hybridfree/eevblog-posts huggingface dataset:
VFO Frequency Check - Page 1
Forum section: electronics / testgear

author: ko4nrbs
author_rank: Regular Contributor
timestamp: November 07, 2022, 06:37:51 pm
content: If using this counter, what do I need in order to check the frequency on an old Heathkit HG-10 VFO? Its output is 5 volts RMS.The counter:https://usa.banggood.com/1Hz-50MHz-High-Sensitivity-Frequency-Meter-Counter-Measurement-Tester-Module-7V-9V-50mA-p-1662557.html?cur_warehouse=CNThank you,Bill

author: Grandchuck
author_rank: Super Contributor
timestamp: November 07, 2022, 09:32:47 pm
content: Do you have an oscilloscope probe?

author: ko4nrbs
author_rank: Regular Contributor
timestamp: November 07, 2022, 10:25:31 pm
content: Yes, I do. I wanted to use this and keep it on while operating so I can constantly monitor my frequency.Bill

author: David Hess
author_rank: Super Contributor
timestamp: November 08, 2022, 02:51:30 am
content: What I would do, and what I have done in the past, is hand wire a JFET or bipolar transistor follower into the oscillator to drive a coaxial transmission line going to the frequency counter.

author: Swainster
author_rank: Frequent Contributor
timestamp: November 08, 2022, 10:00:23 am
content: This is probably one of many "clones" of the pic based counter by DL4YHFhttps://www.qsl.net/dl4yhf/freq_counter/freq_counter.html. If so, you will need to turn off the power saving mode (it may be off by default - I think it was off on mine). You can find the manual athttps://www.qrpproject.de/UK/DL4YHFcounter.html. Watch out for any preprogrammed offset - if you dont realise it is there then it can cause a lot of head scratching.

author: colorado.rob
author_rank: Frequent Contributor
timestamp: November 08, 2022, 05:52:47 pm
content: Most DSOs -- even the inexpensive ones -- have a cymometer that will be more accurate & precise than that frequency counter.

author: Hexley
author_rank: Regular Contributor
timestamp: November 08, 2022, 06:23:50 pm
content: Quote from: ko4nrbs on November 07, 2022, 10:25:31 pmQuote from: David Hess on November 08, 2022, 02:51:30 amIf you add a buffer like David Hess suggests (an excellent idea), it might be a good idea to control it with the transmit (PTT) line, or from the spot switch if your rig has one.Otherwise you run a risk of leakage from the VFO-to-counter cable, which will be carrying a CW signal at your operating signal even while you are receiving.
Voltech PM1000+ or Tektronix PA1000+ - Page 1
Forum section: electronics / testgear

author: coppice
author_rank: Super Contributor
timestamp: November 07, 2022, 04:08:32 pm
content: Does anyone else here have or use a Voltech PM1000+ or Tektronix PA1000+ power analyser? I've had the Voltech version for a while, and used it for various things, but only today have I tried to use its graphing functions. I am confused by them.The menus allow 3 types of graph - waveform (instantaneous values, graphed like an oscilloscope), harmonic bar chart, and integration. I want to graph the power consumption of something as it varies over time. I need to select integration mode and integration graphing for this, set an X and a Y axis scale, and start the measurement. I set Y to 200W full scale, and X to 90 minutes full scale. When I start the measurement I see a yellow line form across the screen over about one minute, tracing out the power consumption of my load. Once this reaches the right side of the screen nothing more seems to happen. Why isn't it taking 90 minutes to draw this line? I can't find anything else related to graphing which I need to select.

author: threephase
author_rank: Regular Contributor
timestamp: November 08, 2022, 05:20:13 pm
content: I have a PA1000, but in the integration graph I do not have a setting for the x axis, only the Y axis.In the integrator mode setup I do have a clock duration setting at 60 minutes default.With either the default setting or setting it to 90 minutes the initial graph displayed is 1 minute, then as the line reaches the right hand side of the graph the display is automatically updated and changes the x axis to a 10 minute duration.In the top left hand corner of the screen there is a Time Set value that updates to '0.02 h' as the graph display is changed and then continues to update as further data is collected.At 10 minutes the graph again updates automatically and the x axis goes to 1 hour.Hope the above helps.
HP 120b - Vertical vernier affects position - Page 1
Forum section: electronics / testgear

author: deafen
author_rank: Contributor
timestamp: September 08, 2022, 01:06:49 pm
content: I just picked this up on FBM, and after some contact cleaner, it's working okay - clean/bright/sharp trace, controls all work, etc. Enough to tell me that it's worth fully fixing up.It's got one real functional issue. Adjusting the vertical amplitude via the vernier expands the trace as expected, but also moves the trace's position.It's a pretty complex three-stage differential setup, with direct coupling and cross-coupled plate-grid feedback. The service manual just says to investigate the vertical amplifier ... Uh, thanks I guess? I know my common-cathode stuff, but not a lot about differential amplifiers. The 12AU7s test a little weak, but still serviceable (and I don't have any spares on hand anyway).Before I dive into thoroughly analyzing the circuit, any quick ideas I should try?(I'll also mention that vertical sensitivity isn't great, and LF response isn't that hot either. The calibration trace is awfully slopey. I suspect these are all related issues.)

author: TimFox
author_rank: Super Contributor
timestamp: September 08, 2022, 02:00:52 pm
content: Have you tried adjusting the balance trim/control R16? The usual method on older oscilloscopes is to adjust it until there is no change in the trace position when changing vertical gain.

author: deafen
author_rank: Contributor
timestamp: September 08, 2022, 02:51:36 pm
content: Quote from: TimFox on September 08, 2022, 02:00:52 pmI haven't, but I will. The description of R16 isn't explicit that it impacts trace position, so I missed that. Thanks, I'll try that tonight!

author: deafen
author_rank: Contributor
timestamp: November 07, 2022, 07:43:54 pm
content: Just following up on this - yep, tweaking R16 fixed it right up! Of course, I didn't realize that R16 is the "BAL" control on the front panel until I had pulled it from my shelf and opened it upI discovered that the "bad vertical sensitivity" issue was because someone had taken off the vert and horiz knobs and put them back on incorrectly, so that the vert was off by one position (i.e., it was on 10V/div when it looked like 1V/div) and the horiz was off by four positions. THAT got fixed for sure.Ran it through a basic calibration and it looks good to go. Not even seeing any power supply ripple, which is a relief - that's a LOT of filter caps to replace!
Hantek 5102P Upgraded to 200mghz how do i test this? - Page 1
Forum section: electronics / testgear

author: Gazmon
author_rank: Regular Contributor
timestamp: November 07, 2022, 06:24:44 pm
content: Hi all,As the title explains, followed to the upgrade process, seems all ok, how's the easiest way to hook something up to see if it has worked correctly pleaseAs nowhere in the system settings does it say , any tips??Cheers Gary
EEVBlog Discount at TME? - Page 1
Forum section: electronics / testgear

author: Stiletto
author_rank: Contributor
timestamp: July 10, 2022, 11:09:13 pm
content: I've been reading through the forum posts about good values in multimeters this weekend, and considering ordering a Brymen 869S from TME. Somewhere, I recall reading that EEVBlog had a discount with them. Is that still the case, and is there a code or something I need to take advantage of it, like we do with Tequipment? If so, I'd appreciate if someone could PM it to me.Thanks!

author: arvidb
author_rank: Newbie
timestamp: November 07, 2022, 06:09:30 am
content: Same here, I'm also looking for a discount code for TME, if there is one. Thanks!
Frequency Counter Input Buffer - Page 1
Forum section: electronics / testgear

author: ko4nrbs
author_rank: Regular Contributor
timestamp: November 05, 2022, 01:39:38 pm
content: Any suggestions for a buffer for this counter?https://usa.banggood.com/1Hz-50MHz-High-Sensitivity-Frequency-Meter-Counter-Measurement-Tester-Module-7V-9V-50mA-p-1662557.html?cur_warehouse=CNI tried a pickup coil but couldn't get it to pick up the signal. I am trying to check the output frequency of an old Heathkit HG-10 VFO. Its output is at 5 volts RMS open circuit.Thank you,Bill

author: BillyO
author_rank: Super Contributor
timestamp: November 05, 2022, 02:30:58 pm
content: You could possibly make up something with a high GBP op amp.

author: ledtester
author_rank: Super Contributor
timestamp: November 05, 2022, 02:49:16 pm
content: I have this kit and built it but I can't remember if it came with a schematic or not.In any case, in this thread:https://antiqueradios.com/forums/viewtopic.php?f=8&t=391757I found a reconstructed schematic which shows the input section:

author: ko4nrbs
author_rank: Regular Contributor
timestamp: November 05, 2022, 03:19:49 pm
content: Do you use an input buffer with it?Bill

author: Grandchuck
author_rank: Super Contributor
timestamp: November 05, 2022, 03:32:54 pm
content: You could try one of these:https://www.aliexpress.us/item/3256802963755345.html?spm=a2g0o.detail.1000060.1.9ab4792duzHSa7&gps-id=pcDetailBottomMoreThisSeller&scm=1007.13339.291025.0&scm_id=1007.13339.291025.0&scm-url=1007.13339.291025.0&pvid=9e709335-b039-46f3-b2ef-704b3131bb58&_t=gps-id%3ApcDetailBottomMoreThisSeller%2Cscm-url%3A1007.13339.291025.0%2Cpvid%3A9e709335-b039-46f3-b2ef-704b3131bb58%2Ctpp_buckets%3A668%232846%238113%231998&pdp_ext_f=%7B%22sku_id%22%3A%2212000024369199718%22%2C%22sceneId%22%3A%223339%22%7D&pdp_npi=2%40dis%21USD%213.76%212.9%21%21%21%21%21%402101d1af16676622808262566e0ffc%2112000024369199718%21rec&gatewayAdapt=glo2usa&_randl_shipto=US

author: ledtester
author_rank: Super Contributor
timestamp: November 05, 2022, 06:05:49 pm
content: Quote from: ko4nrbs on November 05, 2022, 03:19:49 pmNo I haven't used it with an input buffer. I haven't gotten around to using it with RF signals.

author: ko4nrbs
author_rank: Regular Contributor
timestamp: November 06, 2022, 04:53:05 pm
content: Hooked it up directly to my old Tektronix Constant Amplitude Signal Generator (Type 191) and the counter worked perfectly.Bill
HP3435A DMM switch cleaning - Page 1
Forum section: electronics / testgear

author: jupiters_spot
author_rank: Newbie
timestamp: November 09, 2022, 09:03:30 pm
content: I have a new-to-me HP3435A digital multimeter that's acting strangely -- the LEDs illuminating the unit enunciators are not consistent with function selection (e.g. Ohms units are illuminated when DC Voltage function is selected). I suspect I need to clean the pushbutton function selectors, but I don't see how to open them up or squirt in some DeOxit. Can anyone direct me to resource on how to clean the contacts inside these switches? They're the spring-loaded switches aligned vertically starting on the #7 of the project pad underneath the unit.(image linked from xrunner's Excellent posthttps://www.eevblog.com/forum/testgear/hp-3435a-extreme-makeover/)

author: jupiters_spot
author_rank: Newbie
timestamp: November 10, 2022, 08:27:14 pm
content: I found an articleherethat describes how to disassemble the switches - search for section entitledRepairing the Push-buttons

author: J-R
author_rank: Super Contributor
timestamp: November 11, 2022, 12:21:41 am
content: I was faced with a similar issue on my HP3466A but spraying contact cleaner in through the front of the switches while holding the board vertical was enough to solve it. Maybe someday I will need to take them apart, but for now it's OK. It is absolutely true that the bad contacts will cause the unit to switch to resistance mode.Fun story on mine, I ordered a vintage & broken Keithley DMM and the company sent me the HP3466A first by mistake. Then they sent out the correct item and told me to just keep the HP because it was faulty. But the only major issues I found were the intermittent buttons and of course bad batteries. It wasn't a vintage DMM on my radar at the time, but I enjoy having it now.The LED displays are always cool...
E44xxB ESG power level accuracy adjustment - Page 1
Forum section: electronics / testgear

author: mankan
author_rank: Regular Contributor
timestamp: January 13, 2020, 10:30:55 pm
content: I followed the advice to extend the frequency range of my E4436B in thethis thread.First I extended the range of my E4436B to 4GHz and then changed the lower limit from 100kHz (ought to have been 250kHz right?) down to 50kHz. Lower than 50kHz as TheSteve says, it drops both in output power and harmonics are staring to show. At 50kHz they are 42dBc.I also did some measurements on the output power above 3GHz and it could certainly use some adjustments. See attached spreadsheet for details.The question is how?So far I've understood that I need a Windows XP computer or VM, with a HP/Agilent GPIB adapter (USB if using VM). Will a NI PCI GPIB work if I do not use a VM?If I get that going can I just do the "High-Power" part with my HP438A and get my EEPROM settings updated?Or has anyone managed to do some more deciphering of the EEPROM data and thus found another way of adjusting the power level?

author: mankan
author_rank: Regular Contributor
timestamp: November 05, 2022, 07:59:08 pm
content: Turns out thatthis threadprovided some useful info.
Tabor 8553 Function Generator Manual - Page 1
Forum section: electronics / testgear

author: inse
author_rank: Super Contributor
timestamp: November 06, 2022, 08:10:40 am
content: Recently I bought a Tabor 8553 function generator "for parts only" from ebay.It looks like it has been tossed into the dumpster, mainly mechanical damage on the housing.Plastic screws have been used to mount transistors and regulators to heatsinks (wtf), two of them have broken off and two NiCads have leaked but fortunately not corroded the PCB.Overall the device seems to work but has not been completed yet.I am sure I will be able to figure out the standard functions, but it also has arbitrary capability which might be more challenging to use.The device seems to be from around 2000 but had been on the market for some years before.Unfortunately neither 'the internet' nor the manufacturer provide manuals, which surprises me as this had been manufactured well in the PDF era.I will give it a try and contact Tabor Electronics in Israel directly, but possibly someone here might have a user manual, maybe?...
Banggood Frequency Counter Instructions - Page 1
Forum section: electronics / testgear

author: ko4nrbs
author_rank: Regular Contributor
timestamp: November 04, 2022, 04:15:32 pm
content: Anyone got operating instructions for this?https://usa.banggood.com/1Hz-50MHz-High-Sensitivity-Frequency-Meter-Counter-Measurement-Tester-Module-7V-9V-50mA-p-1662557.html?cur_warehouse=CNThank you,Bill

author: coromonadalix
author_rank: Super Contributor
timestamp: November 04, 2022, 04:34:20 pm
content: http://myosuploads3.banggood.com/products/20200413/20200413044951featuresofE1822.pdfhttps://usermanual.wiki/m/060b1bc0ba8e7cc878b970880847beaa33e98f4e23514f69dc53be4fff53e78e.pdf

author: ko4nrbs
author_rank: Regular Contributor
timestamp: November 04, 2022, 08:56:58 pm
content: What kind of an input buffer would I need for it? I would like to measure the frequency of my old AM transmitter's external VFO.Thank you,Bill
Siglent sdl1020x-e vs Rigol Dl3021 danger? - Page 1
Forum section: electronics / testgear

author: ptluis
author_rank: Frequent Contributor
timestamp: November 03, 2022, 01:35:08 pm
content: Hello my friends,I'm in the process of buying an electronic load and I've been reading a lot of comments and posts on this forum. I have two candidates: Siglent SDL1020X-E and Rigol DL3021. The siglent seems easily hackable and has more mosfets 12 vs 10 on the Rigol (same reference IRFP250N). Rigol seems to accept 40A vs 30A on the siglent, maybe this limit can be increased in siglent as it has more mosfets?But I have a question: do any of these units check if there is a short circuit due to the mosfets failing in the shorted state?I found this situation in the following link, and it's kind of disturbing. I don't want to imagine the consequences if I connect a battery capable of 92.4v 600A to that input shorted, due to mosfet failure.I didn't find any reference to this situation in both user manualsWhat do you think?thank youoriginal link:https://mekatronik.org/forum/threads/rigol-dl3021-elektronik-yuek-tamiri.1825/Translated link into english:https://mekatronik-org.translate.goog/forum/threads/rigol-dl3021-elektronik-yuek-tamiri.1825/?_x_tr_sl=auto&_x_tr_tl=en&_x_tr_hl=pt-PT&_x_tr_pto=wapp

author: thm_w
author_rank: Super Contributor
timestamp: November 03, 2022, 09:53:21 pm
content: https://www.eevblog.com/forum/testgear/guys-cant-decide-siglent-sdl1200-xe-or-rigol-dl3021a/https://www.eevblog.com/forum/testgear/siglent-sdl1000xsdl1000x-e-electronic-load/There are some posts in the Siglent thread that the unit can be run at 300W+?DL3021 can be hacked to DL3021A with better specs, but it will still be a 200W unit.Both are decent units, price is the same, what you get depends on your preference.If you are worried about connecting large battery banks, then always use a fuse or circuit breaker on your battery pack.

author: ptluis
author_rank: Frequent Contributor
timestamp: November 03, 2022, 10:49:06 pm
content: Quote from: thm_w on November 03, 2022, 09:53:21 pmthm_w, thanks for your reply and links.

author: electr_peter
author_rank: Unknown
timestamp: November 03, 2022, 10:59:04 pm
content: Quote from: thm_w on November 03, 2022, 09:53:21 pmAll models of DL3000 series have identical HW. DL3021 can be upgraded toDL3031A(150V/60A/350W)dl3021-to-dl3031-conversion-discussion

author: ptluis
author_rank: Frequent Contributor
timestamp: November 03, 2022, 11:10:05 pm
content: Quote from: electr_peter on November 03, 2022, 10:59:04 pmThanks, that's the link for the rigol I was looking for.

author: thm_w
author_rank: Super Contributor
timestamp: November 03, 2022, 11:43:36 pm
content: Quote from: electr_peter on November 03, 2022, 10:59:04 pmThanks, thought that was missing FETs but I guess it was another model.DL3021 would be the better value option then.
Anritsu/Wiltron 68369A signal generator - FW update possible? - Page 1
Forum section: electronics / testgear

author: nexus
author_rank: Regular Contributor
timestamp: October 06, 2022, 10:55:07 pm
content: Hi all,I am looking into seeing if there is any way to update the FW on these older Wiltron designed/Anritsu branded signal generators. The specific unit I would like to update is an 68369A, but there are many models in this series that also run the same computer.I found a service manual that makes mention of different FW revisions, but there is nothing on how to perform updates. I do not see any FW files floating around online as well.If anyone has some insight into these units I would appreciate it.Thank you,Kevin

author: nexus
author_rank: Regular Contributor
timestamp: October 08, 2022, 02:10:22 am
content: lil bumpAlso posted the same question an anritsu-wiltron groups io:https://groups.io/g/anritsu-wiltron/topic/94171676#472One person indicated that FW is stored on an internal rom. Looks like the unit needs to be opened and this rom accessed to do FW stuff.Does anyone have one of these and possibly poked around in the past? Even just general pics of CPU board would be useful.

author: metrologist
author_rank: Super Contributor
timestamp: November 03, 2022, 08:28:59 pm
content: It was an easy process. The FW chip is socketed and it used an ultraviolet programmer. It will be difficult to get the FW files and figure it out though.

author: metrologist
author_rank: Super Contributor
timestamp: November 03, 2022, 08:51:58 pm
content: Also just noticed. Is that photo of your unit? That is a 68369A/NV and there would not be a FW update as it's specific to the Navy.
LeCroy WaveRunner Xi-A-N - Page 1
Forum section: electronics / testgear

author: darkstar49
author_rank: Frequent Contributor
timestamp: November 02, 2022, 06:25:09 pm
content: Just started playing with a dead WRXi-A-N that was lying around... and noticed the J6 (ATX-like) connector had been replaced by soldered metallic connectors...Not my first Xi-A (got 2 others disassembled on my bench, they have an 'ordinary' connector, like the 2 other power connectors), as the 'N' was, afaik, some 'Navy' custom version, is this related to MIL standards ?The scope is not as 'dead' as I originally thought... it's "just" the acq board, and the soft reports no h/w found and the infamous "not authorised to run on this system", but that's expected...
Signatone Quadpro Value   4 Point Resistivity Tester - Page 1
Forum section: electronics / testgear

author: Hardplates
author_rank: Newbie
timestamp: November 01, 2022, 04:25:01 pm
content: I purchased this unit from an auction at a college while bidding on some other items with the intention of keeping one of the meters and selling the other.After a little research it appears the unit may have more value intact than in pieces.Would anyone happen to have an idea of what fair market value would be for such an instrument?Thanks in advance.
Tracking Generator Solution for HP S/A - Page 1
Forum section: electronics / testgear

author: jlmoon
author_rank: Unknown
timestamp: June 18, 2014, 04:07:20 pm
content: Hello all,I am in need of a Tracking Generator solution for a Hp 8563A spectrum analyzer, does anyone know of a good match / fit for this series of equipment? I know hp made a 85640A but that device covers up to 2.9Ghz, this seems to be a bit of a mismatch for a analyzer that is good for >20Ghz. Any suggestions? Trade for a new one.. , kick it to the curb...Thanks in advance,JLM

author: cyr
author_rank: Frequent Contributor
timestamp: June 18, 2014, 05:13:24 pm
content: What are your requirements?I've cobbled together something useable for the first two bands of my 8562E (0-2.9GHz and 2.7-6.5GHz) from a few ebay parts and a RF synthesizer chip.Essentially this, but different components and two settings for the oscillator frequency:http://www.qsl.net/n9zia/tracking/index.htmlIt has no ALC, level adjustment or filters for unwanted spurs - but it works reasonably well for filters and antennas etc.

author: G0HZU
author_rank: Super Contributor
timestamp: June 18, 2014, 06:12:52 pm
content: I think the official solution is the 26.5GHz HP85645A tracking source and these were made in the 1990s. The HP85644A is similar but only covers to about 7GHz.But these are rare and usually command big prices despite their age. The HP85645A cost about $30k when new. The 7GHz version cost about $23k new. They often sell for about $8k used which reflects the supply and demand situation due to the rarity.I've got one here for my HP8566B analyser but I don't really want to sell it. You can use it as a signal generator as well as a tracking source and that's what I use it for the most. It's very accurate in terms of level from -80dBm to about +13dBm in both tracking and sig gen mode.

author: G0HZU
author_rank: Super Contributor
timestamp: June 18, 2014, 06:21:46 pm
content: I think the best thing to do would be to keep the HP8563 and just keep a lookout for a decent VNA. eg a 6GHz HP8753C/D will usually cost less than the HP85644A 7GHz tracking source and a LOT less than the HP85645A tracking source. Also it will totally outclass the analyser + tracking source in terms of accuracy and versatility, especially if you get a full two port version of the 8753 VNA.But it all depends on what you want to do and how much you want to spend.

author: pe2ben
author_rank: Contributor
timestamp: October 31, 2022, 05:00:25 pm
content: How do you think about this tracking generator?https://www.dsinstruments.com/product/rf-tracking-generators/12ghz-tracking-signal-generator/Regards Ben
Bench DMM  Victor 8245 vs VICHY VC8145 - Page 1
Forum section: electronics / testgear

author: ColCon
author_rank: Contributor
timestamp: May 20, 2019, 04:47:50 am
content: I would like to ask which of these you would prefer or recommend for a budget bench DMM. Thanks very much. I'd appreciate any insight.Victor 8245https://www.amazon.com/Measurement-Bench-Type-Multimeter-220mV-1000V-22nF-220mF/dp/B078SLSHP5VICHY VC8145https://www.amazon.com/d/Multi-Testers/VC8145-Digital-Multimeter-000counts-Voltmeter/B00S7KIKRK

author: nctnico
author_rank: Super Contributor
timestamp: May 20, 2019, 08:54:59 am
content: These seem pretty much equal from a functional point of view. I'd buy the cheapest one. I have a couple of VC8145s myself and they still work great after several years.

author: ColCon
author_rank: Contributor
timestamp: May 21, 2019, 12:36:51 pm
content: Thanks. I see quite a bit of info on the VC8145 on the web, but almost nothing on the Victor 8245. Not even photos, other than the one full-frontal on Amazon.

author: beltet
author_rank: Newbie
timestamp: May 22, 2019, 07:41:53 pm
content: I was looking for a budget bench MM recently and landed on the VC8145 because of the good value on it. I had a budget for around 150$ and all others had similar specs with higher price and it was not that far from a real brand meter. So what I really did was choose between the VC8145 and a known brand meter. And for my purposes I don't need a known brand.

author: graybeard
author_rank: Frequent Contributor
timestamp: May 25, 2019, 12:29:37 am
content: The Victor web site only shows 220V power compatibility for the Victor 8245.

author: LinuxHata
author_rank: Frequent Contributor
timestamp: November 02, 2022, 05:09:48 am
content: I'm also considering buying VC8245, due to it's "nostalgic" VFD display, but found absolutely no mentioning from real users online, dunno why...

author: simba15
author_rank: Regular Contributor
timestamp: November 02, 2022, 02:30:25 pm
content: VC8215 is good.But the Victor is a clear duplicate of the HP 34410a design.Here is a video of 8426ASeems quite good but the price is much more than the 8125.
Recapping Tektronix 7904, 7844 etc. power supply - Page 1
Forum section: electronics / testgear

author: Gianni
author_rank: Contributor
timestamp: October 29, 2022, 04:01:43 pm
content: Dear friends,I ask your help for the power supply of my 7844 (that is almost identical to 7904 and others). I arrived to it for a problem in the readout, with characters that dances in a strange way, but that is not the point.The problem for which I am asking your help is the recapping of the power supply, that I am investigating because its ripple value is definitely not good. The table below shows the values (in mV) I measured with a 7A22 differential vertical amplifier.The question is: did anyone recapped a power supply like that? I dismounted the power supply and:I am not going to replace the two large 900uF capacitors because they seem to have maintained their value (I measured about 1300uF for both);I am going to replace all the other electrolytic capacitors in the rectifier board.What is your opinion about all that above?Thanks
GW Instek LCR 918 to LCR 921  Upgrade - Page 1
Forum section: electronics / testgear

author: gogoman
author_rank: Regular Contributor
timestamp: October 29, 2022, 08:01:09 pm
content: Hello, this is a long shot, but I'll put it out there anyway.I have a new to me LCR-918, the top dog is the LCR-921. Is it possible to update the FW from a lower model to the 921.if so how?thanks
LeCroy WaveRunner 6000(A) LCD   - Page 1
Forum section: electronics / testgear

author: darkstar49
author_rank: Frequent Contributor
timestamp: October 29, 2022, 03:36:33 pm
content: nothing groundbreaking, but as I was just busy replacing the motherboard of 2 6100A's (with some from Kontron), I though I'd publish the SDVO/LCD pinout, for those who'd need to make their custom LVDS cable, too...I used a 20-wires pre-crimped cable, but some other LCD's/mainboards may require a different number of wires.the LCD connector on the front panel board of the (A) series is compatible with a Hirose DF19-20 connector, the backlight (inverter) connector (on the cable) is JST S5B-PH 5-pin female connector (I didn't use it, and soldered the power supply lines from the motherboard onto the wires directly)
TLA7SA08 Failing Self test - UFDC module - Page 1
Forum section: electronics / testgear

author: nicklinn
author_rank: Contributor
timestamp: October 04, 2022, 05:32:54 pm
content: Hello,Am attempting to save a TLA7SA08 module for the TLA7000 series logic analyzer for a project. It's only failure is on the UFDC module, I can't for the life of me find any documentation on what the heck this module is to even start. Anyone have an idea?Thanks,Nick

author: nctnico
author_rank: Super Contributor
timestamp: October 04, 2022, 06:48:24 pm
content: Quote from: nicklinn on October 04, 2022, 05:32:54 pmOpen it up and look on the silkscreen to try and find a clue. While you are at it, look for any physical damage.

author: nicklinn
author_rank: Contributor
timestamp: October 05, 2022, 03:34:25 am
content: Quote from: nctnico on October 04, 2022, 06:48:24 pmThing is pristine on the inside and nothing labeled that unfortunately.

author: calibrationfixture
author_rank: Regular Contributor
timestamp: October 29, 2022, 06:08:38 am
content: Hi Nick,I assume you powered this Module up isolated. Thus all other Modules not connected in the TLA7000 Mainframe. In addition you also tried another Slot. This is a suggestion in the 077-0402-02 TLA7SA08 & TLA7SA16 Technical Reference Manual (last 2 pdf pages).I also assume you installed the TMS160PCIE3_v6.0.267.0 Application Firmware. The Software for the Serial Analyzers isn't included in the "normal" TLA Application Software (this must be V5.8 at least).UFDC Modules Tests are in the beginning of the Power-On and Extended Diagnostics Tests. TLA7AXX, TLA7BXX and TLA7SAXX's show this description. TLA7NX Modules show SFDC Modules Test. These need a Jumper for FW Reflash. TLA7AXX e.a. not. Maybe this is the area you must look to.Succes,
Tektronix 7844 traces fade with scan speed - Page 1
Forum section: electronics / testgear

author: Gianni
author_rank: Contributor
timestamp: October 28, 2022, 03:27:50 pm
content: Hi,I have a 7844 oscilloscope that has two problems:1) traces fade with scan speed, until they are no longer visible at 50ns/div; if I raise the intensity, I only lose the focus. The problem is exactly the same on both beams.2) the readout "dances". I have already tried changing the whole board with another that is certainly good, but nothing changed. All voltages seems to be right and clean.I have a video but I am not able to upload it (which format should I use?)Unfortunately I have not a high voltage probe, but in 7844 I do not find a test point for it however.Can anyone please give me some direction where to investigate?Thanks

author: perdrix
author_rank: Frequent Contributor
timestamp: October 28, 2022, 08:49:24 pm
content: Which timebase are you using? What frequency is the signal - if you're using a 1kHz signal you should not expect to be able to see it at 50nS/div- think about it for a while and you should be able to work out why.D.
Question on HP-3580A parts list for HV section - Page 1
Forum section: electronics / testgear

author: slbender
author_rank: Regular Contributor
timestamp: October 28, 2022, 07:01:25 pm
content: Greetings,If I recall correctly the high voltage board in this 3580A vintage set’s “Parts List” listed only a single really high voltage diode as: 10mA/7.5KV, with several nearby diodes in the same circuit as rated at only 200 volts. Could this be a misprint? I suspect the high voltage is out in my set so I ordered some 30mA/8KV replacements, along with some HV caps. Rather be safe than sorry anyone know this answer???Steven

author: slbender
author_rank: Regular Contributor
timestamp: October 28, 2022, 08:20:33 pm
content: Ok, the early (1980) HP-3580A manual list’s a single A11A1CR5 as that high voltage 7.5kV/10mA diode and A11A1CR1-4 as: 180V/200mA, for early serial number sets.The 1987 revised 3580A manual lists A11A1CR1 and A11A1CR2 diode’s as 7kV/50mA. Confused yet?The associated caps also get changed, three 1kV caps (C1=.001, C2,C3 =.01uF) and three (4700pF=.0047uF) 4kV caps in the early sets, but six 4700pF/4kV caps in later serial number sets. So now I sayI suspect my set is later than either manual because it has the red leds readout instead of the mechanical geared unit. Anybody have data from a manual later than 1987 with better information?Steven
Pass/fail mask test on Rigol DS1000Z series  - Page 1
Forum section: electronics / testgear

author: Miti
author_rank: Super Contributor
timestamp: October 28, 2022, 04:35:30 pm
content: I need to use a scope to check some waveforms in an automated test equipment. I was thinking of using a cheap DS1000 and do a pass/ fail test but I can’t find commands to load a mask that was created manually and saved on the external USB drive. Can DS1000 read from the external drive through a command or it is only manual?Cheers,Miti

author: Fungus
author_rank: Super Contributor
timestamp: October 28, 2022, 04:51:07 pm
content: Quote from: Miti on October 28, 2022, 04:35:30 pmI can't see any SCPI commands to load/save the masks.It looks like they have to be loaded/saved manually.Programming manual:MSO1000Z/DS1000Z_Programming Guide_EN.pdf

author: Miti
author_rank: Super Contributor
timestamp: October 28, 2022, 06:42:18 pm
content: Quote from: PeDre on October 28, 2022, 05:28:47 pmThanks Peter, it works like a charm!Cheers,Miti
XDM1041 meter: a damning flaw? - Page 1
Forum section: electronics / testgear

author: cvanc
author_rank: Frequent Contributor
timestamp: October 28, 2022, 10:26:47 am
content: Guys, I own two of these and have found they are utterly incapable of reading the AC ripple of a DC supply.You read that right. It can't read small AC in the presence of DC. At all. It just reads zero.I'll post pics showing what I'm on about, but if any other owners wanted to check theirs it would be very helpful. Thanks.

author: blackdog
author_rank: Frequent Contributor
timestamp: October 28, 2022, 10:52:34 am
content: Hi cvanc,It is al in the specs of this meter, 500mV is the lowest range in AC and also with a limited frequency range.So it is not the wright instrument to do this kind of measurements.Kind regards,Bram

author: hgjdwx
author_rank: Regular Contributor
timestamp: October 28, 2022, 01:56:47 pm
content: xdm1041 AC bandwidth only 1khz
Keithley 2000 forgets settings on restart - Page 1
Forum section: electronics / testgear

author: Spirit532
author_rank: Frequent Contributor
timestamp: October 27, 2022, 09:03:42 pm
content: I'm having an odd issue with my K2000, Rev 05 A02. Whenever I power it on, it automatically defaults to DCV measurement, in "Timer" mode, on "Med" sample rate. I've tried saving new settings(shift->save->yes) and then choosing user settings for power-on(shift->setup->user), but nothing seems to work.Any idea what might be causing this?There are no errors, it's in(outdated) cal, and it works perfectly fine otherwise.

author: jjoonathan
author_rank: Frequent Contributor
timestamp: October 28, 2022, 02:53:23 am
content: I dunno, probably a dead sram battery or eeprom or something -- hopefully real K2000 owners can chime in -- but if you decide you want to chase after this fly with a hammer, I have some copypasta for you.https://www.eevblog.com/forum/testgear/instek-gpp4323-beep-volume-can-it-be-decreased/msg4465915/#msg4465915

author: J-R
author_rank: Super Contributor
timestamp: October 28, 2022, 04:39:50 am
content: Once powered on, can you restore the user setting successfully? In other words, is it not remembering the settings stored in USER or is it not restoring USER at power on?

author: Spirit532
author_rank: Frequent Contributor
timestamp: October 28, 2022, 04:41:51 am
content: Quote from: J-R on October 28, 2022, 04:39:50 amYup, I can save and restore USER, including through power cycles. It's not restoring it automatically, on power on.

author: chekhov
author_rank: Regular Contributor
timestamp: October 28, 2022, 01:49:28 pm
content: Maybe that's an indicator of "You have to change FLASH chip ASAP until you lost your calibration" ?The one thing that is not clear for me, has it worked before ?I have meter with revision 06, I tried to (save, power off-on, setup factory, save, power off-on), and custom settings appear on boot.If you are going to replace FLASH chip, dump CAL coefficients first before touching it, just to be on the safe side.
Mastech MS8360E dial contacts positions - Page 1
Forum section: electronics / testgear

author: Rack201
author_rank: Contributor
timestamp: October 24, 2022, 04:58:17 am
content: Hi - probably stretching my luck, but I was cleaning some moisture out of my Mastech MS8360E meter and disturbed the contacts on the back of the dial before I got a pic. Wondering if anyone has a pic that can show my which positions they sit in?Regards

author: Tjuurko
author_rank: Regular Contributor
timestamp: October 28, 2022, 03:58:51 am
content: https://jais.ru/media/uploads/ms8360e-5.jpg
Rohde&Schwarz RTB2004 spectrum remote control - Page 1
Forum section: electronics / testgear

author: twtb
author_rank: Contributor
timestamp: October 27, 2022, 06:11:44 pm
content: We are trying to use a RTB2004 for some automated spectrum measurements. The intention is to use an external application to control the scope for FFT and get spectrum traces.The following commands are used to set the center frequency and span. We see these settings correctly applied on the screen of the scope.SPECtrum:FREQuency:CENTer 25000000SPECtrum:FREQuency:SPAN 10000000Then we use this command to retrieve the traceSPECtrum:WAVeform:SPECtrum:DATA?This returns a big list of points, however it looks like the range is not from 20 to 30MHz (with our 25 MHz signal in the middle), but rather from 0 to 30 MHz. Our 25MHz signal is on the right when we create a plot. This is also confirmed by the "SPECtrum:WAVeform:SPECtrum:DATA:XORigin?" command, which returns 0Hz as first frequency. Unfortunately that command is read-only.What could be the cause of this? How can we only get the trace points of the configured range?Documentation:https://www.rohde-schwarz.com/webhelp/RTB_HTML_UserManual_en/Content/c0f97ffea4c3453c.htm
Accidentally fried wave generator output of Hantek DSO2D10. Is that fixable?  - Page 1
Forum section: electronics / testgear

author: LinuxHata
author_rank: Frequent Contributor
timestamp: October 28, 2022, 04:22:42 am
content: Connected the generator output probe to 12VDC power supply (generator output was not active). There was a bad smell from the scope and power supply entered into short circuit protection. Now scope works partially - both channels are working as usual, but wave generator output and external trigger does not work at all. I rarely use any of them, and scope is long time out of warranty, so the question is, that I believe, this might be a common issue, so maybe anyone have experience in fixing this? is there a circuitry of this scope available?

author: pcprogrammer
author_rank: Super Contributor
timestamp: October 28, 2022, 06:13:37 am
content: Schematics and other information can be found here:https://github.com/pecostm32/Hantek_DSO2000With a bit of luck it only fried the protection diodes into a short.

author: Kleinstein
author_rank: Super Contributor
timestamp: October 28, 2022, 06:27:29 am
content: As the external trigger is also not working the protection diodes (or at least one of them) are very likely dead. There is a chance this could be the only damage. Though outside the specs the OP-amp could have survived some 12 V via 50 ohms.Even than it would still be viabel to also exchange the amplifier.The protection looks a bid odd. Instead of the diodes to the +-5 supply it would be more sensible to have transsorbs towards ground and ideally with polymer fuse as part of the 50 Ohms matching resistance.

author: pcprogrammer
author_rank: Super Contributor
timestamp: October 28, 2022, 06:58:57 am
content: If the generator is not enabled the relay is set to external trigger and the opamp would not have received the blast.

author: LinuxHata
author_rank: Frequent Contributor
timestamp: October 28, 2022, 08:11:21 pm
content: Thanks a lot!Will have look next week...
GW Instek ASR-2000 Power Off Alarm - Page 1
Forum section: electronics / testgear

author: Xandinator
author_rank: Contributor
timestamp: October 24, 2022, 11:27:36 am
content: Hi,Anybody out there also annoyed with the ASR-2100 Power Off Alarm and found a workaround? I would not want to "turn off" the alarm permanently by simply disconnecting the buzzer for obvious safety concerns but since I do my stuff during Madam's sleeping hours I left the thing running instead of hauling it to another room (still being plugged in)...Any helpful advice greatly appreciated!

author: Adrian_Arg.
author_rank: Frequent Contributor
timestamp: October 24, 2022, 09:31:56 pm
content: disconnect the lady

author: Xandinator
author_rank: Contributor
timestamp: October 27, 2022, 09:15:10 am
content: no can do, warm-up time after reconnecting far too long, plus risk of losing one order of magnitude in long-term stability, also repeatability severely suffering
SCPI "TRACe:DATA?" command on SVA1015x - Page 1
Forum section: electronics / testgear

author: Meestor_X
author_rank: Contributor
timestamp: October 26, 2022, 11:04:48 pm
content: Is there a beginners guide to using this command?With the SVA in SA mode, It seems to spit out 35 1/2 values, how do I know what frequency each one refers to? How do I get more than 35 values?Thank you for any and all help!

author: Tony_G
author_rank: Super Contributor
timestamp: October 27, 2022, 03:02:09 am
content: This is probably a limitation of the UI rather than the unit directly - I've never used this SA but it certainly looks like the UI is just truncating the buffer - Install whatever the appropriate communication software is (NI VISA, Keysight IO Libraries, PyVISA etc) and then write a small program to send the command and read back the data - You'll probably end up with several hundred values that will be distributed from the start and stop frequencies of the sweep - For example, my HP 8563E returns 601 values so I would simply calculate the frequency based on start, stop, divided by 601.Not sure if this helps very much but maybe it'll help you find the right answer.TonyG

author: Meestor_X
author_rank: Contributor
timestamp: October 27, 2022, 03:03:18 am
content: Thank you. I'll give that a try!
Keysight 34465A vs Fluke 8846A vs others - Page 1
Forum section: electronics / testgear

author: arijav
author_rank: Contributor
timestamp: October 26, 2022, 09:06:41 pm
content: Hello,I am currently planning to buy a 6.5 digit DMM for a lab. We plan to use it to calibrate measurement systems (German DAkkS) where we need to go to accuracies in the order of 0.1mV for a voltage range of +/-10V. We need as well to calibrate thermocouple inputs. We have been using to calibrate our equipment in the past a Fluke 8846A which was sent yearly for an official DAkkS calibration. I need to buy a new unit and I am wondering about what would be the best option nowadays. Would you recommend the Keysight 34465A?, still a Fluke 8846A or something else?.I understand both the Keysight as well as the Fluke use LM399 voltage references. For this price range there is none with LTZ1000 right?Thanks

author: bdunham7
author_rank: Super Contributor
timestamp: October 26, 2022, 09:17:35 pm
content: Quote from: arijav on October 26, 2022, 09:06:41 pmThe Fluke 8846A is discontinued, but Welectron may still have some stock. What happened to yours?I think someone made a home-brew LTZ1000 setup for the Keysight 34465A, but in general just changing the reference doesn't help much. An aged and selected LM399 is more than good enough for this type of meter and other issues (tempco of divider resistors, etc) will dominate the errors.The Keithley DMM6500 is the designated replacement for the 8846A.Your stated accuracy requirement of +/- 0.1mV @ 10V is 10ppm, a spec which is not specified by any 6.5-digit meter and is also beyond the specified capability of even 7.5 digit meters like the Keithley DMM7510 or Keysight 34470A. Only 8.5 digit meters achieve <10ppm. Your 8846A may have been performing this well in actual practice (mine does, easily) but it isn't specified to, so I don't know how that affects your requirements.

author: arijav
author_rank: Contributor
timestamp: October 26, 2022, 09:48:10 pm
content: Thanks for your input, specially related to the need of a 8.5 digit one to reach the ppm. Up to now somehow it was working fine with the Fluke, so we will try to stay in 6.5 to keep the costs reasonable. Regarding the Fluke 8846A, it is still fine, the reason to acquire a new DMM is because we have now a second lab location and we wanted to have one there as well.

author: bdunham7
author_rank: Super Contributor
timestamp: October 26, 2022, 09:55:28 pm
content: Quote from: arijav on October 26, 2022, 09:48:10 pmIn that case I'd recommend you contact Welectron immediately to see if they still have the 8846A in stock and just buy it if they have it. None of its competitors nor any available replacement quite match its accuracy and stability, in theory (specification) or in practice.
National Instrument USB DAQ Alternatives - Page 1
Forum section: electronics / testgear

author: rvalente
author_rank: Frequent Contributor
timestamp: October 24, 2022, 05:53:59 pm
content: Hello Mates,National USB 6000 Series DAQ could be very useful for a bunch of industrial applications but they're quit expensive when a panel PC is included on the system. Is there other vendors alternatives?

author: alm
author_rank: Super Contributor
timestamp: October 24, 2022, 08:47:31 pm
content: What are you looking for? You mention the PC is a large part of the cost. I don't think $200ish is very expensive for an industrial device. Would something with a wired or wireless Ethernet interface save on the number of computers you need?Look atLabJack. Their prices will probably not be much, if any, lower, but they have some features like Ethernet connectivity and Lua scripting (in the T-series) that might cut down on the number of computers you need. Obviously you could make something with an Arduino, but I wouldn't mess with that in an industrial environment.

author: rvalente
author_rank: Frequent Contributor
timestamp: October 26, 2022, 11:38:04 am
content: Actually NI Hardware is quite expensive, a USB-6009 is at $524 at newark, the importing costs in Brazil is often ridiculous so this could almost double.I'll check labjack, tks!
Tenma 72 7290 ac adapter or battery ? - Page 1
Forum section: electronics / testgear

author: Dajaab
author_rank: Newbie
timestamp: October 25, 2022, 11:33:33 pm
content: Hi everyone,I just received a nice combo Tenma 72 7290, everything seems ok except the multimeter.The multimeter works with an external power supply or a battery ?It seems to be 9vDoes anyone has the same Tenma ?Or the schematic or manual ?Thanks in advance for your help

author: ledtester
author_rank: Super Contributor
timestamp: October 26, 2022, 10:30:01 am
content: It is possible this thread is relevant:https://www.eevblog.com/forum/reviews/metex-universal-combined-test-instrument-systemsstations-a-look-inside/In particular starting at this post:https://www.eevblog.com/forum/reviews/metex-universal-combined-test-instrument-systemsstations-a-look-inside/msg121973/#msg121973Also possibly this post:https://www.eevblog.com/forum/reviews/metex-universal-combined-test-instrument-systemsstations-a-look-inside/msg928481/#msg928481
Keithley 220 Firmware Ver B11 - Page 1
Forum section: electronics / testgear

author: Zucca
author_rank: Unknown
timestamp: June 18, 2014, 03:35:51 am
content: Hello Guys,I just read out the two Prom 2732 of my Keithley 220. I think it would be useful to share the .bin.The FW Version displayed at power up is B11.Here the chip:Attached the two .bin files.Ciao,Z

author: jrmymllr
author_rank: Regular Contributor
timestamp: October 26, 2022, 06:27:41 pm
content: Bet you never thought someone would reply to this 8 year old message (and maybe I shouldn't) but I only wanted to say I recently did this too, and your images match mine exactly

author: coromonadalix
author_rank: Super Contributor
timestamp: October 26, 2022, 06:49:13 pm
content: You never know ...