hybridfree/eevblog-posts huggingface dataset:
Looking for someone with a Metrahit Cal to check something - Page 1
Forum section: electronics / testgear

author: Magnum
author_rank: Regular Contributor
timestamp: December 11, 2023, 07:18:50 pm
content: Hello,I have a Metrahit Cal Calibrator which has a software problem:When the unit switches off (or is manually switched off with the on/off button) while simulating Type K Thermocouple Temperatures it will switch to Type B Thermocouple when turning it on again. I have a quite old unit with firmware 1.15 and Gossen confirmed the software problem. But they can't tell me if it was fixed with a later firmware version.So before I send the unit to Gossen for the firmware upgrade I would be very happy if someone, who has a Metrahit Cal with a firmware > 1.15, could check if that problem is still there.Many thanks,Magnus

author: RobinLox
author_rank: Newbie
timestamp: March 19, 2024, 04:43:00 pm
content: Hello there, I just tried with a Metrahit CAL with Software 2.32 (which is the most recent one) and unfortunately the bug still persists.
HP8662A EFC socket - Page 1
Forum section: electronics / testgear

author: alan.bain
author_rank: Regular Contributor
timestamp: March 19, 2024, 04:34:47 pm
content: Does anyone have a photo showing the EFC socket on the rear panel of an HP8662A for fine tuning the 10MHz oscillator?I think it came with OPT 003 - Absolute Phase noise and I'm retrofitting to one without but would like to do so in a tidy manner and none of the manuals I have show where the socket was located (nor is there a suitable blanking plug for anything but the rear panel RF out),Alan
Loop calibrator - Page 1
Forum section: electronics / testgear

author: trevwhite
author_rank: Frequent Contributor
timestamp: March 19, 2024, 08:20:52 am
content: Hi AllI have found a few Fluke 705 loop calibrators on Ebay for a reasonable price. I trust a second hand Fluke over some other unknown new brands but looking to see if anyone else has recommendations. I will likely need to get whatever I buy calibrated. I have read some need to be returned to the factory for calibration which isn't ideal.https://cpc.farnell.com/multicomp-pro/mp700005/single-function-loop-calibrator/dp/IN08412?mckv=sN2QM5kjd_dc%7Cpcrid%7C426684131414%7Ckword%7C%7Cmatch%7C%7Cplid%7C%7Cslid%7C%7Cproduct%7CIN08412%7Cpgrid%7C100371162478%7Cptaid%7Cpla-883790730859%7C&CMP=KNC-GUK-CPC-SHOPPING-9262013734-100371162478-IN08412&s_kwcid=AL!5616!3!426684131414!!!network%7D!883790730859!&gad_source=1&gclid=CjwKCAjw7-SvBhB6EiwAwYdCAeqnorOEnVWysccAWTHlmgzlSMD_6RyO4u76hE8ju28WHCeDy4YwWRoC43QQAvD_BwEThanksTrev
HAMEG HM1000 - Vertical position knobs - Page 1
Forum section: electronics / testgear

author: ppTRN
author_rank: Regular Contributor
timestamp: March 16, 2024, 01:49:18 pm
content: Hi everyone,at work (a school) we have four HAMEG HM1000, dual channel 100MHz, and each one of them has problems for the CH1 and CH2 vertical position knobs. It is impossible to move up and down the traks, they move super slowly, or jumping up and down, or even stay complitely still, independently of the speed and pressure applied to the knobs.I didn't open any, but I think the knobs are not encoders since they turn very smoothly. Looks like infinite turn potentiometers.There is another identical knob used to change the track intensity and it works perfectly in all scopes.I really do not think that all they need is a spray of contact cleaner, it is a problem too targeted to them. Maybe software problem?If any of you had the same problem or have any idea of how to try to solve it, it would be really apreciated!PS: not the same oscilloscope, but similar. At the beginning of the video it clearely shows that moving the traks is very easy and smooth

author: DaJMasta
author_rank: Super Contributor
timestamp: March 16, 2024, 02:09:07 pm
content: Have you tried just exercising them a bit (rotating back and fourth a few dozen times)? It sounds somewhat similar to what the encoders on some early 2000s LeCroy scopes run into, where they skip steps so it can be difficult to control where the traces go. In their cases, using them usually helps recover some functionality, and the initial problem seems to have to do with being stored in a place with some humidity.

author: ppTRN
author_rank: Regular Contributor
timestamp: March 16, 2024, 02:13:11 pm
content: Hi,yes I tried to rotate them a few times but nothing really changed.On monday I will try to spry them with some conctact cleaner and see if that does something.Thanks for your answare

author: ppTRN
author_rank: Regular Contributor
timestamp: March 18, 2024, 06:10:06 pm
content: They were encoders and they were NASTY. I opened them and cleaned them all. They were full of grease for some reason and it must have become slightly conductive or some dust got stuck to it. Anyway after a good cleaning they works much better. Not as good as new tho. I think I will replace them as soon as I can.

author: EvgenyG
author_rank: Regular Contributor
timestamp: March 19, 2024, 01:15:55 am
content: You can order new ones fromhttps://www.sky-messtechnik.de/I've replaced all encoders in my Hameg scope and it works better than new now!
Sencore LC102 Display Shows "Short" - Page 1
Forum section: electronics / testgear

author: ScottSerpa
author_rank: Newbie
timestamp: March 21, 2024, 06:23:17 pm
content: I have an LC102 that I purchased new many many moons ago. I think I had it calibrated once by Sencore but other than that one time, it's been working fine. All of a sudden the display reads "Short" when testing a capacitor or zeroing "Open". I found L1 stuck, replaced it but that made no difference. I read 51 Ohms at the BNC so it's not an input short.
Double line Fluke - Page 1
Forum section: electronics / testgear

author: donescamillo
author_rank: Contributor
timestamp: March 17, 2024, 09:14:30 pm
content: Hello,Is there a Fluke DMM that, when measuring ACV, will show on one line the voltage and on another line the frequency, that is, you see simultaneously both the voltage and the frequency?Like, say, Brymen 869s?I looked at Fluke 287/289 manuals and sure they have big displays but you still have to press a button while measuring ACV to display frequency.

author: blue_lateral
author_rank: Contributor
timestamp: March 17, 2024, 10:59:58 pm
content: Not that it does you much good, but the Fluke 183/185 probably does. It is a rebadged Tektronix TX1/TX3. They are not easy to find in either brand, and tend to be expensive considering their age. When set to Volts, my TX3 defaults to ACV on the main display and Hz on the secondary display.

author: abeyer
author_rank: Frequent Contributor
timestamp: March 17, 2024, 11:08:35 pm
content: The 45 does and seems to be plentiful and cheap on the used market, but is a bench meter, not handheld.

author: bdunham7
author_rank: Super Contributor
timestamp: March 17, 2024, 11:37:02 pm
content: Do you want it to always display both by default and you don't want to press any extra buttons to get there? Or are you OK pressing buttons but you just want both values displayed at the same time?Both the 189 and 289 (and surely the 187 and 287) will display both values simultaneously, but not by default and Hz will be on the larger or primary display while VAC will be on the smaller one.

author: joeqsmith
author_rank: Super Contributor
timestamp: March 18, 2024, 01:51:33 am
content: Quote from: donescamillo on March 17, 2024, 09:14:30 pmAssuming that is a deal breaker for you, and you want a handheld, maybe something like the 120B.https://www.fluke.com/en-us/product/electrical-testing/portable-oscilloscopes/120b

author: donescamillo
author_rank: Contributor
timestamp: March 18, 2024, 05:16:11 am
content: I want both voltage and frequency displayed simultaneously without the need to press a button.

author: jfphp
author_rank: Regular Contributor
timestamp: March 18, 2024, 05:53:09 pm
content: Hello,Fluke graphical multimeter 867B -obsolete- A very powerfull multimeter...
Micronta multitesters video update - Page 1
Forum section: electronics / testgear

author: LektroiD
author_rank: Frequent Contributor
timestamp: March 15, 2024, 09:47:00 pm
content: If you've enjoyed my previous video you'll be pleased to know there is a part 2 in the making, which if I can source them all, will be filling in all the gaps of meters that were missed from the first video.just received 22-205 (shown in the video) and I've just snagged 22-209 from ebay, so the remaining meters are needed before I can complete part 2...(22 206)(22 207)(22 208)(22 213)(22 215)(22 216)If anyone has the manuals for 22-205, 22-209 and the Archerkit 28-4013, I would love copies of these. I think they are only a page or two, if you have these and don't mind taking a few minutes to scan them in it would be hugely appreciated; if don't have a scanner, a good clear photo with the phone would suffice, any help would be much appreciated..I'd also be interested in the meters prior to the catalog renumeration in 1974 for a possible part 3. I'm not looking for frebies as I've paid for all the meters up until now and will continue doing so, but if you are happy to donate, I'd be very happy to accept. Please message me if you have anything to offer. If you have any info on these, please leave a reply.

author: LektroiD
author_rank: Frequent Contributor
timestamp: March 17, 2024, 10:01:12 pm
content: Managed to snag a few more from ebay, just updated the list...
HP 226A Time Mark Generator - Teardown Photos - Page 1
Forum section: electronics / testgear

author: sean0118
author_rank: Frequent Contributor
timestamp: March 16, 2024, 05:35:22 am
content: Hi all,There doesn't seem to be many photos of the 226A online so thought I'd do a teardown. The service manual is available online but too large to upload here:A1 Inverter:A2 Trigger Generator:A3 Clock and Low Frequency Generator:A4 Clock and High Frequency Generator:A8 Filter:A5 2n Second Generator:A6 Motherboard:A7 Voltage Regulator (modified with extra capacitor??):

author: factory
author_rank: Super Contributor
timestamp: March 16, 2024, 12:25:22 pm
content: Quote from: sean0118 on March 16, 2024, 05:35:22 amVery interesting, I've failed to take pictures of mine.The serial number of your 226A is below 00100, it has been suggested numbers below 100 are from the prototype batch and full production started at 00100. The hand painted color stripes on the boards I've seen in prototypes before.The board mislabelled by HP as A1 in your pictures, is actually A9 in the manual, this is option 003, the program inverter board, most do not have this. Look nearer the start of the manual for this option.The extra capacitor, there are two chassis mounted capacitors in the manual, maybe someone decided it was easier to fit a replacement elsewhere, than try & get to those above the transformer, it looks too big to fit above the transformer anyway.David

author: sean0118
author_rank: Frequent Contributor
timestamp: March 17, 2024, 04:55:41 am
content: Quote from: factory on March 16, 2024, 12:25:22 pmInteresting! I didn't realise it was an early one, I noticed some of the boards have mods so could be a prototype.Quote from: factory on March 16, 2024, 12:25:22 pmThanks, looks like you are right and the board should be labelled A9.
Rigol DHO800/900 bugs - Page 1
Forum section: electronics / testgear

author: eTobey
author_rank: Super Contributor
timestamp: March 16, 2024, 07:53:47 am
content: I thought it would be a good thing, to create a list of bugs, so that user know what they buy, and rigol could fix things. Also other can try to recreate those.This is supposed to be alist of bugs, andNOTa diskussion.Please use for questions the private messages!Posts can then be updated/clarified (or deleted if proven no bug).Please add your model number!

author: eTobey
author_rank: Super Contributor
timestamp: March 16, 2024, 07:54:42 am
content: DHO814:Random triggers on single and timeout:It does it too, when in the ns scale, so there are no spikes to find.It happens after 1 to 5.7 seconds (4s average). Noise reject does not help, and changing the level has semingly no effect.

author: ebastler
author_rank: Super Contributor
timestamp: March 16, 2024, 08:25:39 am
content: There is an existing bug report thread:https://www.eevblog.com/forum/testgear/rigol-dho800900-oscilloscope-bug-reports-firmware/It has been littered with side discussions etc., so I understand the desire to have a "clean", bug reports only, thread. But I don't think the "no questions and discussions please!" approach is going to work. There will be unclear reports, false reports (operator error) etc., multiple people may have comments/questions/clarifications, and sorting all that out by PM will be a nightmare.If you want to put in the effort and keep an organized bug list, I would prefer the following: Allow discussions in the thread, but regularly update the first post to make it a concise, up-to-date list of known bugs. (And, ideally, bugs fixed in the various firmware releases -- Rigol's release notes are known to be incomplete.) Still a significant effort and commitment, but better than managing a very busy PM inbox, I think...Oh, and I would not bank on Rigol reading this thread, or even acting upon it. The only known instance where they responded to an EEVblog bug report was nine years ago, and that was in response to a very visible EEVblogvideoon PLL jitter.
Rigol DS1054z probe replacement - Page 1
Forum section: electronics / testgear

author: Adrian_Arg.
author_rank: Frequent Contributor
timestamp: March 15, 2024, 08:24:05 pm
content: Hello, I have to replace a probe on the Rigos DS1054z oscilloscope, and I wanted to know if this model would work well?https://es.aliexpress.com/item/4000057890455.html?spm=a2g0o.cart.0.0.66dd7a9dNnFmCl&mp=1&gatewayAdapt=glo2espModel: P2200-2pcsBandwidth:Rise time: 1.75nsDimming ratio: 1X/10XInput resistance: 1MΩ/10MΩ±2%Input capacitance: 1X:70pF-120pF, 10X:13pF-17pFMaximum input: 1X-200 working voltage (Vp-p), 10X-600 working voltage (Vp-p)Compensation range: 10-35 pFOperating environment: 0-50℃,0-80% RHStorage environment: -20-60℃,0-90% RHSize: 110±2cmWeight: about 150g/set

author: wasedadoc
author_rank: Super Contributor
timestamp: March 15, 2024, 08:48:21 pm
content: Yes.
Rigol DL3021 DC LOAD, Program to Variable Resistance from Constant Resistance? - Page 1
Forum section: electronics / testgear

author: Pato Madera
author_rank: Newbie
timestamp: March 13, 2024, 04:54:29 pm
content: We recently purchased a DL3021 DC Load, when it was powered on, then set to CR, the STATIC indication was on and the Knob and the adjacent control keys are de-activated, the STATIC indicator is now not lit, and the Knob and control keys are active after we tried to change to variable resistance by pressing various switches to see if it was possible, the load it now in a variable resistance mode using the Knob or control keys when in CR mode which we require for our purpose , the STATIC indication is not lit in the CC CV CP modes also, is there a toggle to turn off and on STATIC mode to use variable resistance mode. Unsure what switches we operated to turn off STATIC mode. Cannot find any reference to this in the user manual, and the Rigol help desk cannot answer my question. Our concern is if we do a Factory Reset or Firmware upgrade, we will not be able to select the variable resistance mode.

author: thm_w
author_rank: Super Contributor
timestamp: March 13, 2024, 10:35:02 pm
content: QuoteWhy would you be concerned about that?Please read the manual and it will explain how to use the unit:https://beyondmeasure.rigoltech.com/acton/attachment/1579/f-0777/1/-/-/-/-/DL3000_UserGuide_EN.pdf

author: Pato Madera
author_rank: Newbie
timestamp: March 13, 2024, 11:55:24 pm
content: Thanks for the reply, I can find no mention of using variable resistance in the Manual. We require variable resistance to test Battery Chargers to specification. and Constant current to discharge the installed battery. I am looking for a way to switch between STATIC and STATIC off, the Transient setting do not serve our purpose. At the moment is variable resistance in the CR mode with the static indicator off, I am trying to find out how it switched to variable resistance in the CR mode and will not switch back to STATIC mode and vice versa.

author: thm_w
author_rank: Super Contributor
timestamp: March 14, 2024, 12:47:58 am
content: Resistance is static, you set the resistance and then enable the load.If you want to vary the resistance you can either use remote control via a PC, or use the "List Operation Function (List)". Again, this is explained in the manual.https://www.batronix.com/files/Rigol/Elektronische-Lasten/DL3000/DL3000_ProgrammingManual_EN.pdf

author: Pato Madera
author_rank: Newbie
timestamp: March 15, 2024, 08:11:06 pm
content: I think my question is not being interpreted correctly, the information I require is not in the user manual. Daves' teardown of this unit shows the Static indicator unlit, and it is the variable resistance mode , just want to know how he got to that mode
Wavetek 75 vs 75a - what's the difference in these arb gens? - Page 1
Forum section: electronics / testgear

author: mr ed
author_rank: Regular Contributor
timestamp: March 10, 2024, 10:55:16 am
content: I can't find any info on the wavetek 75a arb gen , it's all about the 75 model in the docs.Anybody know anything?P.s. can someone read the socketed eprom? The firmware ID page says 75 or 75a so there is some difference.

author: mr ed
author_rank: Regular Contributor
timestamp: March 15, 2024, 10:23:24 am
content: Does anybody have any idea on what's different between them? The firmware startup banners are different so there must be something new in the 75a version.
What Cal Kit should I get - Page 1
Forum section: electronics / testgear

author: CrazyTiger
author_rank: Regular Contributor
timestamp: March 17, 2024, 07:58:59 am
content: I managed to get myself a fully working and tested, R&S ZNB8 VNA and a R&S ZVR. Over the last year, I managed to get from EvilBay R&S ZV-Z30 (3.5mm Cal Kit) and Maury BNC Cal Kit. The ZV-Z30 did come with a floppy with the cal files. The Maury Cal Kit however did not come with anything, it came pretty dinged up.Now I am looking for N type cal kit. This time around I am seeking for something new. I have come across few Chinese manufacturer making cal kits equivalent to Keysight 85032F. It turns out most of these Chinese Cal kits are more or less made by the same manufacturer.https://siglentna.com/product/f504ts-male-female-9-ghz-n-type-vna-calibration-kit/https://www.salukitec.com/sckcl09-n-mechanical-calibration-kit/(1050 USD)https://www.ugwave.com/562.html(900 USD)The saluki and ugwave specs are exactly same. UGwave is about 100usd cheaper.I have also considered getting an used 85032F, based on my personal observation with both the kits I purchased used, i never know what kind of abuse it has taken. I have seen total change of characteristic of open and short standard if its dropped, they will look pristine from the outside however.Any other cal kit I should consider?Anyone ever bought these Chinese cal kit?

author: tautech
author_rank: Super Contributor
timestamp: March 17, 2024, 09:48:03 am
content: Will you be using all N type cabling ?Many use the much more convenient SMA cabling and Cal at its termination nulling all cable and adapter effects.I went through this exercise and only ended up purchasing the F603FE Female 4.5 GHz 3.5 mm type VNA calibration kit for my somewhat basic needs.

author: CrazyTiger
author_rank: Regular Contributor
timestamp: March 17, 2024, 10:11:51 am
content: Quote from: tautech on March 17, 2024, 09:48:03 amYes, I will be using N connectors. Will be using it to characterize lots of cavity filters and couplers with N connector. What's your opinion on the F603FE?Another contender I am thinking is Dr. Kirkby's Cal Kithttps://www.kirkbymicrowave.co.uk/Sales-and-Services/Vector-network-analyzer-calibration-kits/N-calibration-kit/Its limited by 6GHz Load, dropped him an email sometime ago requesting 18Ghz variant/9Ghz, no news till date.

author: tautech
author_rank: Super Contributor
timestamp: March 17, 2024, 10:30:48 am
content: Quote from: CrazyTiger on March 17, 2024, 10:11:51 amIt suits my needs to its rated 4.5 GHz but push it higher and flatness is not so good. (SNA5014A)Comes in a sound wood box without a torque wrench however the more expensive kits do.Not 100% sure but think these might be of Rosenberger origin as they do make some cable assemblies for Siglent.Eg.https://siglentna.com/product/nm-smam-cable100cm18-ghz/At one time we didn't have definitions for Cal kits and they are still only generalised for each type.https://siglentna.com/wp-content/uploads/dlm_uploads/2023/08/Mechanical-Calibration-Kit-Datasheet_EN01A-.pdfP9&10
Rigol RSA3030 (RSA5065) Strange Behaviour at starting frequencies below 7.5MHz - Page 1
Forum section: electronics / testgear

author: AndrewJCS
author_rank: Newbie
timestamp: March 12, 2024, 11:00:17 am
content: I have today observed a really weird behavior in my Rigol RSA analyzer.For frequencies starting from 7.5MHz or lower, there is a sudden 5dB drop in the noise floor at EXACTLY 12.50MHz. The measured signal drops by half that or 2.5dB.This is independent of detector type (but significantly more noticeable on average or positive peak detectors). It is also independent of amplitude settings.It is driving me insane, and I wonder if any RSA owners out there could help me trying the same thing. Suggestion for setup is 100ms sweep, frequency span from 5MHz to 20mHz and auto RBW.This is an "upgraded" unit to 6.5GHz (so a 5065) and I wonder if that is part of the problem.Check pictures for details.Thanks!

author: KeBeNe
author_rank: Regular Contributor
timestamp: March 15, 2024, 04:16:56 am
content: Hello,this looks very much like a faulty flatness calibration
Cheap Power RF Amplifier 2-6Ghz for pre-compliance testing - Page 1
Forum section: electronics / testgear

author: implor
author_rank: Regular Contributor
timestamp: March 14, 2024, 02:10:03 pm
content: Is there any bang-for-the-buck brand with an power RF amplifier that can handle 2-6Ghz (or 3-6Ghz)?We already have gear to handle up to 3Ghz but now with updated standards we need to reach 6Ghz.However the field strength required is only 3V/m. So if it manage 10-15V/m we av golden.Any suggestions?
Ready-to-use DMM analog front end module? - Page 1
Forum section: electronics / testgear

author: jezel123
author_rank: Contributor
timestamp: March 14, 2024, 10:05:01 am
content: Hi everyoneI am planning to make a 5 digit bench DMM which uses Nixies for the display. Now, I don't have a lot of experiece when it comes to analog PCB design, and I would like to avoid wasting a lot of time and money on prototypes for the analog front end, so I thought, surely there have to exist some sort of ready-to-use precision DMM modules with simple serial communication, but I cant find any. It is entirely possible that I just don't know the terminology and am searching for the wrong thing.Best thing I found is a Cyrustek ES51997 IC, but I haven't found any reference design for it.Things I want to measure:Voltage (AC and DC) between 100uV and 240VCurrent (AC and DC) between 100uA to 2AResistance between 1 Ohm and 10MOhmCapacitance between few nF up to few mFDiode TestFrequencies between a few Hz up to 16 MHz (doesn't have to be precise)Thanks in advance!

author: iMo
author_rank: Super Contributor
timestamp: March 14, 2024, 10:13:10 am
content: Quote from: jezel123 on March 14, 2024, 10:05:01 amReady to use analog FE could be get from ADIhttps://www.eevblog.com/forum/metrology/adi-admx3652-6-digit-20-v-dvm/It is just an +/-20V FE, all others has to be created by you. Mind 5-6 digits with your above reqs is a pretty difficult project, imho.

author: Kleinstein
author_rank: Super Contributor
timestamp: March 14, 2024, 10:30:11 am
content: The DMM chip sets are usually made for lower resolution, not really 5 digits. They are build for low power, not high performance. This starts with a relatively low voltage range without a divider.The ES51997 seems to still use a dual slope ADC and would thus have a hard time to push it beyond is intended specs (60000 counts).There may be a different front end chip that could maybe be pushed to the 5 digit (99999 counts) range.I difficulty may be to get those more special chip in small quantety.There was such a board available:https://digilent.com/reference/add-ons/dmm-shield/reference-manual

author: jezel123
author_rank: Contributor
timestamp: March 14, 2024, 10:54:20 am
content: Quote from: Kleinstein on March 14, 2024, 10:30:11 amI know, that is why I find it surprising that there isn't any alternative to this.
(Solved) POLOSO RFNT-3 laptop battery tester manual and PC software please ? - Page 1
Forum section: electronics / testgear

author: Fraser
author_rank: Super Contributor
timestamp: March 10, 2024, 06:22:26 pm
content: Dear All,I have just purchased a used POLOSO RFNT-3 Laptop battery tester and it comes with everything except the power adapter, manual and PC software. The Power adapter is not a problem but I cannot find the user manual and PC software. The POLOSO web site appears to be downIf anyone owns one of these RFNT testers, please may I have a copy of the manual and software that was on the CD that came with it.Many ThanksFraser

author: Fraser
author_rank: Super Contributor
timestamp: March 11, 2024, 12:36:28 pm
content: Problem solvedA really friendly guy in Lebanon sent me the contents of the original CD this morningHe works in laptop/phone, wireless routers and gaming station repairs and could not have been more helpful when I messaged him asking for help. It is always nice to find a like minded person who is happy to assist others who they do not even know. I sent him a donation to buy some coffees by way of thanks.His MaTronix You Tube channel is to be found here…..https://youtube.com/@M0fix

author: rvalente
author_rank: Frequent Contributor
timestamp: March 13, 2024, 07:38:09 pm
content: Great, thinking about other guys which may have the same problem I hardly suggest to share the files in some drive.
DSView 1.3.0 - How to group channels into buss - Page 1
Forum section: electronics / testgear

author: paults1956
author_rank: Newbie
timestamp: March 09, 2024, 09:47:28 pm
content: The manual doesn't mention this AT ALL. I've tried clicking/dragging/chanting spells but nothing. What am I missing?? All I want is an 8-bit data buss and a 16-bit address showing the HEX values as my 8031 board runs BASIC from an EPROM.

author: abeyer
author_rank: Frequent Contributor
timestamp: March 10, 2024, 12:04:23 am
content: I think you want to add a parallel protocol decoder w/ your data and clock lines assigned in the config for the decoder. DSView is a custom build of the sigrok software, so you can always look at their docs for general reference, too, although there are minor differences.

author: paults1956
author_rank: Newbie
timestamp: March 13, 2024, 02:27:49 pm
content: Thanks! That was the method. Sure would HELP if it was mentioned in the manual.

author: asis
author_rank: Frequent Contributor
timestamp: March 14, 2024, 04:23:10 am
content: Hi,If you are working with DSLogic 16, you will have to divide its resource in half.That is, the first 8 bits are allocated to the address, using the zero bit for triggering, and the remaining 8 bits for data.You should follow the connection sequence - address/data bit size so as not to mislead yourself.Just practice in demo mode.
Wavetek 75 useful? - Page 1
Forum section: electronics / testgear

author: PwrElectronics
author_rank: Regular Contributor
timestamp: March 11, 2024, 06:00:36 pm
content: Have the opportunity to get a early 90s Wavetek 75 ARB. Is this useful to generate typical sine or square waves etc as-is or would I need to program it each time?For most uses I don't need the ARB functions and standard test signals are fine. But, the cost (free) is attractive...

author: theodoremoreau
author_rank: Newbie
timestamp: March 12, 2024, 08:11:26 am
content: You dont need to program it each time and as you dont need the ARB functions it could be an usefull tool for you.

author: ch_scr
author_rank: Frequent Contributor
timestamp: March 13, 2024, 07:21:48 am
content: They are pretty cool units, but the ARB waveform editing is designed to work in conjunction with an analog scope in X-Y mode with intensity modulation (sometimes called the "Z input" on the back of the scope). If you have one like that at hand, well worth it, even if just to "have a play".

author: egonotto
author_rank: Super Contributor
timestamp: March 13, 2024, 11:17:48 pm
content: Hello,what happens to the device if you don't take it?Best regardsegonotto
KEYPAD for R&S SFU 2110.2500.02 - Page 1
Forum section: electronics / testgear

author: OliverWirthg
author_rank: Contributor
timestamp: March 13, 2024, 12:22:43 pm
content: Is it possible to buy a new rubber keypad for the R&S SFU 2110.2500.02 somewhere? I have been checking ebay on a regular basis, but to no avail. Does anyone have an idea who to approach? Respectively, is it possible to search under a name other than "keyboard on R&S SFU"? Thank you for any help!

author: wraper
author_rank: Unknown
timestamp: March 13, 2024, 12:32:03 pm
content: For such things chances are essentially zero unless manufacturer is willing to sell it to you. What's the problem with original one?

author: OliverWirthg
author_rank: Contributor
timestamp: March 13, 2024, 05:36:59 pm
content: There is one missing on the original buttons. The others work unreliably (worn conductive surfaces).

author: wraper
author_rank: Unknown
timestamp: March 13, 2024, 08:54:49 pm
content: Poorly conductive surface usually can be restored by washing with detergent and if it's not enough, a little bit of sanding with fine sandpaper. Resistance can be checked with multimeter.
Homemade inexpensive AM FM sweep and alignment instrument. This looks pretty goo - Page 1
Forum section: electronics / testgear

author: Ned123
author_rank: Newbie
timestamp: March 13, 2024, 02:43:28 am
content: I posted this to see what you all think of it.https://www.nutsvolts.com/magazine/article/build-a-vintage-radio-sweep-alignment-instrumenthttps://www.nutsvolts.com/magazine/article/build-a-vintage-radio-sweep-alignment-instrument-part-2#

author: penfold42
author_rank: Newbie
timestamp: March 13, 2024, 11:43:44 am
content: excellent articles and excellent project!
Tektronix TDS2002B display replacement with a TDS2012 display, it's possible? - Page 1
Forum section: electronics / testgear

author: CharlieD
author_rank: Contributor
timestamp: March 02, 2024, 06:30:45 pm
content: Hi everyone.I need a display replacement for my Tek TDS2002B scope and I have an offer nearby of a TDS2012(With no B) display, its is possible to use the display of one model in the other? Is fully compatible between models of diferent revisions? If anyone has done this before please leave your toughts.It is impossible for me to try and see if it works, and then return if not, that's why I ask here beforehand, and the price is cheap, but not that cheap.

author: tautech
author_rank: Super Contributor
timestamp: March 02, 2024, 07:43:41 pm
content: What's wrong with your existing display ?Is it physically broken or just blank/black ?Have you tried the torch trick to ascertain if only the backlight is gone ?In the past I had a Tek that the backlight inverter stopped working due to the RC controlling the inverter switching went ouuta limits.... well the C, 220nF IIRC drifted to pF territory and the poor transistors couldn't keep up.Cheap fix and then flicked.

author: CharlieD
author_rank: Contributor
timestamp: March 12, 2024, 06:23:03 pm
content: Quote from: tautech on March 02, 2024, 07:43:41 pmThe display has a bad polarizer filter, and If I have the oportunity of change the display (cheeply) I'll go for it, and then with one good display I'll maybe change the polarizer and keep that display for parts or sell it.But I don't know if the displays of diferents revisions are interchangeable.
Recomendation for Lithium battery tester - Page 1
Forum section: electronics / testgear

author: seratester
author_rank: Newbie
timestamp: March 11, 2024, 04:10:41 pm
content: Hello!I need a lithium battery tester for mobile phones and laptops. I want to measure resistance and capacitance (not just readed capacitance from BMS) .

author: bateau020
author_rank: Frequent Contributor
timestamp: March 12, 2024, 10:30:07 am
content: Quote from: seratester on March 11, 2024, 04:10:41 pmYou probably mean capacity and not capacitance.Capacity can be measured most easily with any good charger. The SkyRC MC3000 is quite versatile in that respect. You can also go DIY and use a charger and a separate load, plus calculations. Seehttps://www.lygte-info.dk/for example.The resistance is more complicated, as there are many types of resistances/impedances in batteries. Search for "Combined Randle and Warburg Circuit Model" or "Equivalent circuit model".Different testers exist to measure the different impedances of Lithium batteries, in a wide price range. The one I made is here:https://github.com/hb020/batterymeter.You can also look in thehttps://www.eevblog.com/forum/renewable-energy/section of this forum.

author: seratester
author_rank: Newbie
timestamp: March 12, 2024, 02:19:53 pm
content: This kind of chargers like SkyRC MC3000 can be used with mobile phone batteries if i connect "+" & "-" only?

author: bateau020
author_rank: Frequent Contributor
timestamp: March 12, 2024, 02:45:21 pm
content: Depends on the battery. Some batteries use extra contacts for extra functionality/protection.Also, be aware that very few chargers that are made for cylindrical cells, also have the possibility to connect external temp sensors. A temperature sensor will allow you to do safer charging (I'd recommend that with dV/dt charging). I have a recollection of the MC3000 supporting it, but can no longer find proof of it. So you may be better off with other chargers or go DIY.
Uni-T UTS1032T spectrum analyzer, Trash or hidden gem? - Page 1
Forum section: electronics / testgear

author: implor
author_rank: Regular Contributor
timestamp: March 13, 2024, 01:24:53 pm
content: Supprised with finding nothing about this unit on the forum.It's a real-time 3.2Ghz spectrum analyzer with TG for as low as 1300 euro.Bargin or am I missing something?https://eleshop.eu/uni-t-uts1032t.html

author: TopQuark
author_rank: Frequent Contributor
timestamp: March 13, 2024, 01:59:51 pm
content: Quote from: implor on March 13, 2024, 01:24:53 pmIt says it is a RT spectrum analyser on the webpage, but nothing in the actual spec sheet mentions anything about real time capabilities, nor was the real time bandwidth spec mentioned anywhere?Also for the 3.2G model the TG has a lower frequency limit of 10MHz, which is a bit limiting. The product listing seems a bit all over the page, consistent with my past experiences with UNI-T products.

author: DaneLaw
author_rank: Frequent Contributor
timestamp: March 13, 2024, 06:57:30 pm
content: Promo video(from the link)
Is My GPSDO DOA? - Page 1
Forum section: electronics / testgear

author: NT0Z
author_rank: Regular Contributor
timestamp: March 03, 2024, 01:44:04 am
content: Hi, gang,Last year, a friend gave me an older BG7TBL-style (a rare generic variant/clone with Trimble innards) GPSDO, and I went through the learning experience of figuring out how to set up and use Lady Heather, get the unit talking on the serial ports, tweak the cfg file, and connect the 10-MHz ref output to my older HP 5328A counter.For several months it all worked perfectly.But recently, when I switched on the counter, it showed "all 8s" on the display when the external reference was selected (works fine on the internal reference). I looked at the schematics and consulted a few online helpers, who suggested that the HP may have a bad diode or two (CR5 and CR6), or a bad IC (SN7413N) near where the external ref is connected and switched between int/ext.Tonight I popped the covers and used a scope to see where my external ref signals might be going south. To my surprise there was no 10-MHz signal at all, and a test of the GPSDO showed no output on either 10-MHz output (although the 1PPS is still active).I connected a separate 10-MHz XTAL Reference oscillator (1.8 Hz low at 10-MHz at last check) to the external ref input, and the counter still shows all 8s when switched to the external reference and still works normally when using its internal oscillator. Using the scope I traced the temporary ref oscillator input to the junction of CR5 and CR6, and to the input pin of U16. I didn't trace farther because I'm not ACTUALLY sure what I'm doing.NOTE: I had to remove the HPIB board (option 11) to access the main board and the parts mentioned earlier. I didn't reinstall because I will never need the functionality, and the HP manual suggests that it won't affect anything whether it's in or out. I guess this could be incorrect, but the behavior of the counter seems identical either way.So, now I have a working counter that can no longer use an external ref, and a GPSDO the works fine from the PC and satellite side of the house (Lady Heather shows "lock" and strong signals from 7-10 birds), but has no 10-MHz outputs.Suggestions?As always, thanks,Kirk, NT0Z

author: GigaJoe
author_rank: Frequent Contributor
timestamp: March 11, 2024, 08:47:28 pm
content: gps blow up your counter's inputgps:10M out usually started at OCXO, so some pin should generate 10M output , if it "locked" and 10M out exist, you may tap from that pin, over cap and some resistor ( to be safe) ; or follow where it stops ...for a counterno clue , but follow the input , maybe something fail ; service manual usually help:https://www.keysight.com/us/en/assets/9018-05738/service-manuals/9018-05738.pdf

author: ddosegov
author_rank: Contributor
timestamp: March 11, 2024, 10:51:32 pm
content: Quote from: NT0Z on March 03, 2024, 01:44:04 amService manual, scope, inputs and outputs of U16 and U17...Diodes are there to limit input signal to TTL levels. In one switch position CR5 should be shorted...
Agilent 54642D/54600 series Font panel board - Page 1
Forum section: electronics / testgear

author: polymood
author_rank: Newbie
timestamp: March 11, 2024, 02:25:26 pm
content: Hello,I am in the process of repairing an Agilent54642DMSO that I bought on ebay.I am struggling to find information on the front panel board since my unit is missing it, I have no keyboard.I might try to recreate the board myself since I can't event find a replacement part anywhere.I am hoping someone has photos or maybe even schematics of a54642Dfront panel board or for the54600series.I am going to make a full repair forum post for this repair projectHere is the photo from the ebay listing :
Is the Hantek 6254BD the right choice for logging data on a robot?  - Page 1
Forum section: electronics / testgear

author: juchong
author_rank: Newbie
timestamp: March 11, 2024, 06:40:16 am
content: Hi! I'm looking for a solution to log a few voltage rails on a mobile robot. The robot is not tethered, so I'll need something that can be battery powered. The Hantek 6254BD seems to fit that requirement, but the software interface is very old. The system will need to measure 0V ~ 20V signals. A built-in battery is a bonus and not a requirement.

author: coromonadalix
author_rank: Super Contributor
timestamp: March 11, 2024, 11:03:57 am
content: and the qty of signals measuredsimple arduino / stm32 project(s) could do, even add external multiple inputs adc boardeven some mcu board with wifi ??i personally would avoid this brand
Digitech QC1933 Scope - Page 1
Forum section: electronics / testgear

author: BradC
author_rank: Super Contributor
timestamp: January 06, 2024, 07:32:17 am
content: G'day all.I've inherited a "Digitech" QC1933 scope. It didn't come with documentation and while it's relatively easy to use there's still some stuff I can't quite figure out (like if I can delay a trigger).I've combed the net and turned up nothing other than it looks like it was once sold by Jaycar. As such, it'll be a re-badge, and having a browse of scope UI images it looks closest to a Siglent.Does anyone recognise it and possibly have a lead on any documentation?I do have a Tek 2440 which does everything I need it to do, but this seems like it might be a bit of a simple go-to for a quick measure, and it can screen capture (which I can only do on the 2440 by pretending to be a HP printer over GPIB).

author: tautech
author_rank: Super Contributor
timestamp: January 06, 2024, 08:15:38 am
content: Try SDS1102CA5” display and IIRC 40kpts mem depth.If 2M memory it’s a SDS1102CM.Either way the UI is the same.

author: BradC
author_rank: Super Contributor
timestamp: January 06, 2024, 02:10:19 pm
content: Quote from: tautech on January 06, 2024, 08:15:38 amAwesome, that put me on the right path. It's not a Siglent, it's an ATTENADS7102CAADS2102CA. Now I can see if I can find a better manual. The Siglent manual has all sorts of firmware options the ATTEN doesn't have.Ta!

author: Stuart Coyle
author_rank: Contributor
timestamp: March 11, 2024, 05:11:03 am
content: I know I'm a bit late to the party, but I have one of these scopes with a manual. I can get it scanned if you have not found anything else.

author: BradC
author_rank: Super Contributor
timestamp: March 11, 2024, 08:04:48 am
content: Appreciate the offer Stuart. I managed to locate a printed copy. Still getting used to the trigger system, but it does the job.
Capacitor fluke 177/179 - Page 1
Forum section: electronics / testgear

author: ruisantos
author_rank: Newbie
timestamp: March 10, 2024, 03:07:57 pm
content: Hello,I needed to know the value of the capacitor (marked in the photo), just below the "Common" terminal.Does anyone know which one it is?I recently acquired a Fluke 177 which had liquid damage, I washed the board, but with the corrosion this capacitor, and the transistor, and inductor, came loose. I managed to solder these back on, but the capacitor was in very bad condition, so I needed to replace it with a new one, but I don't know how much it costs.Hug from Portugal

author: AVGresponding
author_rank: Super Contributor
timestamp: March 10, 2024, 08:59:30 pm
content: That "transistor" is more likely a BAV199 dual diode. Those components are part of the lead/jack sense, there's no schematic for the 179 that I'm aware of, but the one in the 87V is 0.01uF. The voltage rating shouldn't matter too much, as one half of that BAV199 clamps it to ~0.6V anyway.

author: mqsaharan
author_rank: Regular Contributor
timestamp: March 11, 2024, 07:33:49 am
content: Hi Ruisantos,Search the forum for 77-IV schematic and the details are in there.The Capacitor is 10nF 50V and i think it will be X7R type at least. Interestingly, these parts are not installed in old 177/179 multimeters.

author: Ugur
author_rank: Regular Contributor
timestamp: March 11, 2024, 08:00:49 am
content: transistor 2N3904Capacitor 0.01uF
Which budget/mid-range AWG? - Page 1
Forum section: electronics / testgear

author: Giallograle
author_rank: Contributor
timestamp: March 08, 2024, 05:34:27 pm
content: I'm a hobbyist looking for my first, preferably 2-channel waveform generator to use with my oscilloscope which will probably be the Siglent SDS804X HD.It's principally for use with audio circuits. The ability to connect it to the SDS804X for Bode Plots looks like a plus; there is software on Github which offers this for some non-Siglent AWGs and looks as though it could be extended to the Uni-T or others.I'm on Linux and happy to use my laptop also if it's useful for data analysis - in fact I'd probably prefer it for keeping things organised. Although I'd prefer not to have to use Windows software too much.Devices I'm considering (prices are ex-Vat) include:Uni-T UTG962E ~€140 14-bit 2-channelsSiglent SAG1021I ~€140 14-bit 1-channelRigol DG812~€240 16-bit 2-channelSiglent SDG1032-X ~€290 14-bit 2-channelsThe Uni-T looks like a lot of bang for the buck and probably fine for my purposes. The Siglent looks like an easier match with a Siglent oscilloscope, and a better unit overall which will probably do me indefinitely. It's at the top of my budget.I'm open to any other suggestions and I'd appreciate your comments or thoughts on the choice.Only other question is - all these units are quite a few years old - is there any likelihood that they will be updated anytime soon?Thanks!John

author: AVGresponding
author_rank: Super Contributor
timestamp: March 09, 2024, 10:05:34 am
content: You might want to consider what the support is like for the products you're looking at as well.

author: artur0089
author_rank: Contributor
timestamp: March 09, 2024, 07:36:55 pm
content: Quote from: Giallograle on March 08, 2024, 05:34:27 pmThe noise level of budget oscilloscopes and generators at a voltage of 1 Volt is -65 dB.Maybe it's better to use a good external sound card for PC and software (SpectraPLUS or RMAA)?

author: Giallograle
author_rank: Contributor
timestamp: March 10, 2024, 05:47:52 pm
content: Thanks for the advice.I have a Motu M2 DAC (-110dB noise, up to 192KHz) which I used with REW to measure my speakers so I'm familiar with it.Would REW's square and sine waves from the Macbook be good enough for this? I think some people still use an external signal generator for this.Are there any disadvantages or limitations I should be aware of? I think the usable bandwidth will be limited to around 44kHZ by the DAC.

author: TomWinTejas
author_rank: Regular Contributor
timestamp: March 11, 2024, 06:12:52 am
content: I'm a complete newbie, so take this with a grain of salt, but I believe if you pair a Siglent AWG with your Siglent scope that Bode plots will be easier to generate if that's important to you.
230V Variable Isolation Transformer - similar to Sencore PR570 - Page 1
Forum section: electronics / testgear

author: tochnia
author_rank: Newbie
timestamp: March 09, 2024, 10:40:47 pm
content: Does anyone know for any good /not Chinesium/Variable Isolation Transformerfor 230V?Similar to Sencore PR570... but with right voltage for UK

author: johansen
author_rank: Super Contributor
timestamp: March 10, 2024, 11:39:41 pm
content: I can't find anything for 230v other than some evidence that variac dot com made a 240v: 120-240v isolation variable transformer. but its not on their website, just this document.https://variac.com/staco/PDFCutSheets/VT%20isolated.pdfI could make you one, i've wound a 0-140v variac from 15 gauge wire and it was rather easy, with a little more effort i would have had it done right. i wouldn't be able to do the special silver-cadmium? plating that they put on top of the copper to make the brushes last longer and not corrode. actually, i wonder how long nickel plating would hold up... i wouldn't really be willing to do anything smaller than 15 gauge wire so you'd be looking at a 20 pound transformer..but for less money and shipping you can just buy yourself a 0-260v variac and a 230v isolation transformer.this is the only isolated variac i know of that's not 1500 bucks from stacko or variac assuming they even have one in stockhttps://www.amazon.com/Variable-Transformer-1000VA-Isolated/dp/B09X153FZWalso a serious question is how much granularity you want. -i have seriously thought about winding a variac which exposes every other turn, meaning a 4 layer inner diameter coil and a 2 layer outer diameter.a 20 gauge secondary coil (typically used on 5 or 6 amp rated variacs) spanning 180 degrees of the toroid would leave plenty of room for the 230v primary winding to go on the other half of the toroid. -its still going to be a pretty big transformer to fit a traditional single layer 230v winding on half or 2/3rds of the core.

author: Kean
author_rank: Unknown
timestamp: March 11, 2024, 02:12:57 am
content: Quote from: johansen on March 10, 2024, 11:39:41 pmYes. I believe when this topic has come up before, the general consensus has been to get a separate variac and isolation transformer.There are a lot more available options that way, and you can select based on your desired power requirements and build quality.