 1
Forum section: electronics / testgear

author: CrabApple
author_rank: Newbie
timestamp: December 05, 2024, 05:40:08 am
content: Hello all,I'm a bit confused about my new SDS804X HD. When I go to software options I see the 30 remaining trials of the SDS800XHD-PA. But that is literally the only option type available to me. I thought there were a plethora of potential upgrade options I could eventually use, but now I'm worried I'm limited because I went with the cheapest 4 port option.Am I missing something obvious?Thanks in advance everyone.Also I picked up a SDG wave form generator and was wondering if there's a way to hook them together to where the oscope can control it in some capacity, not necessary really just curious. I thought there was an option to turn on a wave Gen within the oscope but again I've only got the power analyzer option available to purchase.73,CrabApps

author: hp lee
author_rank: Newbie
timestamp: December 05, 2024, 05:48:22 am
content: https://siglentna.com/wp-content/uploads/dlm_uploads/2024/06/sds800x-hd-firmware-revise-history-and-update-instructions.pdf3. Standard software functions of FG and LA.'AWG' and 'MSO' license is now standard. no need to activate it.

author: tautech
author_rank: Super Contributor
timestamp: December 05, 2024, 05:57:34 am
content: Quote from: CrabApple on December 05, 2024, 05:40:08 amThere were only 3 at release and as member hp lee points out, with latest firmware there is now just one.Quote from: CrabApple on December 05, 2024, 05:40:08 amThe only FG/AWG the scope can directly control is the USB module SAG1021I and IMO you made the better choice getting a SDG to pair with it.In Bode plot mode the scope takes control of SDG models to provide the stimulus waveforms for FRA.You can read lots about FRA capabilities here, albeit with the SDS**04X-E models:https://www.eevblog.com/forum/testgear/siglent-sds1x04x-e-bodeplot-ii-(sfra)-features-and-testing-(coming)/

author: CrabApple
author_rank: Newbie
timestamp: December 05, 2024, 06:14:09 am
content: Thank you both so much! That put my mind at ease. My wife is buying me the logic analyzer for an Xmas gift for me and I was worried I wouldn't be able to use it. Would you recommend a third party logic analyzer like I did with the wave Gen or is the add on plenty good enough?Out of curiosity, is the developer password available somewhere or does it need to be reverse engineered? I'm a big fan of having full control of my hardware that I paid for.

author: tautech
author_rank: Super Contributor
timestamp: December 05, 2024, 06:47:51 am
content: Quote from: CrabApple on December 05, 2024, 06:14:09 amSPL1016 is perfectly fine for basic LA needs.QuoteNot for public release however someone may share it with you via a PM.

author: CrabApple
author_rank: Newbie
timestamp: December 05, 2024, 07:06:42 am
content: Awesome. Now I can't wait for Xmas for the first time in years haha!
Data I/O 29B program modules. - Page 1
Forum section: electronics / testgear

author: Tom Swift
author_rank: Contributor
timestamp: December 05, 2024, 12:35:48 am
content: I told a friend that I would be able to burn a 27C400 with my Data I/O 29B. I get the EPROMs and saw a problem. These are 40pin EPROMs. Oops.I have a UniPak 2B, 2 LogicPaks, a 303A-002 and a 303A-100, (no idea what this does).I also have a socket adapter DATA I/O 351A-070 that'll accept a 24pin socket and has a 40pin ZIF socket output. Would I need a DATA I/O 351B-068 24pin module for this adapter? Also, could I also use a DATA I/O 351B-095 40pin ZIF socket module to program this EPROM?Finding documentation on this is like pulling teeth... or maybe my Google-fu is terrible. Any help would be great.Thanks!
Keithley 595 Quasistatic CV Meter - Page 1
Forum section: electronics / testgear

author: Rax
author_rank: Super Contributor
timestamp: October 06, 2022, 02:45:08 pm
content: Hi all,I recently got this alongside a batch of other equipment I am familiar with, but this one I have no idea what it's useful for. It seems to measure capacitance in a pretty limited range, and current?...Anyone willing to throw some light for me on this, I'd appreciate it.Thanks a bunch!

author: alm
author_rank: Super Contributor
timestamp: October 06, 2022, 10:23:19 pm
content: I've never used one. From what I know, they were designed to do measurements as would be done in semiconductor fabs, like verifying processes. As for what a hobbyist could use it for, I guess as a limited voltage source that can do steps and square waves, and ammeter. It goes down to 20 pA full scale with 1 fA resolution. So it's probably quite good as a high resistance meter: 20 V / 20 pA gives 1 TOhm full scale, with a resolution (surely down in the noise) of 1 POhm.I don't know how useful a "quasistatic C-V curve" is outside semiconductor device testing.Maybe it could be used to trace I-V curves, like a two terminal curve tracer?

author: ch_scr
author_rank: Frequent Contributor
timestamp: October 07, 2022, 07:31:17 am
content: Here Sam Zeloof explains and shows it:,but the short of it is: It's a precise capacitance meter with low ranges and integrated, adjustable / sweep-able bias voltage.Excels at measuring varicap diodes and parasitic device characteristics that behave similar. You could also e.g. measure the reduction in capacitance of non-NP0 SMD cap's under bias voltage.

author: Smokey
author_rank: Super Contributor
timestamp: December 05, 2024, 01:35:53 am
content: That youtube video is amazing.That dude's lab has crazy, high end, super specialized equipment right next to a $10 vichy meter and other random amazon style power supplies...
Keithley 138 multimeter?? - Page 1
Forum section: electronics / testgear

author: inse
author_rank: Super Contributor
timestamp: December 02, 2024, 10:46:20 pm
content: Anyone seen this piece of equipment before?Doesn‘t look like Keithley, no reference found either.Picture taken from advertisment

author: Sensorcat
author_rank: Regular Contributor
timestamp: December 02, 2024, 11:40:06 pm
content: That's an "Escort EDM-89S", probably sold under other brand names also. Search forCode:EDM-89S dmmto avoid lots of cars in the results and look at the images.It seems unlikely that Keithley offered a rebadged version of this chinese DMM or that they sold a design to china. But someone was either good at photoshop or printing the case nicely

author: AVGresponding
author_rank: Super Contributor
timestamp: December 03, 2024, 06:17:33 am
content: It's notcompletelyunbelievable; the Agilent U1401 is a rebadged Escort 2030, and I think maybe some of the Tektronix DMM's were made by Escort

author: inse
author_rank: Super Contributor
timestamp: December 03, 2024, 06:26:50 am
content: Strangely, it’s not known on the Tek website where they keep records of even the oldest Keithley gear…

author: coromonadalix
author_rank: Super Contributor
timestamp: December 03, 2024, 11:05:46 am
content: maybe this one is an exception too ?