hybridfree/eevblog-posts huggingface dataset:
Stackable plugs on test leads - Page 1
Forum section: electronics / testgear

author: Cymaphore
author_rank: Regular Contributor
timestamp: June 22, 2021, 09:16:12 am
content: Hi,I want to share with you a very small modification done to some of my test leads. That modification had a high impact on my debugging and developement experience in the field, especially in and around vehicles.Attached you see some test leads, where I replaced the default shrouded plugs by Stäubli (MC) SLS425-SE/M stackable shrouded plugs. I picked them explicitly because they have a screw terminal and good strain releave. Originally I have done this at the workplace on a couple of old fluke probes with damaged plug to make a repair with improvement. But it quickly turned out how usefull this modification is (but mostly for probes with 4mm banana-style tips).Please keep in mind that this modification potentially can de-rate the safety of the test leads, based on the rating of the connector used and the open 4mm hole of the stackable plug.All in all this allows me to have a DMM sit at some central point while at the same time I can just plug in to the potential it monitores without much effort, effectively elliminating a lot of the usual cable mess.Maybe someone here has similar ideas about test cables in field usage and how to combat the rats nest.Best regards,Martin

author: wizard69
author_rank: Super Contributor
timestamp: June 23, 2021, 06:54:59 pm
content: Nice idea!That could be very useful for common connections across multiple instruments.
Fluke 87 DMM Bug when exiting continuity mode. - Page 1
Forum section: electronics / testgear

author: --Oz--
author_rank: Regular Contributor
timestamp: June 23, 2021, 07:28:50 pm
content: Fluke DMM Bug, Models: 87-1 & 87-IIIThe BUG:Select ohms on the dial (preferably connect a resistor above 500 ohms for a reference), then go into continuity mode by pressing the button, when switching out of continuity mode (by using the button, not rotary dial) and back into ohm mode, ohms does not read above ~500 ohms, it just reads open (it's stuck in 400 ohm range used in continuity mode). Under ~400 ohms it reads correctly.Turning the selector to another mode and back to ohms fixes the issue, it's not a big deal, but it can be giving you wrong info which does not help troubleshooting. This was tested on several 87-1 and 87-III meters with the same results. Its a small bug with easy workaround "if you know" the issue.The 87-V does not have this issue. On the 87-V, you can see the LCD screen flicker when its resetting the ohm range (fixing the bug).Here is a video I made testing four 87's.If anyone else tests this on their 87-1 or 87-3, please report back their results.

author: bdunham7
author_rank: Super Contributor
timestamp: June 23, 2021, 07:38:34 pm
content: Did you notice that the AUTO indicator doesn't reappear? So selecting continuity switches to the lowest ohms range and turns on the beeper. Turning off continuity disables the beeper but leaves it in the lowest manual ohms range. That's a pretty mild bug.

author: --Oz--
author_rank: Regular Contributor
timestamp: June 23, 2021, 08:08:32 pm
content: Yes, its mild, until your troubleshooting and your going off in a tangent because of the wrong info its telling you, dont ask how I know, hahaIt should go back to auto mode (if it was in auto), thats why they finally fixed it on the 87-5. Thanks for your reply.

author: floobydust
author_rank: Super Contributor
timestamp: June 23, 2021, 08:41:54 pm
content: In testing S/W you'd look for the same issue (did not remember previous range/function/mode) in other places.If you were on manual range ACV, then pushbutton to FREQ or %, what does that then take you back to as you toggle it? It's only important really if you end up in an unsafe mode/range.

author: BeBuLamar
author_rank: Super Contributor
timestamp: June 24, 2021, 02:27:38 pm
content: That's not a bug! You may not like it but not a bug. It's no more different than the 87V default to AC current.

author: Monkeh
author_rank: Super Contributor
timestamp: June 24, 2021, 03:13:30 pm
content: Quote from: BeBuLamar on June 24, 2021, 02:27:38 pmYes Fluke fanboy, it's a bug. Switching to continuity mode and back should not leave the meter sat in a fixed range.It's not a bad bug, but it is a bug.

author: --Oz--
author_rank: Regular Contributor
timestamp: June 24, 2021, 05:45:39 pm
content: Quote from: BeBuLamar on June 24, 2021, 02:27:38 pmPatato PatatoThen why does the 87-5 "fix" this "not a bug"?I think its a bug, I was not in a fixed range on ohms, and then it puts it in fixed range. I am only posting this for other to not be sent down the wrong rabbit hole, knowing the issue can save time.Quote
HP 1722A Scope time base knob assembly - Page 1
Forum section: electronics / testgear

author: just me
author_rank: Contributor
timestamp: June 22, 2021, 05:11:31 am
content: Hello.I have a HP 1722A scope that is missing the complete time base knob assembly.The scope seems to work and I'm trying to fix it for cheap.I've spent hours,it seems like,searching eBay and the internet searching for the knob assy.Any help would be greatly appreciated...

author: rf-messkopf
author_rank: Regular Contributor
timestamp: June 22, 2021, 11:56:45 am
content: If you look at the part numbers of the individual parts of the TB knob assembly, most of them are identical with other scopes of the series, e.g. the 1740A, 1741A, etc. In particular, is true for the two knobs (Main TB and Delayed TB). Since you still have the dial with the delayed TIME/DIV decal (the 1740A, etc., have different TB settings) as well as the two shaft assemblies, getting the two knobs from a 1740A or similar might be enough.I have an old 1740A parts donor sitting in the basement. However, I don't know if its TB knobs are still okay, and whether shipping from Germany would be economical.

author: just me
author_rank: Contributor
timestamp: June 22, 2021, 03:35:41 pm
content: I sincerely appreciate your advice.My scope isn't worth much.I was trying to get it going for my nephew to fiddle with.I'm still searching for knobs closer to home.Again,I appreciate your help..

author: rf-messkopf
author_rank: Regular Contributor
timestamp: June 23, 2021, 10:44:16 am
content: Quote from: just me on June 22, 2021, 03:35:41 pmOkay, great. If you don't find any, shoot me a mail (address is on my homepage) and I'll check if the knobs on my parts mule are still okay.

author: just me
author_rank: Contributor
timestamp: June 23, 2021, 05:55:27 pm
content: Thanks..
Tektronix RSA3408A "UniqueID is empty" after HDD replacement - Page 1
Forum section: electronics / testgear

author: eb4fbz
author_rank: Regular Contributor
timestamp: June 21, 2021, 10:08:22 am
content: After suffering a couple of costly HDD failures in lab equipment, i dediced to replace the 40GB PATA HDD on my RSA3408A spectrum analyzer with a Trascend 64GB PATA SSD. Cloned the full HDD using Linux dd as usual.In the process, i found 7 bulged 1500uF 6.3V caps on the CPU board too, and replaced them too.The analyzer boots as usual, but the Tek RSA GUI complains "Option Key: UniqueID is empty" and refuses to respond to any key press. I'm afraid the licensing system uses the HDD ID, so with the new hard disk it fails authenticating the unit.Anyone has information about this analyzer platform? It seems an obvious preventive repair to me, given this analyzer is 15 years old.

author: eb4fbz
author_rank: Regular Contributor
timestamp: June 21, 2021, 11:20:22 am
content: I fixed it! Just needed to change Disk ID using Linux fdisk to match the original disk ID
CDEK SDS1202X 1Gs/s 200MHz scope - Page 1
Forum section: electronics / testgear

author: tttonyyy
author_rank: Regular Contributor
timestamp: June 21, 2021, 09:46:46 am
content: This was in my AliExpress recommended:https://www.aliexpress.com/item/1005001373939471.htmlWhat the flip-flop is that, aside from a bad CAD rendering? (A Siglent it most certainly isn't!)

author: rf-loop
author_rank: Super Contributor
timestamp: June 21, 2021, 10:20:37 am
content: It is (without real proofment IRL) rebranded Owon SDS1202, very low level scope but not so bad than some utterly useless fnirsi toys.
Tektronix blue filter - Page 1
Forum section: electronics / testgear

author: harrison@cs.unc.edu
author_rank: Contributor
timestamp: June 13, 2021, 08:54:56 pm
content: Some of this may be helpful to others that own Tektronix 'scopes.I wanted to replace the smoked filter on my 7603, but could not find one for a reasonable cost.Lowes has a small piece of 0.080 transparent plastic for less than 4 dollars. I bought a piece and cut it with a jig saw to match the size of thesmoked filter. I then glued a piece of GamColor theater gel to the back side of the plastic to make the filter. It seems to work well. It isn't thesame as the one from Tektronix, but it is the same color and was inexpensive.So...plastic piece $ 3.78GamColor #790, $9.95 ( 20 x 30 sheet )Hope this helps someone.

author: ps
author_rank: Regular Contributor
timestamp: June 19, 2021, 12:25:04 pm
content: In case someone needs an even more economic solution, cut the screen from the cover of a CD jewelcase.

author: David Hess
author_rank: Super Contributor
timestamp: June 21, 2021, 01:33:54 am
content: Art supply stores have transparent colored plastic film which may be the right shade of blue.Be careful about replacing the colored plastic filter if a clear one is not also installed because it serves as an explosion shield if the CRT should shatter.
Recommendation for purchasing DER EE DE-5000 LCR Мeter from eBay - Page 1
Forum section: electronics / testgear

author: Robin_55
author_rank: Newbie
timestamp: June 06, 2021, 11:45:23 am
content: Hi guys,I plan to buy DER EE DE-5000 from eBay. I have already read some discussions about unreliable sellers or fake products.Has anyone recently ordered this device from eBay? I need a recommendation for a reliable seller.

author: coromonadalix
author_rank: Super Contributor
timestamp: June 06, 2021, 11:48:17 am
content: I usually seek and buy from seller(s) who doesn't have negative feedback in 6 months or less .... yeah hard task to do but ...

author: nightfire
author_rank: Frequent Contributor
timestamp: June 19, 2021, 02:00:16 pm
content: German customer here: Ordered mine in February from tool.japan - Worked well. Of course, customs formalities in germany can get quite annoying, but thats normal.

author: Gregg
author_rank: Super Contributor
timestamp: June 19, 2021, 05:39:00 pm
content: Several years ago, I also purchased my DE-5000 with the accessory plug ins from tool.japan via ebay and am totally satisfied. The accessory plugs are stupid expensive if you buy them separately.

author: Analog4
author_rank: Contributor
timestamp: June 20, 2021, 07:17:22 am
content: available from Amazon:https://www.amazon.com/5000-Accuracy-Handheld-Meter-Tl-21/dp/B00O5537V0But this ebay seller, tool.japanhttps://www.ebay.com/usr/tool.japan?_trksid=p2047675.l2559,may be a good choice:https://www.ebay.com/itm/224073370894
Brymen 869s colour distroted display? - Page 1
Forum section: electronics / testgear

author: kgavionics
author_rank: Regular Contributor
timestamp: June 20, 2021, 02:57:48 pm
content: HelloI bought a Brymen 869s,it has been lightly used. Today, I noticed that the LCD has some coloured distorted spots. Is it normal, or it's a sign of failure?

author: Specmaster
author_rank: Super Contributor
timestamp: June 20, 2021, 03:21:13 pm
content: I have its sister, the 867s and the display is OK. I'm not sure what you are referring, the display is not a colour one at all. Are perhaps wearing glasses which are polarized? I know that if look at some displays wearing such glasses you can sometimes see where the plastic was stressed in the moulding process which looks like a mass of colours in some spots.

author: Fungus
author_rank: Super Contributor
timestamp: June 20, 2021, 04:03:16 pm
content: Photo??

author: kgavionics
author_rank: Regular Contributor
timestamp: June 20, 2021, 05:47:31 pm
content: It's hard to see it in the picture, but it's like a rainbow colours patches

author: Specmaster
author_rank: Super Contributor
timestamp: June 20, 2021, 07:43:06 pm
content: I see what you mean, but, because the screen is slightly convex, are you sure that this is not a reflection

author: Doctorandus_P
author_rank: Super Contributor
timestamp: June 20, 2021, 10:10:03 pm
content: LCD's can sometimes show colors when they are under mechanical stress. The effect is a bit similar to tiny amounts of oil floating on water.
Hameg HM408 calibration methods - question - Page 1
Forum section: electronics / testgear

author: sordid_resistor
author_rank: Newbie
timestamp: June 19, 2021, 04:35:21 pm
content: Hello all - I have a Hameg HM408 that my kind neighbour gave me, we're both are pro electroincs engineers and he had to leave planet earth (RIP).I've used it for general fault finding and it all seemes to work fine. However I come to do some measurements and notice it's out of cal. I feed it an accurate 1kHz and it's off, and so on for most of the ranges. Looking at the circuit diagram it seems this scope is hybrid where the Rs used in the X timebase are switched in like a binary counter from the digital part. This means each "bit" has it's own weighting and therefore each bit needs to be calibrated! (hand select resistors) Is this correct? Is this how Hameg expects us to calibrate the thing?I have set the X-Timbase Cal preset using 1kHz test signal and that is now correct but changing X-timebase still makes all other readings wrong and I can't find any other way than to hand select resitors for each of the "bits". Bit of a faff.I also notice the on board calibration oscillator is off freq, it looks just to be a simple CMOS gate osc so changing the Rs is easy enough.I have the circuits/manual, given them a good looking over and there's no clear instruction on how to calibrate the X-timebase.

author: tautech
author_rank: Super Contributor
timestamp: June 20, 2021, 12:04:34 am
content: As with any older instrument you should first be checking its PSU meets service manual specsexactly.So many old bits of kit fall back closer to spec when the PSU is reworked and adjusted to spec however scope componentry does age so in the absence of trimmers somewhere they can be difficult to align correctly.I'd be surprised if Hameg made no provision for accurate alignment however for the probe compensation output no provision for adjustment is not uncommon as what only matters is a fast edge and flat top so its absolute values only matter as a sanity check not a precision output.
Tek  TBS1000B  at 40% off ?? - Page 1
Forum section: electronics / testgear

author: Andrew_Debbie
author_rank: Frequent Contributor
timestamp: June 19, 2021, 03:46:27 pm
content: Any reason to consider a TBS1000 series scope at 40% off? MSRP is absurd but 40% off

author: rvalente
author_rank: Frequent Contributor
timestamp: June 19, 2021, 05:45:44 pm
content: Id never buy a scope with 2.5k points of memory when you can get much more with other brands

author: bdunham7
author_rank: Super Contributor
timestamp: June 19, 2021, 07:06:04 pm
content: If the TBS1052C were 40% off, that would be $306, which would make it a very cheap DSO, complete with Tek warranty and decent quality. That might make sense to someone outfitting an Electronics 101 lab or some other application where only very basic performance is needed, but commercial quality is wanted. And yes, the specs are miserable, but it is a perfectly functional device. I have a different Tek DSO with 2.5k memory and an antiquated feature set that is probably similar to the TBS1000 series, but it will still work 80% of the time for of what I need in the repair field.However, the bang-for-buck hobbyist or economy-minded professional would not be interested in such an outdated relic. Anyone that has used a more modern DSO will be quite disappointed in these.
Tektronix P6006 Probe cable type? - Page 1
Forum section: electronics / testgear

author: Crambone
author_rank: Frequent Contributor
timestamp: June 24, 2021, 08:42:10 pm
content: I was given a P6006 Probe assembly but the coax is cut and I would like to try to repair but can’t tell what cable/ coax it uses?

author: bdunham7
author_rank: Super Contributor
timestamp: June 24, 2021, 08:51:23 pm
content: https://www.ebay.com/itm/233342197223
DSOX4000 corrupted flash - Page 1
Forum section: electronics / testgear

author: oaba
author_rank: Contributor
timestamp: June 18, 2021, 10:51:26 pm
content: My scope DSOX4025 was stoping at the ref button. Does not boot.I was connecting to the scope by serial.And:XXXXXXOOOOXXOOOOOOOOXOXXOOOOOOOIncorrect Data 1 EccResult: 3c3330 EccError: c0c03c EccRead: fcf30cEBOOT_ReadFlash failed offset 4ad764EBOOT_ReadFlash failed location d04b4000ODeCompressFlash: CeCompressDecode() failedCeDecompressFlashBlock failed****** Data record 11 corrupted, ABORT!!! ******I would need the 2.35 firmware because that is the only one boots from USB.If any one can share tha link please?

author: oaba
author_rank: Contributor
timestamp: June 19, 2021, 07:36:27 am
content: I was just reading no such a firmware exist. 3.0 was the earliestIf you know how to fix it if you could help me to point to the right direction please?

author: tv84
author_rank: Super Contributor
timestamp: June 19, 2021, 08:35:28 am
content: Readthisthread.
Cheap card style osciliscope? - Page 1
Forum section: electronics / testgear

author: unknown_h
author_rank: Contributor
timestamp: June 18, 2021, 01:29:55 pm
content: I feel like I am chasing something that doesn't exists, and my ability to google has failed me so I am turning to the collective brain trust on here. Is anyone aware of any lower cost PXI, PCI or or other modular test equipment form factor oscilloscope? I am not looking for something with amazing abilities and I am aware that USB oscilloscope exist( mostly without proper grounding) I just don't want to have to deal with tones of usb cables and would prefer to have have a single chassis for all my test equipment with a single interface for my computer.

author: wn1fju
author_rank: Frequent Contributor
timestamp: June 18, 2021, 08:48:38 pm
content: I haven't seen too many PCI-E oscilloscopes that I would call "cheap." Over the years at my job, I've bought ones from Gage, National Instruments, Acqiris and AlazarTech. All of them were several thousand dollars plus.On the other hand, with an embedded scope card in a computer, you have to worry about 1) isolation (so you don't blow up your computer), 2) noise/interference from the PC itself, 3) lower quality power supply in the PC feeding the scope, etc. I'm sure the good scope cards take care of these issues and that's why the prices are a bit high for the casual user.You might expand your search to include PCI/PXI digitizer cards. Most of them come with a demo-like scope application. Obviously, the cost of the digitizer is a function of number of channels, sample rate, number of bits, max bandwidth, etc.

author: james_s
author_rank: Super Contributor
timestamp: June 18, 2021, 09:20:01 pm
content: I think pretty much all this sort of stuff has gone USB, and IMO it makes sense. If you want a PC based scope, just use USB, it's only one cable. If you want an all-in-one box, buy a standalone oscilloscope, a lot of higher end ones are PCs inside anyway.
UNI-T UT204+ Microcontroller info - Page 1
Forum section: electronics / testgear

author: Techmidi
author_rank: Newbie
timestamp: September 13, 2019, 06:22:24 pm
content: Today I received the UNI-T UT 204+ clamp meter, I think it is very new in the market I have not found info,I am trying to extend the amperage range low to 2A I have opened the clamp and from what i see it has a dataport it seems usb, I have connected it to the pc but it gives connection error I leave the samples of the logicanalyzer, to continue the investigation I need to know which It is the used microcontroller, I thought of theFortune FS9721 but pins do not match, if someone could tell me what microcontroller it carries would be greatregards

author: 001
author_rank: Super Contributor
timestamp: September 14, 2019, 03:50:01 pm
content: Nowday top meters of UNI-T usually based on DTM0660/DM1106/ES222 meter chip + Cortex microprocessor

author: Techmidi
author_rank: Newbie
timestamp: September 14, 2019, 06:54:11 pm
content: Pin-out is very similar to Fortune FS9952 but not the same also does not match features count 2000 vs 6000 ...it could take otp memoryI'm still investigating,thank you for your support

author: Kashif khan
author_rank: Contributor
timestamp: April 10, 2021, 10:27:25 am
content: hello,read your post for uni-t 204+ about the chip used inside the multimeter unfortunately its is COBed...well i have uni-t 203+ and i too wanted to reverse engineer the multimeter because i strongly believe the 204+ and 203+ have same hardware just change programing....i managed to find the chip used inside the multimeter its was "SD7501" datasheet attached, but here the story ends because the chip was OTP and there was no EEPROM chip.if you could find something interesting ...let us know.~regards

author: abidjbit
author_rank: Newbie
timestamp: June 18, 2021, 01:00:44 am
content: My device ut204+ using Sd7501.
121GW Multimeter - Simon says - Page 1
Forum section: electronics / testgear

author: PerranOak
author_rank: Frequent Contributor
timestamp: June 17, 2021, 04:01:17 pm
content: I notice that the 121GW Multimeter is for sale in the UK from "Simon's Electronics".Do we know/trust this supplier?Cheers.

author: tunk
author_rank: Super Contributor
timestamp: June 17, 2021, 04:21:39 pm
content: I think he's one of the moderators here.Click on his signature here:https://www.eevblog.com/forum/profile/?u=58

author: Fungus
author_rank: Super Contributor
timestamp: June 17, 2021, 08:09:17 pm
content: Quote from: PerranOak on June 17, 2021, 04:01:17 pmYes, definitely. He's here on EEVBLOG.

author: PerranOak
author_rank: Frequent Contributor
timestamp: June 18, 2021, 06:13:41 am
content: Excellent, he’s one of us!Hi Simon.

author: tautech
author_rank: Super Contributor
timestamp: June 18, 2021, 07:40:52 am
content: Quote from: PerranOak on June 18, 2021, 06:13:41 amAmazing you've been here since early 2016 and you didn't know Simon our longest serving moderator and that he has sold Dave's products in the UK for many years.Any of us that have a blue globe in our profile are also very likely to have a website selling our own or some manufacturers product.

author: PerranOak
author_rank: Frequent Contributor
timestamp: June 18, 2021, 10:40:49 am
content: My shame is complete.

author: tv84
author_rank: Super Contributor
timestamp: June 18, 2021, 10:48:00 am
content: Quote from: PerranOak on June 18, 2021, 10:40:49 amYou are forgiven. Nonetheless it's easier to find here tautech than Simon, even in a different timezone...

author: 2N3055
author_rank: Super Contributor
timestamp: June 18, 2021, 11:33:42 am
content: Quote from: tv84 on June 18, 2021, 10:48:00 am
HP 8664A Performance - Page 1
Forum section: electronics / testgear

author: Ground_Loop
author_rank: Frequent Contributor
timestamp: June 17, 2021, 01:13:14 am
content: I was goofing with my HP 8664A sig gen today and noticed a number of harmonics I don't recall being there. Please see attached. Is it normal for the first harmonic to be only roughly 43 dB down from the fundamental? Frequency output is 100MHz @ 0dBm. Center frequency is shifted a bit on the SA to get the trace off the grid line.

author: bdunham7
author_rank: Super Contributor
timestamp: June 17, 2021, 02:35:39 am
content: I don't think it would be normal. I had one of those here for service a while back and I took some pictures (at 100MHz no less) but it was all close-in spurs and modulation stuff, no wide-span analysis. I think the outputs were fairly clean and I'd be surprised to see harmonics that high. I just peeked at the manual and I can't find specs right now. What happens if you reduce the amplitude?

author: TimFox
author_rank: Super Contributor
timestamp: June 17, 2021, 03:09:46 am
content: I found a specification sheet. Depending on the exact model and level, harmonic content is specified as -25 dBc or -30 dBc. Other spurs are far lower.

author: bdunham7
author_rank: Super Contributor
timestamp: June 17, 2021, 03:51:42 am
content: OK, some stuff just trickled back into my brain--and I found some photos that I took of it in action (it went on eBay). The manuals are not well organized for figuring this stuff out. Maybe it's not broken after all.There are controls for 'synthesis mode' on the lower right. Only two of them work unless you have the option for enhanced spectral purity (don't remember the number). I don't know how much, if any, effect this will have on harmonics.Do you have Option 002 (Frequency doubler)? I think the harmonics are worse with that option.I think the harmonics will be higher at higher drive levels. Drop down 5dB at a time and see what the harmonics do.I still haven't found the spec sheet thatTimFoxmentioned, but -25dBc at 100MHz seems high, but maybe it doesn't matter for its intended uses.EDIT: Here it is, in black and white. Guaranteed specs for harmonics are only <30dBc @ <10dBm.https://www.testequipmentdepot.com/usedequipment/pdf/8644b-8664a-8665b.pdf

author: Ground_Loop
author_rank: Frequent Contributor
timestamp: June 17, 2021, 11:38:43 am
content: I located the spec sheet as well. Seems to be in spec. Nonetheless, after appropriate warm up, I performed an internal recalibration and instrument test. Returned result code zero for both. The center frequency and amplitude tightened up a bit, but harmonics were unchanged. This is one of the nicer instruments I own and would hate to think it's going South on me. Thanks for the replies.

author: TimFox
author_rank: Super Contributor
timestamp: June 17, 2021, 01:39:41 pm
content: Harmonics: -40 dBc is 1% harmonic distortion, in other terms. This is not atypical for signal generators, since the output stage is not tuned.
IPS-405 Programable Power Supply, RS232 Interface - Page 1
Forum section: electronics / testgear

author: dmg0345
author_rank: Newbie
timestamp: June 16, 2021, 04:15:53 pm
content: Hi everyone,The IPS-405 and related are quite popular power supplies and I was hoping someone could help me find a cable to properly connect to this power supply through the RS232 interface from a USB port in my computer.I have an ISOTECH IPS-405 Power Supply like this one:https://www.enrgtech.co.uk/buy/product/ET13984959/IPS-405.I am familiar with serial ports, UARTs, COM ports and the like however I am struggling to find a RS232 to USB for this PSU, from the manual:And this is the connector on the back of the PSU:I find it quite atypical and non standard, this is neither a straight through cable nor a null modem cable, and I am confused as to why I need 12V on that pin, and not anything between 5V and 15V as defined in the RS232 spec for a high level, I have read that some old devices only worked with 12V and rejected any other voltage, I suspect the RXD and TXD pins might work with this voltage too.Has anyone with a similar PSU recommend any RS232 to USB cable for this board? It does look like I need a custom one, but I hardly believe that this was the expected use case by the manufacturers of this PSU, I am probably missing something.Thank you for your time.

author: bingo600
author_rank: Super Contributor
timestamp: June 16, 2021, 06:13:11 pm
content: Guess about the 12v.It powers an opto isolation thingy in the PSU , so your computer & psu are isolated from each other./Bingo

author: dmg0345
author_rank: Newbie
timestamp: June 16, 2021, 07:23:00 pm
content: Quote from: bingo600 on June 16, 2021, 06:13:11 pmYou are probably right, I came across what seems to be the schematics of this PSU (or a very similar model) and noticed the following:I thought the 12V signal was DCD, but looking at the schematics it does not look like that, it does something with the optocouples there.So I guess this provides some clarity, but I still wonder what kind of wire where the original manufacturers expected people to use because I can't find any and I would rather avoid doing something custom.EDIT: Forum seems to be resizing the image, the image can be seen here:https://ibb.co/NxJ1xpt

author: dmg0345
author_rank: Newbie
timestamp: June 16, 2021, 08:16:58 pm
content: I also looked at the datasheet of the Winbond UC with the TXD/RXD signals, and noticed that the ranges of Input/Output for the TXD and RXD signals are in the range of 0V to 5V it seems:https://ibb.co/n3Ybpfq.So it looks like a 12V input, a normal UART and a RS232 connector.
Brymen BM869s DC min crest - Page 1
Forum section: electronics / testgear

author: oxoocoffee
author_rank: Newbie
timestamp: June 14, 2021, 03:56:56 pm
content: Hello,I got my new 968s unit and last Friday to wanted to take measurement on my Nvidia Nano 40 pin 5V to ground.Setup:So I have camera that is about 65Feet away from my Nano. This camera is connected using usb-over-ehternet. So I need to provide 5V external power to module on opposite side or nano to provide external power. So along the the Ethernet cable I have 18awg cable connected to 40 pin on nano to supply 5V. I am considering also switching to 12 V and use buck converter at the other end to connect to 5 V. Please note this is temporary solution since I am considering CAN FD or PoE for remote thermal camera.Issue:Then I connect my 869S to measure voltage on 5V pin to ground I select DC and crest min to log minimum voltage over time. The issue I am seeking that such voltage drops to around 5.06V (where no load placed on such 5V pins, voltage is around 5.2V). After several hours ~15 or more I see -4.65V on my multimeter. Not sure how to explain this. Is this some problem with multimeter running for a long time? Does any one noticed this?Or is there some other explanation.Thank you for all comments

author: radiolistener
author_rank: Super Contributor
timestamp: June 14, 2021, 04:49:12 pm
content: it's just random interference on wires which you're using to attach DMM to the circuit.BM869/BM867 has wide bandwidth in CREST mode. Just tested, it's 3 dB bandwidth is about 1055 Hz. So it very sensitive to a noise and pulse interference. Your wires just works like antenna and receiving electromagnetic pulses from other equipment in your environment. This affects the measurements results. Also it may be just a noise of DMM ADC.When you use usual DC measurement mode, the DMM filters all these pulses and show you average value. But when you use CREST mode, you will see all noises.

author: oxoocoffee
author_rank: Newbie
timestamp: June 15, 2021, 08:33:34 pm
content: Thank you for your help and explanation.I think a better option for what I wanted to accomplish is pressed REC mode in DC and check Min/Max to read RMS peaks.I did read multimeter documentation and I am a bit puzzled when you use Crest min/max vs Rec min/max?Could some one explain each case and when to use each?On another hand, what I did experienced in Crest mode is still strange to me that polarity was almost reversed just by induction? That much? I like to lear more about that.
Megger BM80/2 repair or adjustment? - Page 1
Forum section: electronics / testgear

author: Oldtestgear
author_rank: Regular Contributor
timestamp: May 30, 2021, 09:37:02 am
content: I have a slightly tatty Megger BM80/2 ( ex Royal Navy so may have been swimming from the corrosion) that works on most ranges except the KOhm range which has an offset of ~1KOhm. Does anyone have a manual or adjustment procedure that they would share? Any help appreciated as I would like to get this thing working again.ThanksPhil

author: I4E
author_rank: Regular Contributor
timestamp: June 03, 2021, 01:46:42 am
content: Checking to see if we have a copy of the manualThanksJoy TorresInstruments 4 Engineers ltdwww.instruments4engineers.com

author: Oldtestgear
author_rank: Regular Contributor
timestamp: June 03, 2021, 04:30:20 pm
content: Thanks for looking.Phil

author: I4E
author_rank: Regular Contributor
timestamp: June 04, 2021, 11:48:14 pm
content: I've got a copy of the user manual. Would this be of interest?Miss Joy TorresInstruments 4 Engineers ltdwww.instruments4engineers.com

author: Oldtestgear
author_rank: Regular Contributor
timestamp: June 06, 2021, 10:49:45 am
content: Thank you for the offer of a user manual. Unfortunately this does not include any information on recalibrating the meter. I am still hoping that someone will have enough information (even a schematic) so that I can get the thing working to spec. again.Phil

author: I4E
author_rank: Regular Contributor
timestamp: June 15, 2021, 01:39:20 am
content: Thank you. Sorry. I don't have that. If I can get a hold of it then happy to give it to youJoy TorresInstruments 4 Engineers ltd
Siglent SDL-1020X-E 'white screen' problem - Page 1
Forum section: electronics / testgear

author: danjayh
author_rank: Newbie
timestamp: June 14, 2021, 05:19:28 pm
content: Hello, just wondering if anyone else here has experience with the siglent SDL 1020 X-E DC load. I just purchased one, and half the time when turn it on that just shows a white screen and doesn't boot. when it does boot it works fine. It's running the latest firmware, so I'm thinking it must be a hardware problem. Right now I'm planning to send it back, but it's a pain since I got it through our corporate procurement procedure.Has anyone else purchased one of these and had similar problems? I'm hoping for a solution that doesn't involve returning it, but I understand that that's not likely. Thanks for your input!

author: tautech
author_rank: Super Contributor
timestamp: June 14, 2021, 07:49:14 pm
content: Welcome to the forum.Oh dear, we had one unit in NZ that had this problem and it turned out to be a display connection issue and parts were needed.Contact Siglent Ohio and let them fix or replace it.https://siglentna.com/contact-us/
HOPI HP-9800 Software - Page 1
Forum section: electronics / testgear

author: aargee
author_rank: Frequent Contributor
timestamp: January 22, 2021, 09:45:55 pm
content: Hello all,After a fruitless search, I was wondering if anyone has, or knows of, logging software for the HOPI HP-9800 power meter?They splash an image on the box, which seems to be just a mock up.TIA- Rob

author: davipoyastro
author_rank: Newbie
timestamp: June 14, 2021, 12:55:03 pm
content: There are two projects in github, one in C and another in python.I tested the python version (raplin/Hopi_HP-9800_Python_simple.py) and had to convert the print functions to pyhton3 but it worked.Don't expect much from that, is just a dump from the screen like this:Active Power 9.599WRMS Current 0.070AVoltage RMS 234.200VFrequency 50.045HzPower Factor 0.582pfAnnual Power 84.090KWHActive Power 0.003KWHReactive Power 0.005KWHLoad Time 20.689mins

author: HKJ
author_rank: Super Contributor
timestamp: June 14, 2021, 01:22:38 pm
content: Depending on the protocol, it may be easy to add it to TestController. That would give it logging and graphing capabilities.
Transplanting a tracking generator option into another 8591C - Page 1
Forum section: electronics / testgear

author: Kitski
author_rank: Newbie
timestamp: June 13, 2021, 03:58:52 am
content: Hi Team,I have a non-working 8591C with option 011 (Tracking generator) installed and am considering removing this assy (as shown in the Service Guide, p469, Fig 11-18) and inserting into another working 8591C.While it looks like a nightmare to physically remove and replace, would the donor's 8591C firmware recognise the new module, show on the user-menu and actually do it's TG magic ?Any suggestions and hints warmly welcome !Thanks in advance,Kitski

author: bob91343
author_rank: Super Contributor
timestamp: June 13, 2021, 05:15:37 am
content: I would love something like that for my 8594L.

author: Kitski
author_rank: Newbie
timestamp: June 13, 2021, 05:35:51 am
content: Hi Bob91343,Are you seeking a complete replacement option 011 assembly to replace an existing faulty assy or to retro-fit the option like I'm attempting to do ?I'd rather hear from someone who has successfully removed this 011 assy before attempting it myself as any securing screws are (very) well hidden and the service manual offers few, if any clues.If the assy can be transplanted and the firmware recognises the option, it may be a worthwhile exercise. Otherwise ....Kitksi

author: ps
author_rank: Regular Contributor
timestamp: June 19, 2021, 12:22:17 pm
content: Quote from: Kitski on June 13, 2021, 03:58:52 amWith a HP 8591A this worked without any issues. There are two calibration constants that need to be entered after the TG has been fitted. Usually they are written onto the module, otherwise you will have to extract them from the donor system before scrapping.
Affordable CAT6a certifier? - Page 1
Forum section: electronics / testgear

author: oh2ftu
author_rank: Regular Contributor
timestamp: June 12, 2021, 05:48:54 pm
content: This will most probably just be me blabbing a huge mess, but I'll let 'er rip anyway.I've been doing my own CAT6a cabling runs at my home and some other places. Also, some fiber splices or readymade fibers.I'd like to verify them to a wider extent than a basic pair-tester.There's been a few auctions with either a Viavi/JDSU 40G certifier or a Fluke DTX-1800. But those all went way above my measly budget.Mostly I need cat6a testing, but verifying single- and multimode (both 62,5 and 50) would be nice - even just at a power meter level.Getting a power meter and light source from fs.com would set one back ~200 EUR, which ain't that bad for testing basic fiber connectivity. Including a VFL (I already have one) makes for a nice setup.What's your take? I would rather spend under USD1000 including shipping, but that seems to be not possible.What's on ebay is mostly Wirescope 350's, but these have been EOL for a LOONG time. Fluke's DTX-1800's go for 2-4k USD, but even these are EOL'd for some time now.Is rental the only option?

author: David Hess
author_rank: Super Contributor
timestamp: June 12, 2021, 07:11:00 pm
content: If I wanted the cheapest possible ghetto solution for 10GBASE-T testing of CAT6a cable, I would get a pair of 10GBASE-T interfaces, which might even be ports on the same switch, and connect them to the cable to be tested along with an extra length of CAT6A cable (25 to 50 meters?) spliced in using a female-female adapter. The extra length of cable provides the testing margin.

author: fordem
author_rank: Regular Contributor
timestamp: June 13, 2021, 01:33:41 am
content: Quote from: David Hess on June 12, 2021, 07:11:00 pmA number of years back the firm I was working with invested in a Fluke DSX - and just for the heck of it I ran a couple tests on a few short lengths of CAT5e cable, and I did one with two cables joined by an female-female adapter, whilst I no longer have the print out I can tell you that even at gigabit standards, the female-female adapters are crap - use them only if you have no other option and I'd rather grab a couple of keystone jacks and a few feet of cable and punch down my own female - female adapter, I can guarantee lower cross talk.
Atorch DL24 (from Amazon) win! - Page 1
Forum section: electronics / testgear

author: xenoxaos
author_rank: Contributor
timestamp: June 10, 2021, 05:07:28 am
content: So, I was impatient and instead of ordering from aliexpress etc, I ordered mine on Amazon. Figured if I didn't like it or it was a complete POS, I could easily return it. Came next day and everything was fine. I noticed some of the plastic on the edge of the MOSFET had chipped off. So I contacted the seller and they were like "yeah that can happen sometimes when smushing it down, let me send you another one." I didn't have to return it. 1st win. About an hour later they email me back saying that the Amazon distribution center had one that they received damaged and asked if I would like it instead of it going to landfill. Of course I said yes. I figured I'd be able to at least salvage something off of it... Heatsink, fan, display, something.Today the "broken" one arrived and I unpacked it and plugged it in. Everything appeared to be working. Hmmmm...But OK. I then noticed in the bag of cables that ONE of the alligator clips has the pin popped out.TLDR; Because I'm impatient, I got 3x DL24 for the cost of one overpriced one.

author: Brumby
author_rank: Unknown
timestamp: June 10, 2021, 07:52:33 am
content: Now you know why they are overpriced.

author: thm_w
author_rank: Super Contributor
timestamp: June 10, 2021, 10:07:22 pm
content: That is cool that they were able to send you the damaged unit.Amazon returns are a complete money/resource pit.

author: james_s
author_rank: Super Contributor
timestamp: June 11, 2021, 05:01:18 am
content: I remember seeing a video a while back where someone bought a big box of Amazon returns. As I recall it seems like it was mostly just a bunch of junk I wouldn't want for free and I don't think it was particularly cheap. Sure didn't strike me as a bargain.
What probes for a 400mHz HP54504A with 7pF input capacity? - Page 1
Forum section: electronics / testgear

author: Peter_O
author_rank: Frequent Contributor
timestamp: June 09, 2021, 11:54:25 am
content: I could not resist to rescue a 400Mhz HP54504A digital oscilloscope in best shape for 160 Euros.It comes without probes.I'd like to have dedicated probes for this one. I do not need to use the highest freqencies and probe budget should be in some kind of relation to the sum above.Input capacity is 7pf acc. to datasheet:www.testequipmenthq.com/datasheets/Keysight-54504A-Datasheet.pdfThe compensation range of many budget probes like testec 312 HF seems to start at 10pF.Does anybody has a recommendation of good budget probes?
Philips PE1002 - isolation transformation question - Page 1
Forum section: electronics / testgear

author: chj9183
author_rank: Newbie
timestamp: June 08, 2021, 08:21:07 am
content: Hi all,does any know what this isolation does exactly, apart from isolating of course?https://www.2ememain.be/a/hobby-loisirs-creatifs/composants-electroniques/m1496254926-alimentation-philips-pe-1002-et-transformateur-d-isolement.html?c=9b26ed2a557deff636f4f8b9c5b7a618it is also a variac?does any have any info on this?ThanksRobin

author: rdebets
author_rank: Newbie
timestamp: June 09, 2021, 09:34:44 am
content: It is a line voltage stabilizer. The output voltage can be stabilized based on average, effective or peak value.Here is an add with details in Dutch, page 15a:https://nvhrbiblio.nl/biblio/tijdschrift/Radio%20Electronica/1969/Radio%20Electronica%201969-22-OCR.pdfThe add says it is transistorized, pretty good for that era and power rating
Agilent Probe Parts - Page 1
Forum section: electronics / testgear

author: Wallace Gasiewicz
author_rank: Super Contributor
timestamp: June 06, 2021, 09:12:48 pm
content: Are there any acceptable substitutes for Agilent 1160 mini probe parts like a grabber or hook tip?Wally

author: Someone
author_rank: Super Contributor
timestamp: June 07, 2021, 05:39:04 am
content: Other 2.5mm accessories tend to work ok, Lecroy PP007 etc.
HP 34401A screen display connector - Page 1
Forum section: electronics / testgear

author: dorkshoei
author_rank: Frequent Contributor
timestamp: January 12, 2021, 07:41:52 pm
content: 1. What is the trick to removing this connector? I thought you pressed backwards on it but mine isn't coming off and I don't want to break it.2. Does anyone know the part# for the connector. I'd like to make an extension cable so I can have the display pcb powered but relocated away from the unit (for debugging).

author: coromonadalix
author_rank: Super Contributor
timestamp: January 12, 2021, 09:57:37 pm
content: normally you press/ push it down toward the pcb to release the flat cable while "still pressed/pushed" sometimes the connectors pins seems stuck with the flat cable, while pushed try to gently very gently move it left to right, mine got unstuck and was working fine.normally the cable is long enough to do debugging

author: dorkshoei
author_rank: Frequent Contributor
timestamp: January 13, 2021, 12:03:08 am
content: Quote from: coromonadalix on January 12, 2021, 09:57:37 pmI would like to make an extension, so if anyone is able to answer the question asked I would appreciate the info. Thanks!

author: vtp
author_rank: Regular Contributor
timestamp: January 13, 2021, 12:48:53 pm
content: Quote from: dorkshoei on January 12, 2021, 07:41:52 pmOriginal is obsolete IIRC but I used Molex 52147-1210 to replace it in one of my instruments, its drop-in replacement. Seem to be NRND now so get yours while still available.

author: dorkshoei
author_rank: Frequent Contributor
timestamp: January 13, 2021, 04:31:46 pm
content: Quote from: vtp on January 13, 2021, 12:48:53 pmThank you.Digi-Key states the following. So yes, worth buying a couple just in case the one on your meter ever has an issue.Part Status: End of Life; Last Time Buy Date: 6/21/2021.

author: Keith956
author_rank: Regular Contributor
timestamp: June 10, 2021, 07:19:46 am
content: You don't have to replace the connector like with like. The Molex push-in-the-wire connectors are very prone to bad connections and bent or broken cable wires. I replaced mine with a 2mm PCB header and a socket with crimp pins on the cable. RS sell them (RS numbers 779-3106, 779-2901 and 172-1786).
Info wanted: National Instruments DAQCard-6062E - Page 1
Forum section: electronics / testgear

author: User32
author_rank: Contributor
timestamp: April 29, 2021, 03:06:06 pm
content: What is this CardBus device for? I bought a laptop for parts and it had this card in it's PCMCIA slot.

author: alm
author_rank: Super Contributor
timestamp: April 29, 2021, 05:20:38 pm
content: It's a data acquisition device which has a number of analog input and output channels, connecting to the likely missing dongle that plugs into the side of the card. Kind of like having multiple multimeters, except that they only have a single voltage range. You could use it to measure sensors and control actuators, for example.Here you see a number of modern devices that do something similar but using more modern I/O like USB:https://www.ni.com/nl-nl/shop/data-acquisition.html

author: IRFP
author_rank: Contributor
timestamp: April 29, 2021, 05:36:14 pm
content: Good evening,It is a DAQ, there are PCMCIA - USB converters to recycle the card.

author: User32
author_rank: Contributor
timestamp: April 29, 2021, 06:27:09 pm
content: Quote from: alm on April 29, 2021, 05:20:38 pmInteresting. Any particular reason that they're asking ridiculous prices for it on eBay?

author: alm
author_rank: Super Contributor
timestamp: April 29, 2021, 08:07:23 pm
content: Are they actually selling for those prices, or is it just people hoping that some day someone desperate will come that will pay a ridiculous price? The only reason I can see is to replace a card that is in some existing setup that has to meet some stringent certification, and changing the procedure is more expensive than buying a new card. Like if it was part of an Airforce procedure to maintain an F-16. Otherwise I'd say the thing is almost useless without its dongle.

author: User32
author_rank: Contributor
timestamp: April 29, 2021, 08:41:41 pm
content: Quote from: alm on April 29, 2021, 08:07:23 pmA similar card (6036E) sold for $90 last February:https://www.ebay.com/itm/284122762891I had some tard offer me €5 lol

author: User32
author_rank: Contributor
timestamp: June 05, 2021, 01:42:59 pm
content: I had zero offers for it so I guess there's no market for these anymore. Time to toss it?

author: rvalente
author_rank: Frequent Contributor
timestamp: June 05, 2021, 06:21:02 pm
content: I'd use it, I'm not sure if you're familiar with labview but, you can do a lot of interesting things with the "virtual instruments", I was looking for DAQ board myself, its a shame there is no dongle but, you can always make a break-out board.anyway, its really useful