hybridfree/eevblog-posts huggingface dataset:
High Voltage Bipolar Replacement type(s) for MJ16012 in HP 8663A ? - Page 1
Forum section: electronics / testgear

author: Uky
author_rank: Regular Contributor
timestamp: December 04, 2023, 07:48:57 am
content: Greetings.I picked up an HP 8663A on a flea market with a not working inverter.The design uses two high voltage bipolar transistors MJ16012.One of them was broken and one of the electrolythinc capacitors in the samecircuit was "boiled" (short circuited).I was able to repair the inverter, replacing the transistors with BUX48that I had in my junk box but now my supply of bipolar high voltage types are depleted.DigiKey and Mouser lists a few types that are still produced and most likelyavailable. The BUX48 had specifications that was "near" those of the MJ16012but I do not know if my choise will be long lived. About one hour afterhaving had the instrument in operation, I turned the instrument OFF,disconnected the AC (pulled the plug), quickly removed theinverter PCB and tried to asess if there were any signs of thermal stress on thereplaced components. They were all att room temperature. At least not any signsof heat dissipation in the electrolythic capacitors ((2x10 uF/350V) x 2)As I have read, there are more than one enthusiast that has had problems with this inverterboard. If any one would be willing to share what other type(s) of high voltage bipolarsthat worked I would be grateful.CheersUlf KylenfallSM6GXV
Decoding signals in Rigol Ultrascope software - Page 1
Forum section: electronics / testgear

author: rokspy
author_rank: Contributor
timestamp: November 27, 2023, 11:43:06 pm
content: I'm measuring RS232 coded signal with my scope and then viewing the signal through Rigol Ultrascope software on my PC. My goal is to read the decoded characters. The Scope itself has no trouble decoding the signal and showing characters, but I'm having trouble with reading the characters on the Ultrascope software as there are no clear way to enable decoding. Am I missing something or does the Ultrascope software simply lack the decoding functionality (which would be super annoying)?

author: thm_w
author_rank: Super Contributor
timestamp: November 28, 2023, 12:58:09 am
content: What oscilloscope do you have? Some are supported under Sigrok, which can run on the PC. Another option might be to use the remote web control if your model supports it.Most people don't use Ultrascope for anything.The best way to decode on PC is usually to get a USB logic analyzer, they can be had for as little as $10.

author: Fungus
author_rank: Super Contributor
timestamp: November 28, 2023, 01:22:02 am
content: Ultrascope!
TinySA Sweep sync pulse - Page 1
Forum section: electronics / testgear

author: alonsojar
author_rank: Contributor
timestamp: November 27, 2023, 12:16:29 pm
content: Hello,For those having or considering a TinySA device and didn't notice this feature, I discovered by chance that the sweep function available when the device is configured as signal generator in the Low speed port, can have a sync pulse to help triggering a scope.The pulse is emitted by the High port every time the sweep is restarting in the Low port. This may be helpful tuning radio IF transformer cans for instance.After noticing this, I did a little search and it looks this was implemented in a recent fw (I'm running 1.4-128) and in theory is activated using "config->more->high pulse" check box, but at least in my device, an original TinySA, not the Ultra version, it seems it's always active while the the sweep is on.This is how it looks

author: Aldo22
author_rank: Super Contributor
timestamp: November 27, 2023, 02:06:31 pm
content: Thanks for the hint!And as I've just updated my TinySA: Since the update from 2023-11-25, modulation frequencies < 50Hz now also work.

author: wasedadoc
author_rank: Super Contributor
timestamp: November 27, 2023, 05:36:50 pm
content: Quote from: alonsojar on November 27, 2023, 12:16:29 pmTinySA (Not Ultra) 25 Nov 2023 firmware. Pulse from High Output:In Signal Generator Mode, RF from Low Output and Sweep on, the pulse is always output from the High connector.In Spectrum Analyser mode, the pulse is present or not according to the menu setting.
Keysight EDU33212A bandwidth upgrade (hackable perhaps?) - Page 1
Forum section: electronics / testgear

author: Anthocyanina
author_rank: Frequent Contributor
timestamp: November 30, 2023, 07:32:46 pm
content: so a new firmware was released for the EDU33212A generator, and while there's no mention of fixing the bugs, they've added support for a bandwidth upgrade called 332BW2U which doesn't appear on their website, but can be found herehttps://www.meilhaus.de/332bw.htm?b2b=0the upgrade is very minor and very expensive, adding just an extra 5MHz for a total bandwidth of 25MHz, which i think is only for sine waves(and you can get sine waves well beyond 20MHz using its arb capabilities)with the PCB having a "30M" label, i wonder if they'll eventually add another upgrade to support that bandwidth, but at that cost...anyway, i was able to do some modification of a previous firmware to change the arb waveforms, although not their names, and i am very inexperienced in firmware modification, so perhaps this option can be unlocked by someone more knowledgable!edit: it really is just 5MHz extra sine wave range

author: armandine2
author_rank: Frequent Contributor
timestamp: November 30, 2023, 09:18:25 pm
content: Other than you, me, and Dave I wonder who has one of these and is in a position to play around with it?I'm mildly embarrassed to have one, Dave was given his, and you won it in competition - so who else exactly is the market?

author: Anthocyanina
author_rank: Frequent Contributor
timestamp: December 01, 2023, 01:19:23 am
content: Quote from: armandine2 on November 30, 2023, 09:18:25 pmyeah, it's unfortunate how little value this generator has for the hobbyists at such a price point, i'm mostly happy with it(minus a few burst and arb bugs, and the slow front panel), but yeah, it not being much value for money makes it very hard to find other people using it who can confirm if something is a bug, or produce software *enhancements* for it. I had a minor incident with milkthat required me to open it to clean the connectors and i saw the cal BNC is also labeled modulation on the pcb, and when you go to modulation, you see an option for source, but only internal is available, which makes me think enabling external modulation should be possible, and that would make this generator that much nicer too.

author: armandine2
author_rank: Frequent Contributor
timestamp: December 01, 2023, 07:24:01 am
content: Quote from: Anthocyanina on December 01, 2023, 01:19:23 ama case of not crying over spilt milk?

author: Anthocyanina
author_rank: Frequent Contributor
timestamp: December 01, 2023, 08:00:23 am
content: Quote from: armandine2 on December 01, 2023, 07:24:01 ama case of barely not crying!fortunately the generator was off, i was fast to take it apart, and the milk *only* got into the usb connector, a bit under the display bezel, and a couple of BNCs
Siglent SPD3303X: Slight negative voltage when outputs are off - Page 1
Forum section: electronics / testgear

author: brendar
author_rank: Newbie
timestamp: November 26, 2023, 03:26:24 pm
content: I recently received a new Siglent SPD3303X power supply and after running through some initial tests I noticed something odd: when the unit is on but the outputs are off, I'm measuring a negative voltage of -14 mV on CH1 and CH2, but CH3 measures 0 V as I would expect. Those measurements were taken on a Fluke 117 DMM using its included probes. I contacted Siglent about this and they stated that the unit is not defective and a negative voltage is expected in this situation. My question for you all is: how concerned should I be about this? Under what scenarios could that negative voltage be problematic? I'm new to electronics and not sure what's normal when it comes to bench power supplies.

author: Gulftown
author_rank: Regular Contributor
timestamp: November 26, 2023, 04:03:36 pm
content: Hi,in my opinion, you souldn't be too concerned.On linear power supplys without relays on the output this behavior is pretty nomal.My SPD3303X does the same.When i short the outputs with a 50 Ohm Resistor, the voltage drops to -0.6 mV already.I dont think, that any commonly used circuit will be damaged from this.
Influx of new Fluke 87V's with 2014 manufacturing dates. How come?  - Page 1
Forum section: electronics / testgear

author: StueyB
author_rank: Newbie
timestamp: November 27, 2023, 10:27:35 am
content: So I'm missing my Fluke 87V and happened to see quite a few for sale on an auction site from various unrelated sellers all with 2014 manufacturing dates.The only genuine reason I can think of is some kind of legislation regarding expiration of inventory after 10 years, perhaps government / industry legislation?I'm really fancying one but I'm a bit twitchy about the whole thing.Can anyone elaborate who has an idea why this may occur?Stu

author: Fungus
author_rank: Super Contributor
timestamp: November 27, 2023, 03:24:35 pm
content: Probably a government agency had a huge stockpile of them and they auctioned them off recently.Your tax $$$ at work.

author: H.O
author_rank: Frequent Contributor
timestamp: November 27, 2023, 06:25:51 pm
content: Nah, some military guy wrote a new test procedure on how to test coin cell batteries.In it he specified the multimeter used was a Uni-T UT33+, rendering all the 87V's obsolete.

author: BeBuLamar
author_rank: Super Contributor
timestamp: November 27, 2023, 06:45:15 pm
content: How do you check the manufacturing date?

author: themadhippy
author_rank: Super Contributor
timestamp: November 27, 2023, 06:48:20 pm
content: The batterys are flat, compared to the the cost of carrying out a risk assessment on live working ,writing a method statement on how to change the battery and carrying out an environmental study on the safe disposal of the battery it works out cheaper to buy new.

author: BeBuLamar
author_rank: Super Contributor
timestamp: November 28, 2023, 12:22:31 pm
content: I would like to ask the OP again. How do you know the manufacturing date?
Tektronix 577 step generator switches bad - Page 1
Forum section: electronics / testgear

author: Swake
author_rank: Frequent Contributor
timestamp: November 24, 2023, 01:35:34 pm
content: Hi,Started the repair of a Tektronix 577 curve tracer and found that most of the switches in the step generator area are bad. Have yet to check the other switches.What is the best way forward cleaning these switches?
Another bug in the Rigol DHO914S/DHO924S Bode Plot feature - Page 1
Forum section: electronics / testgear

author: BobWalance
author_rank: Newbie
timestamp: November 23, 2023, 07:57:37 pm
content: I have a DHO924S and have been using the Bode Plot function. As some of you might already know, Rigol's implementation of bode plot in these scopes is very poor. The gain and phase responses have erroneous ripples and discontinuities. Hopefully they will correct this issue.There is another problem that we should all be aware. I have firmware version 00.01.01 (the latest as of November 2023).If the scope is configured so that the last settings are used when the unit is powered-ON (Utility->Setup->Load last=Last), and if the scope is powered-OFF when the bode plot window is open, then the scope will become unresponsive when the unit is powered back ON.When this happens, the scope will apparently still be in bode-plot mode but the bode-plot window will not be visible, so it can't be closed.The only way to recover from this is to press the DEFAULT button. This will also cause all of the probe settings (e.g. '10x') to be lost.Of course, if the scope has been set to 'Default' mode (Utility->Setup->Load last=Default) then the scope will not get into this funky mode. However, the 'Load last=Last' is convenient so that the probe settings do not have to be reloaded every time the scope is turned on.I have made Rigol aware of this problem.

author: Fungus
author_rank: Super Contributor
timestamp: November 23, 2023, 09:10:13 pm
content: Quote from: BobWalance on November 23, 2023, 07:57:37 pmDo you have a good contact there? I'm sure we could put together a list of things that need fixing.There's only a few on the DHO800:1) Settings aren't saved properly. It doesn't remember the setting for horizontal knob push (fine/zoom) and the window transparency follows the waveform intensity when you reboot (set waveform intensity to 100% and reboot twice, your window transparency will be 100%).2) Serial decoder threshold level doesn't use the probe attenuation setting, you have to set probe to 1x for it to work.3) If you press "STOP" and increase the vertical scale it goes wrong after six clicks (trace on screen doesn't match the numbers down the side).4) The window is the wrong size in the web control interface, it sets 1280x800 - the size of the DHO1000.Maybe this could be a good thread to post JUST BUGS. No discussion of them here - there's already a thread for that, discuss them over there and post them here when they're confirmed/reproducible. Keep this thread as short as possible.

author: Martin72
author_rank: Super Contributor
timestamp: November 23, 2023, 10:36:14 pm
content: Only four bugs, making it the most mature scope on the market.Apart from this, I think we don´t need for every bug a new topic:https://www.eevblog.com/forum/testgear/rigol-dho800900-oscilloscope-bug-reports-firmware/msg5089921/#msg5089921
R&S VNA ZVRE 1043.0009.50 Firmware - Page 1
Forum section: electronics / testgear

author: BoscoLab
author_rank: Contributor
timestamp: November 23, 2023, 07:49:54 pm
content: I am looking for the firmware for a ZVRE 1043.0009.50. The VNA is currently equipped with firmware 1.70. I think this is still the DOS version. I have checked which CPU is installed. It is a Pentium with 133 MHz.I could not find a download for a firmware update. Who can help and has the appropriate updates on disk? Which version is best for the ZVRE 1043.0009.50?Thanks for your help.PS: I make a backup of the hard disk and replace it with the CF card.
A-BF 3010MF PSU - Page 1
Forum section: electronics / testgear

author: oxygen
author_rank: Newbie
timestamp: November 17, 2023, 07:46:54 am
content: Hello,does anyone have experience with ABF-3010MF Power supply ?https://www.aliexpress.com/item/1005004269440877.html

author: oxygen
author_rank: Newbie
timestamp: November 23, 2023, 05:52:56 pm
content: Voltage and current readings are good enough.For 57$ works :-)Just unpacked it yesterday.Guess there is noise in the output.Cheap thin cables and crocodiles.
upcomming Rigol DG800Pro/ 900pro function gen? - Page 1
Forum section: electronics / testgear

author: elex_enthusiast
author_rank: Regular Contributor
timestamp: November 23, 2023, 11:10:30 am
content: Something caught my attention while "youtubing":https://www.youtube.com/shorts/OhlBgoj5Z50?feature=shareRigol seem to have upcoming "new" function generator and multimeter in the DHO800/900 form factor. I'm planning to acquire a function gen since I don't have one yet and this would be great if it performs better than its predecessor, bang per buck. Perhaps one might be on its way to Dave?

author: PELL
author_rank: Regular Contributor
timestamp: November 23, 2023, 12:38:42 pm
content: https://www.eevblog.com/forum/testgear/rigol-just-launch-its-new-function-generator-dg800pro-900pro/

author: elex_enthusiast
author_rank: Regular Contributor
timestamp: November 23, 2023, 01:41:35 pm
content: oopps! I wasnt aware there's already a thread for this topic. Thanks for pointing it out
Waveform Database? - Page 1
Forum section: electronics / testgear

author: kosmos
author_rank: Contributor
timestamp: November 27, 2023, 10:38:18 pm
content: Does anyone know of a waveform database? I would like to have some automotive waveforms for my DG1022Z. For example, the signal of an inductive crankshaft sensor 60-2, camshaft sensors,...Or maybe there is something to buy where you can perhaps extract the data. PicoScope always had a fairly large database, so it will probably all just be images.

author: rvalente
author_rank: Frequent Contributor
timestamp: November 28, 2023, 02:28:15 pm
content: Obviously is something really useful, have you tried matlab forums?

author: eospss
author_rank: Contributor
timestamp: November 28, 2023, 03:40:03 pm
content: I know some industrial databases. These databases are somewhat similar to clickhouse databases. Vertical retrieval, using timestamp + simple data as stored data. Very suitable for waveform display. And it is very small and can be used in SoC, but it is basically commercial software.

author: kosmos
author_rank: Contributor
timestamp: November 28, 2023, 07:03:22 pm
content: what is the name of this database.
Flir DM93-2 discussion and comparison thread - Page 1
Forum section: electronics / testgear

author: ballsystemlord
author_rank: Frequent Contributor
timestamp: November 20, 2023, 11:39:41 pm
content: Hello,I recently saw that Flir had released a new version of their DM93 and it's now available through tequipment.I thought it would be interesting to compare the two, so here goes.The DM93-2 is 136g, 0.33lbs, heavier than the DM93 (1.33lb/601g total for the new meter). It's also larger at 60.7x98.1x207.1mm (2.39x3.86x8.15in) vs. 52x83x188mm (2x3.2x7.4in).The new meter retains the notes where you have to add 10d-20d to the accuracy spec if you're measuring below 10% of the range, so it becomes far less accurate at lower readings. Likewise, there are still 1m and 10m time limitations to the Amp and mA ranges. The new meter is rated IP54 much like it's predecessor.The buzzer frequency has been increased from 2khz to 2.7khz. Why?The new DM93-2 lowers the amount of digits displayed for the frequency counter from 40K counts to just 4K counts.The capacitance accuracy has dropped on the 400.0nf range. Now you have to add 10d instead of 2d.The AC bandwidth goes from 20kHz AVC and 10kHz ACI to just 5kHz for both.So to me the new DM93-2 seems to be an overall downgrade to a meter that needed a few improvements to begin with (like allowing continuous current opperation).What do you think?EDIT: Got the user manual from flir official website and forgot to update my post to reflect this before submitting.EDIT2: Here's some links for you:DM93-2 FLIR webpagetequipment

author: ballsystemlord
author_rank: Frequent Contributor
timestamp: November 21, 2023, 01:36:32 am
content: PS: When I saw that the new meter was larger, I thought that maybe they'd increased the size of the batteries thus enabling more than 100 hours of lifespan. But no, the batteries are still 6 AAA.

author: ballsystemlord
author_rank: Frequent Contributor
timestamp: November 22, 2023, 11:55:54 pm
content: Oh, I forgot to mention the pricing!DM93: $393.99DM93-2: $419.99So the new meter costs $26 more at MSRP than the previous model.
recommendation variable hz/v AC bench supply - ITECH IT7321 or something else? - Page 1
Forum section: electronics / testgear

author: jpyeron
author_rank: Regular Contributor
timestamp: November 22, 2023, 03:23:02 am
content: I sometimes have a quick need to test some AC circuits. Was thinking this would be nice to have.Any thoughts? Suggest something either better or cheaper?ITECH AC Power Supply 300V/3A/300VA Programmable Bench Adjustable Single-Phase AC Power Source with Linear Amplification Technology Variable Frequency IT7321

author: coppercone2
author_rank: Super Contributor
timestamp: November 22, 2023, 03:35:51 am
content: a chroma would be like good. compare specs to chroma

author: jpyeron
author_rank: Regular Contributor
timestamp: November 22, 2023, 11:03:15 pm
content: Quote from: coppercone2 on November 22, 2023, 03:35:51 amLittle lost on their product line, but the Chroma 61605 is really nice - but not a justifiable budget.Did you have a specific model in mind?

author: coppercone2
author_rank: Super Contributor
timestamp: November 22, 2023, 11:05:25 pm
content: no they are kind of rare to stumble on but they are spoken of highlymains is kinda ugly and does not change much so they probobly stay in service until they break because people often just want sanity checks on inverter qualification. like people that need to import shady chargers for battery products or test inverters with loads. Because a special lab will test AC to death (safety qualification) but they usually want like a quick check to check if it works at all, so a chroma test bench does that pretty good with a program

author: jpyeron
author_rank: Regular Contributor
timestamp: November 22, 2023, 11:12:14 pm
content: have some end of year money, but not enoughapparently.

author: coppercone2
author_rank: Super Contributor
timestamp: November 22, 2023, 11:16:18 pm
content: use a variac? I would never buy that unless I was getting heavy into some really specific stuff, unless it was for workmost people will buy a drive, or use a variac.for mains SMPSU you could use a higher voltage power supply and skip the recifier bit and just work on the DC DC or DC ac converter.The things in front of the DC rail are hard and expensive to test IMO. Active rectifier is a interesting use that might benefit from a high end AC lab supply for DIY... and I guess the PFC.and I did not mean to get a chroma instead, I just mean that if you compare it to a chroma you see what its worth and if its highly deficient in anything. That supply is still really expensive (but I find mains extremely dull compared to something interesting like RF)
Fujitsu Denso EUL-75JL electronic load calibration - Page 1
Forum section: electronics / testgear

author: ARF
author_rank: Regular Contributor
timestamp: October 27, 2020, 11:25:04 am
content: I bought an old (2001) electronic load EUL-75JL.At first glance everything is fine, but the current meter has an error of about 100mA.The current meter shows 100mA in "HI" mode without load and 0.0357A in "Low" mode.The instrument has a calibration function and I am sure it can be corrected.I could not find user manual or service manual.The calibration menu has 31 items and without instructions it is impossible to understand what each particular item is responsible for.There are no variable resistors inside, completely digital design.Do you guys have any ideas?

author: ARF
author_rank: Regular Contributor
timestamp: November 07, 2020, 02:57:33 pm
content: Is there no solutions?

author: _Wim_
author_rank: Super Contributor
timestamp: November 08, 2020, 07:27:18 am
content: If you search forhttp://www.access.fujitsu.com/with the internet archive, you can find the original sites where this where sold. Together with automatic translation in your browser you might be able to find a manual.https://web.archive.org/web/20160417234435/http://www.access.fujitsu.com/

author: Madmanguruman
author_rank: Contributor
timestamp: January 14, 2022, 09:22:47 pm
content: Better late than never. Adding this in case someone stumbles across this thread.

author: DavidKo
author_rank: Frequent Contributor
timestamp: January 19, 2022, 08:11:19 am
content: I have tried to obtain the manual for EUL-150XL and it seems also as unobtanium. Fujitsu says Denso, Denso says they have nothing to do with it. By the search of internet archive (no pdf found) it seems that it was in Fukushima and the business was closed. I was able to find one name from internet archive in some other Fujitsu site and there was said that they no more support these products (they do another business).

author: ARF
author_rank: Regular Contributor
timestamp: April 05, 2023, 09:22:01 pm
content: So it is, the business was sold and in 2021 I managed to find who it was sold to and get instruction.I was able to successfully calibrate my device. It's pretty easy with the manual. I did it in 2021, but did not write back about the result.Link to the manual, I am sure that Japanese will not confuse anyone in the digital age.https://disk.yandex.ru/i/XTXZps8hEF4oNgThe manual is suitable for:EUL-75JLEUL-150JLEUL-300JLEUL-300JZEUL-75JHEUL-150JHEUL-300JH

author: lugaw
author_rank: Regular Contributor
timestamp: November 23, 2023, 01:27:31 pm
content: Thank you very much for this! I have two of this unit the 300 and 600watt version and has been searching for a manual. I was only using the GPIB commands and can't understand how to operate the front buttons. Now I can use the front buttons properly.
quiet fans - Page 1
Forum section: electronics / testgear

author: timelessbeing
author_rank: Frequent Contributor
timestamp: November 25, 2023, 06:18:58 am
content: In a recent podcast, Dave mentioned a forum discussion about some new Rohde & Schwarz equipment that has super quiet fans. I'm looking for some quiet case fans, but I couldn't find the topic. Anybody know what Dave was talking about?

author: magic
author_rank: Super Contributor
timestamp: November 25, 2023, 08:23:31 am
content: You could look into known-quiet test equipment, but you will likely find fans from little-known Far Eastern OEMs which may be difficult to source in low quantities outside Asia.For a 12V fan with reasonably common mounting hole arrangement you can always look for quiet computer fans. Plenty of those around, and plenty of reviews and user discussion. I have had good experience with Noiseblocker and Scythe fans - low noise, long service. And some mixed experience with cheaper ones.Another matter is how the equipment drives the fan. A loud fan is quieter if it's ran at low RPM, a good fan is louder when ran unnecessarily fast.
Measure AC voltage and Frequency with DAQ970A - Page 1
Forum section: electronics / testgear

author: Jeroen3
author_rank: Super Contributor
timestamp: November 11, 2021, 02:57:31 pm
content: I'm currently experimenting with a DAQ970 + DAQM901A acquisition system, and I was wondering if it is possible to perform an AC voltage measurement and frequency measurement on the same input channel within a scan.Anyone know how? Or do I have to wire up two channels?

author: threephase
author_rank: Regular Contributor
timestamp: November 11, 2021, 08:23:44 pm
content: I believe you can only ave one measurement parameter per channel so you will have to wire up two channels with the same signal and use one for voltage and the other for the frequency.

author: matches
author_rank: Contributor
timestamp: November 22, 2023, 10:20:17 am
content: Include the same channel twice with a different configuration.A bit late but maybe helpful for others having the same question.
Tektronix TDS 340A tips? - Page 1
Forum section: electronics / testgear

author: BoredFish
author_rank: Unknown
timestamp: November 23, 2023, 02:54:02 am
content: I just bought my first oscilloscope, a Tektronix TDS 340A, and need some tips for it. It's "for parts" but passes all self tests, was willing to take the gamble since it's cheap ($70 + $30 shipping USD), just missing probes, which I got some cheap-ish ones (adafruit). Planning on opening it up and cleaning all the plastics and cleaning out the floppy drive. Anything I should do while I'm in it? I'm pretty comfortable with doing some in depth repairs on it, and honestly would like to keep the CRT as it's got a certain vibe to it that I like, though it's a little dim so it might be going out. Also I am definitely keeping the floppy drive as long as it works, the sound of one really is what does it for me. Thanks in advance!
Another cheap dual scope - Page 1
Forum section: electronics / testgear

author: Me-Bristol-uk
author_rank: Newbie
timestamp: November 19, 2023, 02:38:00 pm
content: I've enjoyed reading through the threads on the cheaper Chinese scopes by the likes of Zeewei and Fnirsi and given in to the temptation to get a DSO2512G in the current AliExpress sale but have also noticed they've recently started selling an even cheaper (about half the price) dual channel model, 'Engineer' SC02 (there's also apparently a single channel SC01 but I've not seen that yet).This looks like a dual channel version of the DSO154 but with a proper case.Claimed bandwidth of either 2mhz or 10mhz (they claim 10mhz analogue and 2mhz actual whatever that means) and 50MS/s.Not the best in specs but if it meets them it's hopefully cheap enough to wipe out the market for the 200khz scopes that really are only useful as toys.Unfortunately not everyone has the space to set up and use an old analogue scope (I have a Tektronix 465B and 15mhz Iwatsu in the attic but not the room to get them out to use) or the money for a Rigol or better bench scope or even Owon handheld so there is a market fr these cheaper units that hide in a drawer when not in use

author: Me-Bristol-uk
author_rank: Newbie
timestamp: November 19, 2023, 02:44:12 pm
content: Oh and the DSO2512G is my third attempt at getting a budget DSO after building a DSO138 several years ago (recently found and tested to only be reliable up to 100khz not the full 200 and aliases badly if timebase is too slow) and upgrading that to a Velleman WFS210 which I've just discovered after reading the thread on here about that model that mine shares the reversed waveform problem (ringing on square waves is on right rather than left) and so far this little Zeewei is great compared with those.

author: Fungus
author_rank: Super Contributor
timestamp: November 19, 2023, 03:01:19 pm
content: Link to product?

author: Me-Bristol-uk
author_rank: Newbie
timestamp: November 19, 2023, 03:20:04 pm
content: Oh yes sorry,https://a.aliexpress.com/_mtBqeMcIt's also listed on Amazon and eBay but as usual AliExpress are cheapest.

author: Aldo22
author_rank: Super Contributor
timestamp: November 19, 2023, 03:43:55 pm
content: SCO_2_10M already has a threadhere

author: Me-Bristol-uk
author_rank: Newbie
timestamp: November 19, 2023, 03:45:28 pm
content: Thanks, that didn't come up when I did a search

author: Aldo22
author_rank: Super Contributor
timestamp: November 19, 2023, 03:47:17 pm
content: Quote from: Me-Bristol-uk on November 19, 2023, 03:45:28 pmYes, because the name and brand are not quite clear, you don't really know what to look for.

author: Me-Bristol-uk
author_rank: Newbie
timestamp: November 19, 2023, 04:30:18 pm
content: This appears to be the single channel SC01 version, unfortunately another variation of the 200khz toy scope though this one claims to do 500lhz.https://a.aliexpress.com/_mq00QHe
HP 3469B info? - Page 1
Forum section: electronics / testgear

author: PioB
author_rank: Regular Contributor
timestamp: November 19, 2023, 08:34:34 pm
content: I bought a HP 3469B with the dot-display from about 1974 and am waiting for receiving it. Unfortunately it comes without manual. I downloaded the manual from the keysight website, unfortunately it is a very bad spotty scan which makes it nigh on unreadable in parts. Does anyone have a neater pdf available and would be willing to share it? I intend on taking it apart and cleaning it when it arrives, it seems some capacitors might be at the end of their lives. "DC measurement works but takes some seconds to reach stable value, ohms take some seconds but then the values swings wildly, AC untested"...I'll post pictures (and probably questions) as soon as I have it in my hands.Best regardsPio

author: alm
author_rank: Super Contributor
timestamp: November 19, 2023, 09:41:36 pm
content: If you can't find a free copy, thenArtek Manualshas what I'm sure is a much better quality scan for $10.

author: factory
author_rank: Super Contributor
timestamp: November 19, 2023, 10:06:32 pm
content: The Artek 3469B manual is much better than the Agilent/Keysight crap.The digital panel meter part in the front is also known as the 3431, which was used in various other HP TE, it got updated to use normal 7 segment displays in the last version.David

author: PioB
author_rank: Regular Contributor
timestamp: November 21, 2023, 07:59:17 am
content: Thank you very much @alm, @factory, I bought the Artek manual and the scan is fantastic!Now waiting for the parcel to show up!
Anritsu MS2721A - Firmware update files - Page 1
Forum section: electronics / testgear

author: pamphonica
author_rank: Regular Contributor
timestamp: November 14, 2023, 08:05:47 pm
content: I've just got an Anritsu MS2721A (not the later 2721B) which is stuck at the boot (1.52) page, showing "Invalid OS Image".Any MS2721 gurus out there?I can set ethernet from the boot page menu. I can even retrieve a new firmware package and perform an emergency reload of the firmware update, via the Anritsu MST package and ethernet connection on both devices.But when the process (presumably successfully) completes, the device still re-boots into the boot page, not the main OS/application.The CF card is there, and contains quite a lot of files (looking like the correct set, based on the release numbers).But the CF contains only:Firmware Update folder: text file confirming MS2721A and update v1.74OS folder: Vxworks.binSys folder: all the expected files in app/base/bmp/wav folders.Usr folder: empty.And when I examine the zip file downloaded by the MST app, it does not seem to include an OS. But it does have a lot of other stuff, still the same versions as already on the CF.When I examine the MST files list document, it shows that there is no executable zip file.I finally tried copying the contents of the folders from the zip file downloaded by MST to the CF. But once again nothing useful happens.Could anyone let me have a copy of a working firmware files zip (OS1.52)? Or even a previous OS version that will run?many thanksJeremy

author: pamphonica
author_rank: Regular Contributor
timestamp: November 14, 2023, 08:06:58 pm
content: and the main boot menu page:

author: pamphonica
author_rank: Regular Contributor
timestamp: November 18, 2023, 07:48:53 pm
content: Ah - I had hoped that someone could help.Is there no-one out there with a working 2721A that could have a look and see which files are there?many thanksJeremy
Updated Aneng AN8002, calibration procedure? - Page 1
Forum section: electronics / testgear

author: pjwum
author_rank: Contributor
timestamp: November 18, 2023, 03:35:38 pm
content: Hi all,I never was really interested in those little Anengs, but now I got this updated black version of the AN8002. Its autoranging is really speedy and it is a nice little fun meter. It is well in specs, but when I tried to tweak a little more I found there is no EEPROM like in the old version and the PCB layout apparently has changed considerably. The calibration data might be stored in the main processor now? I tried the old AN8002 calibration procedure with bridging some of the solder joints but without success.Anyone has this new version and figured out how it is calibrated or which processor they probably use?Best,Patrick
Rigol DG1022U - latest known firmware and what U at the end really mean? - Page 1
Forum section: electronics / testgear

author: Velund
author_rank: Regular Contributor
timestamp: November 03, 2023, 04:17:33 am
content: Hello!Does anyone know, which latest version of firmware is exist for DG1022U function generator? I'm in doubt that the one I found for DG1000 series, with "HW v3 only" note, is really safe to try. Also, what that "U" mean, upgraded recalled early version, or something else?

author: sprint
author_rank: Newbie
timestamp: November 18, 2023, 06:25:32 am
content: maybe University
BK Precision 9140 Series Vs GPP4323 - Page 1
Forum section: electronics / testgear

author: Sariel
author_rank: Regular Contributor
timestamp: November 17, 2023, 12:11:00 pm
content: Hey everyone,I'm in the process of selecting a new power supply for my lab and I'm currently torn between the BK Precision 9140 and the GPP-4323 models.While the price difference is significant, the BK Precision 9140 series stands out to me with its compact 2U size, which is a perfect fit for my limited lab space. However, it only has 3 channels.On the other hand, the GPP-4323 offers four tunable channels with CC and can also function as a DC load, providing additional versatility.If cost isn't a limiting factor, which one would you recommend? Also, any insights on the perceived quality of BK Precision versus GW Instek? I'd appreciate your thoughts and experiences.

author: nctnico
author_rank: Super Contributor
timestamp: November 17, 2023, 05:25:03 pm
content: No hands on experience but possible the fan noise may be higher on a smaller unit. I also get the feeling the BK Precision 9140 is a switching PSU while the GPP4323 is a linear PSU for sure. For developing / testing analog circuits you will want a linear PSU because a switching PSU pushes too much noise into the circuit under test.
HP 3325A , Need Repair help - Page 1
Forum section: electronics / testgear

author: GigaJoe
author_rank: Frequent Contributor
timestamp: November 13, 2023, 07:01:19 pm
content: HP 3325A:errors on self test 2, 3 (seems misleading )Output on display: 29mV P-P:NOTE: Output not terminated to 50 Ohmscope CH1 AC , and DC are present from generator output at lower peak of waves ( like DC offset , but it OFF)output on display: 30mV P-P:same DC offset "0" at bottom of sinewayThen I shorted ACD ,all tests pass , 1V P-P , became 2.1V P-P unterminated , and everything works , butno DC offset regulationthis test pass with +20mV off:and im lost a bit , looking for direction ....Found - LM311 , A14 boardFixed , now it need adjustment ... calibration , at the level i can do ....

author: m k
author_rank: Super Contributor
timestamp: November 14, 2023, 09:35:29 am
content: Since triangle is based on square and square is based on sine one can expect the problem is quite far back.Since disabling Auto Cal removes the problem one can think that Auto Cal is the problem.Top is still round, so offset is available.Should peak detector find it during self test 1?Maybe it's just a timing thing.

author: m k
author_rank: Super Contributor
timestamp: November 17, 2023, 10:33:59 am
content: DAC to DC offset is controlled by HMD5 thru A14U29 as K5 to S/H latch A14U26 and strobed thru data decoder A14U27.K5 is also setting Preset Up/Down Counters A14U6 and U8.HMD5 is receiving level data thru A14U30.Div 3 relay pad out is controlled by K5 thru A14U30, so is ramp reset thru A14U1.Clearly K5 itself it most likely is not.Function selector A14U28 uses K0-4.After that actual "discrete" selector components are still many.DC Offset Control has only function enablers and Offset Error.Nothing that is directly ACD related.ACD is outputted to HMD3 with level data.So it is a digital info thing only and then is not controlling anything directly.
Best place to buy a new Rigol scope in the UK? - Page 1
Forum section: electronics / testgear

author: unknownparticle
author_rank: Frequent Contributor
timestamp: November 16, 2023, 09:34:39 pm
content: I've decided to buy a Rigol DHO924 scope and my initial market search in the UK shows a surprising lack of dealers! So, looking for recommendations for a good supplier and a heads up for any deals available.Cheers.

author: Mike99
author_rank: Frequent Contributor
timestamp: November 16, 2023, 10:16:24 pm
content: I've just bought a Siglent from Telonic in Wokingham. They also sell Rigol. Nice people to deal with and I got a small discount.Mike

author: themadhippy
author_rank: Super Contributor
timestamp: November 16, 2023, 10:39:02 pm
content: QuoteAnother vote for them,unlike some places they kept me informed about the progress of my order.The only thing to watch is they include a sales catalogue in with your order, tempting you with more shiny things to buy.

author: Mike99
author_rank: Frequent Contributor
timestamp: November 16, 2023, 11:25:06 pm
content: Quote from: themadhippy on November 16, 2023, 10:39:02 pmThey are local to me so I booked a visit. They have a demo room so you can try before you buy.Mike

author: heather
author_rank: Newbie
timestamp: November 16, 2023, 11:51:30 pm
content: I wanted to buy my 804 from Telonic but they had none in stock so bought from aliexpress as I was in a bit of a hurry for work. Ended up being significantly cheaper.But I bought some better probes and accessories from Telonic and they were very nice to deal with. Price was good and the stuff came the next day. The guy (i forgot his name) was very helpful on the phone.Is there even anyone else in the UK or Ireland distributing Rigol or just them? I see some on amazon but only a limited selection.

author: themadhippy
author_rank: Super Contributor
timestamp: November 17, 2023, 12:32:16 am
content: Quotetheres lamba in harpendenhttps://www.lambdaphoto.co.uk/
AC Picoammeter - Page 1
Forum section: electronics / testgear

author: slugrustle
author_rank: Frequent Contributor
timestamp: November 16, 2023, 07:42:38 pm
content: I'm working on design of a transformer with very low coupling capacitance between primary and secondary, intended for 30kHz sinusoidal voltage excitation, and I would like to measure the common mode leakage current through the transformer insulation. The current is anticipated to be quite low, maybe sub-nanoamp. It doesn't register on an Amprobe AM-140-A, so the leakage on my first prototype is <5nA if the meter is considered perfect.Is there an instrument made to measure AC current (at 30kHz or higher) with picoamp resolution? It strikes me that picoammeters are likely meant for DC or close to it.I suppose I could use an opamp like the LTC6268-10 (20fA input bias max @ 25°C, 0.45pF typical input capacitance) as either a transimpedance current sense amplifier or with a high shunt impedance and send the output to an AC millivoltmeter. I have a Tonghui TH1912A AC millivoltmeter, but the input impedance is 1MΩ in parallel with 30pF, so that would shunt a lot of the signal I'm trying to measure.I haven't thought of of other options for this.

author: TimFox
author_rank: Super Contributor
timestamp: November 16, 2023, 08:34:07 pm
content: One (un-cheap) off-the-shelf solution is a current-input preamplifier, of the type used with lock-in amplifiers, which can drive any normal AC voltmeter.Stanford Research Systems is a good (un-cheap) source:https://www.thinksrs.com/products/preamp.htmlThe SR570 is a free-standing (with AC power supply, also usable from battery) unit.The SR555 and SR556 are designed to be powered from a lock-in amplifier through a DSUB cable.These have different bandwidths (and the SR570 has selectable filters), and the input impedance depends on range setting (see specifications).I believe the inputs (virtual ground) are all DC-coupled, so depending on your application you might need a series capacitor at the input.In my university days, decades ago, I used similar units from Princeton Applied Research (PAR), which may be available on eBay.

author: slugrustle
author_rank: Frequent Contributor
timestamp: November 16, 2023, 10:18:55 pm
content: Thanks. SR555 looks like it would work for this, and they explain how to use it separately from a lock-in amplifier, which is nice. Also very cool that they show block diagrams in their manuals.Although, given the price, I'm pretty tempted to lay out a board in Rogers RO4350B with an LTC6268-10 (and maybe a post buffer amp), power it from 9V batteries and quiet regulators, and put it in a metal box. Doesn't need to be pretty.Come to think of it, I should probably run an impedance sweep on the AC millivoltmeter input before trying to hook a preamp up to it. Haven't had the occasion to do that to test equipment before, haha.

author: mawyatt
author_rank: Super Contributor
timestamp: November 16, 2023, 11:20:29 pm
content: You realize that 1pa at 30KHz is equivalent of 1V across 5.3aF, or 0.0053fF, or 0.0000053pF!!!Best,
Fluke 17B mV Input Impedance  - Page 1
Forum section: electronics / testgear

author: neikalo
author_rank: Contributor
timestamp: November 16, 2023, 06:56:33 pm
content: Can someone please tell me the measured input impedance of the 17B on the millivolt DC range? The manual indicates it should be 10 megaohms or so, but mine is beyond what I can measure accurately. Probably > 1 gigaohm.
Edgetech DewPrime II Hygrometer - Page 1
Forum section: electronics / testgear

author: Pete2
author_rank: Contributor
timestamp: March 21, 2023, 04:59:52 am
content: Hello!I recently acquired this very interesting test instrument: Edgetech DewPrime II chilled mirror hygrometer. You can find them on ebay for a couple of hundred dollars depending on condition. My unit seems to work or at least it powers on but I have no idea how to operate it since I can't find the manual for it and the menu system is not very clear since it uses 7-seg LED display for everything.I have contacted Edgetech several times and initially got an answer asking for the serial number but after that nothing. So I'm writing here to ask if someone has the manual for it or can tell me how the menu and settings work so I can test if it really works. Edgetech told me that the manual is specific to the model configuration but I think I can manage with any manual for the DewPrime II (or even DewPrime I). I can find a manual for the Dew Master but that's a completely different unit.

author: dcmxx
author_rank: Contributor
timestamp: November 15, 2023, 05:19:21 pm
content: Hi, i didn't saw this thread earlier.but i attach the manual here.i didn't have any problem to get it from edgetechyou will need an ambient temperature probe if you plan to use it for RH
Tektronix TDS5054 motherboard upgrade problems - Page 1
Forum section: electronics / testgear

author: andy2000
author_rank: Frequent Contributor
timestamp: April 11, 2019, 06:49:57 pm
content: I'm attempting to upgrade the ATX motherboard in an old TDS5054. The original is an Intel 810E based socket 370 board. So far, all attempts to use anything newer than a PIII generation board results in errors on POST and an ACPI related BSOD. Even attempting a clean Windows installation results in an error about the system not being fully ACPI compliant. Disabling ACPI allows installation, but that's not a usable solution.I've tried a number of motherboards including Core 2 duo, Athlon XP, and several P4 boards. I've even tried an i845 based board borrowed from a newer revision TDS5104 (not the B version). This board results in the error "PCI IRQ routing table error [02:0f:00]".I suspect Tektronix did something sloppy when designing the PCI acquisition interface board which conflicts with something in later ACPI versions. The newer scope has a different PCI acquisition interface board.The best I've been able to make work is an i815 board, which at least supports Tualatin PIII CPUs.Before I call it a day, does anyone have any ideas?

author: denimdragon
author_rank: Regular Contributor
timestamp: July 24, 2019, 10:37:43 pm
content: Quote from: andy2000 on April 11, 2019, 06:49:57 pmDid you ever figure this out?

author: uccoskun
author_rank: Newbie
timestamp: December 01, 2021, 05:12:09 am
content: I installed a intel i3 motherboard. (Intel DQ77MK Motherboard). It took 6 months on and off. It works no errors. I end up cutting the care to fit the connectors but it works. There is another thread here which I follow.I suggest you install drivers first on the mother board and then attach the tetronix board.

author: Joebeazelman
author_rank: Regular Contributor
timestamp: November 19, 2023, 04:49:25 am
content: Cool! Sorry to necropost, but I just started another thread on this topic. Feel free to chime in. Hopefully, we'll have a wiki on this scope.https://www.eevblog.com/forum/repair/help-with-replace-tektronix-tla5000tds5000-motherboard/msg5173095/#msg5173095
Another DHO800 to DHO900 Upgrade Query (DDR3L) - Page 1
Forum section: electronics / testgear

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 15, 2023, 10:44:48 am
content: we know there are 2 ddr3 ram missing in DHO800 and present in DHO900 DSO... we know the missing ic are GDP2BFLMhttps://www.gigadevice.com.cn/Public/Uploads/uploadfile/files/20230704/DS-00823-GDP2BFLM-Rev1.1.pdfbut its nowhere to be found in market, so i look if there's any compatible ram ic, i found this... footprint pads and ram size are compatible from my blunt eyes looking at datasheets.https://my.element14.com/integrated-silicon-solution-issi/is43tr16256al-125kbli/dram-256m-x-16bit-bga-96/dp/2787047can i just buy it and install it on DHO800 and hope it can work? i hardly can read any timing and procedures in there, so asking if any DDR3L guru here, can we exchange them like we exchange batteries of different brands as long as same voltage. like we exchange opamp of different models as long as very close spec and footprint and opamp count etc?