hybridfree/eevblog-posts huggingface dataset:
Old HP/Agilent power supply buttons - Page 1
Forum section: electronics / testgear

author: SharpEars
author_rank: Unknown
timestamp: December 04, 2016, 10:15:58 pm
content: Where do you guys get yours from. Many old supplies are being sold with damaged buttons and I would like to replace some broken buttons in mine, without having to buy an entire new front panel for hundreds of dollars or having to canibalize them from another supply. Where do I get replacement white buttons for digits, output on/off, etc. They don't have to be labeled, just the right shape to fit HP power supplies which all have these buttons of a standard size.I am talking about these guys and color is unimportant:These are the buttons I need to replace (OCP and OV, to be specific) (I don't care if they are blank white, gray, or whatever buttons as long as they will fit and work):

author: Macbeth
author_rank: Super Contributor
timestamp: December 04, 2016, 10:30:16 pm
content: They don't come as individual buttons but a complete front panel rubber assembly. Of course if you don't care for aesthetics then there is no reason you can't cut some from any spare flappy HP panel of the era and use them with a bit of tape?If it's purely function then you could even strip down a shitty TV remote control and use the graphite pads and rubber on the back of them - just mount something on top to prod them with.

author: djnz
author_rank: Regular Contributor
timestamp: December 05, 2016, 02:59:12 am
content: If the rubber sheet / graphite is not damaged, I've had some good luck using a properly cut piece of an eraser. If you cut it to be slightly bigger than the hole / frame it's supposed to fit in, if doesn't fall out easily either because of the increased friction. Very much a kludge, but it works. If the graphite is damaged, I suppose gluing a piece of foil to this eraser piece might do the trick.

author: SharpEars
author_rank: Unknown
timestamp: December 05, 2016, 12:59:52 pm
content: Bump... Still looking for a source for actual buttons, without having to buy an entire front assembly, cutting rubber to fit, or cannibalizing other supplies.

author: Macbeth
author_rank: Super Contributor
timestamp: December 05, 2016, 01:25:21 pm
content: Sorry, I got the impression you only wanted individual buttons and didn't care what colour or labels, etc. These aren't available as the keypad is a complete rubber sheet.I assumed you tried the obviousKeysight Find-A-Partand your keypad is obsolete?My HP 6632B keypad is available 06612-40001 for £21 GBP for example.

author: SharpEars
author_rank: Unknown
timestamp: December 05, 2016, 07:00:28 pm
content: Quote from: Macbeth on December 05, 2016, 01:25:21 pmI am looking for individual buttons. I didn't realize that the keypad is an entire sheet on the 665xA supplies - I thought that the buttons were individual.

author: Macbeth
author_rank: Super Contributor
timestamp: December 05, 2016, 08:42:35 pm
content: Quote from: SharpEars on December 05, 2016, 07:00:28 pmEven better, 5040-1735 is the entire keypad exactly what you want and is only £15 quid - and 3 in stock!
ATTEN LISN AT-166 opinion? - Page 1
Forum section: electronics / testgear

author: urgu
author_rank: Newbie
timestamp: November 11, 2015, 01:32:33 pm
content: Hi,Does anybody have experience with LISN pointed in topic?Is it actually usable or better to build own?I have previously used home-built ferrite clamp based conducted emission probe and also professional gear but never had experience with cheap device like that.Kind regards,Ergo

author: urgu
author_rank: Newbie
timestamp: November 15, 2015, 07:31:53 pm
content: This ATTEN device is much cheaper. This was main idea behind my question.Of course i am sure they know how to wind coils in China but do they actually care about EU/US standards...BR,Ergo

author: morzineIT
author_rank: Newbie
timestamp: December 05, 2016, 11:17:12 am
content: If you're still looking for one, I have a HM-6050 II for sale,I will be listing it shortly on the forum
Rigol DS1032Z - Counter - Low Frequencies - Page 1
Forum section: electronics / testgear

author: juliank
author_rank: Newbie
timestamp: December 19, 2016, 03:49:01 pm
content: Anyone tried to measure low frequencies on the counter of the Rigol DG1000Z Waveform generator series. I've been trying to measure below 1Hz and not having much luck.The counter seems like it needs a relatively long Gate Time to get reliable results on any frequency, so the 10s gate seems OK down to around 500mHz, lower than that and it's highly variable readings on a stable waveform. There is a >10s gate time setting, but I can't get that to produce any readings.Just curious if anyone has come across similar issues?My first post so go easy on me

author: grumpydoc
author_rank: Super Contributor
timestamp: December 19, 2016, 04:02:48 pm
content: You are probably better off setting it to measure period and converting.
Rigol DG4000 series: How to generate a degraded square-wave? - Page 1
Forum section: electronics / testgear

author: asilva10
author_rank: Contributor
timestamp: December 05, 2016, 12:17:59 am
content: I am in need of generating a distorted square wave with my Rigol DG4202:What software can I use?Thank you!!

author: Dubbie
author_rank: Unknown
timestamp: December 05, 2016, 10:30:27 am
content: Could use a sound card if you don't need a frequency too highSent from my phone using Tapatalk

author: Pinkus
author_rank: Frequent Contributor
timestamp: December 05, 2016, 11:01:06 am
content: This is also an arbitrary function generator, so you can just load any waveform you like.I remember that there is a free Rigol software called UltraWave, where you candrawthe waveforms you like to see generated.Edit: the above only applies to the DG1000 and DG3000 series.For the DG4000 I think it is called Ultrastation.......... OK did some search:There is a free version and an advanced version. Waveform editing and uploading is free. So just download and use:http://www.rigol-uk.co.uk/Rigol-Ultra-Station-Advanced-PC-Software-Licence-p/ultra-station-adv.htm#.WEVJOdXhD0M

author: H.O
author_rank: Frequent Contributor
timestamp: December 05, 2016, 11:13:52 am
content: And if you have a Rigol scope and a real live source for such a waveform you can capture and transfer the waveform directly from the scope to the generator for "play back".

author: TurboTom
author_rank: Super Contributor
timestamp: December 05, 2016, 11:33:09 am
content: If you add CH1 and Ch2 (either internally -- don't know if that's possible -- or externally by simply "T"-ing them together) and output a square wave on one channel and a triangular wave on the other and adjust the same frequency on both, it shouldn't be difficult to adjust phase and amplitude in relation to each other to generate any sloped square that you like. Of course, this would require both channels so if you need the second channel for something else, this isn't possible. I'm not sure if some modulation function may be configured to produce the same result.Cheers,Thomas

author: PA0PBZ
author_rank: Super Contributor
timestamp: December 05, 2016, 03:14:54 pm
content: Modulate the square wave in the DG4000 with an upramp, then play with the square wave phase to get it in the correct position:
KEITHLEY 2000 MULTIMETER  OVERFLOW with no input - Page 1
Forum section: electronics / testgear

author: Jester
author_rank: Frequent Contributor
timestamp: December 05, 2016, 12:14:31 am
content: I noticed this Keithley 2000 on ebay:http://www.ebay.com/itm/KEITHLEY-2000-MULTIMETER-/252659406882?hash=item3ad3ac9822:g:0oAAAOSwa~BYPaXmSeller claims it works, but I see no reason the display would indicate overload with no input, then again I have never used one of these. What do you think?

author: mimmus78
author_rank: Unknown
timestamp: December 05, 2016, 12:41:53 am
content: This meters have a very high input impedance so they typically build up some charge if they are not connected or shorted ... despite this I never seen those meters to go in overload especially if autorange is enable (and in this case it's enable).

author: TheSteve
author_rank: Unknown
timestamp: December 05, 2016, 03:38:30 am
content: There is bright light to take the photo but even taking that into account that is an awful dim display.
Rigol MSO2072A Logic Analyzer question - Page 1
Forum section: electronics / testgear

author: jugosali
author_rank: Newbie
timestamp: December 04, 2016, 12:11:13 pm
content: HiI come from here:https://www.eevblog.com/forum/beginners/presentation-and-help-to-choose-logic-analyzer/Long story short:I have the chance to score a decent piece of kit from the company. I can do for sure (I think) with a saleae or similar, but as my company spending money is a rare thing, I would like to get a more complete unit that will be handy in the future.Regarding the logic analyzer I cant find a lot of information out there. I need to record at least 3-5 minutes in a row of low speed info (9600 bauds 232, 20Khz encoder...) Is this MSO capable providing the extra memory is enabled?Also, to review all the captured info. Does the software included allows to view on the PC side as the saleae or similar?I see there is this Pulseview-sigrok software that claims compatibility, but have not found any info or video about it applied to the Rigol case.Is there any online resource giving specifics about this subject? Mi searches have been not helpful.Thanks a lot in advance for the help.I have seen this offer that includes all the unlocks:http://www.rigol-uk.co.uk/Rigol-MSO2072A-Mixed-Signal-Oscilloscope-p/mso2072a.htm
New Uni-t ut18 voltage and continuity testers - Page 1
Forum section: electronics / testgear

author: JonnyM
author_rank: Contributor
timestamp: December 03, 2016, 07:20:42 pm
content: Have you seen the new uni-ut18 series?http://www.uni-trend.com/productslist.aspx?ProductsCateID=894&BaseInfoCateID=894&CateID=894&CurrCateID=894I lost my trusty ut15c at work and now I'm looking for a new one. The ut18 c and d looks nice and they both cost $30 on ebay but there isn't really any reviews or pictures of the board. The d model looks nice with it's big lcd but it doesn't work without batteries so the c model is maybe safer.What's your opinion?, Should I order the ut18 c or d model or the old $10 cheaper ut15c? I'll post some pictures of the board for sure.I know that uni-t doesn't make the safest meters but there isn't much that can go wrong with voltage testers.

author: fubar.gr
author_rank: Unknown
timestamp: December 04, 2016, 10:12:32 am
content: It looks really cool!I ordered the UT18C yesterday.In my opinion the C is the best of the series. For this type of meter I prefer the LEDs to the LCD screen. It is mentioned in the manual that they have an almost instantaneous response. The LCD display OTOH has a delay of about a second.I'll make a review and teardown video as soon as I get it.
VINTAGE stuff: schematics for HP 850151B - input module of Vector volt HP8508A - Page 1
Forum section: electronics / testgear

author: asilva10
author_rank: Contributor
timestamp: December 04, 2016, 04:22:04 am
content: I am looking for the schematics of the HP 850151B - input module used at the Vector voltmeter HP8508A.Any idea where I can find it?Thanks!!
Schematics of Vector Multimeter HP 8508A (not Fluke 8508A) - Page 1
Forum section: electronics / testgear

author: asilva10
author_rank: Contributor
timestamp: December 03, 2016, 04:15:01 pm
content: I am trying for more than 20 days to find schematics for HP8508A. The Service manual (130pages) does not contain the schematics and I am in need of fixing one board.Thank you!!
advantest R3361D display "Line 1111 Emulator" - Page 1
Forum section: electronics / testgear

author: mrf245
author_rank: Regular Contributor
timestamp: December 03, 2016, 01:25:45 pm
content: Hello all,My old advantest R3361D SA worked fine before, tonight I power up and after it showed advantest logo,it only shows "Line 1111 Emulator" without any other. Can some one tell me what should I do next step.Thanks anyway.BH7JUO/Mark

author: Fraser
author_rank: Super Contributor
timestamp: December 03, 2016, 02:56:58 pm
content: Check the memory retention battery.Fraser
Datalogging questions about Rigol DM3058E bench meter - Page 1
Forum section: electronics / testgear

author: Psi
author_rank: Super Contributor
timestamp: December 09, 2015, 11:21:20 am
content: Hi,Does anyone have experience with data logging on the Rigol DM3058E bench top meter.I'm interested to know what you can/cant do logging to it's internal memory and min/max/avg.1) The specs seem to say 8 - 2000ms trigger and 2000 samples per history record. But that would mean you can only do a data logging run for 66 minutes. Which seems far to short for a lot off things. So i'm probably interpreting the specs incorrectly?I see it can take a USB stick, so can i datalog for 1 week continuous using the USB stick for the extra storage?2) Does anyone know if the min/max/avg is done separately to the NVmemory. eg, if i left it running for 2 weeks would the min/max/avg reflect the entire 2 weeks or just the last 2000 samples.Thanks

author: vy73
author_rank: Newbie
timestamp: December 01, 2016, 12:58:08 am
content: ...did anyone find a solution to record more measurements to a thumbdrive?I'm currently looking for a solution to measure voltages over 2 weeks with the 0.02s setting. Also looked for a software solution but was not able to find anything.Thanks
Keysight DSO1014A - a new bug? - Page 1
Forum section: electronics / testgear

author: nfmax
author_rank: Super Contributor
timestamp: September 19, 2016, 07:11:02 pm
content: I have just found a bug with my Keysight DSO1014A, firmware version 011.04.00.04.06 SP05. Under specific circumstances, the tracking cursors stop tracking the selected waveform, where this is MATH/FFT.To reproduce:Select Default SetupApply a 1Vpp 1kHz sine wave to CH1Set CH1 to probe X1, 200mV/divSet timebase to 20ms/divTurn on FFT, Blackman window, dBV display, 10dB/divTurn on cursors in tracking mode, set both A & B to FFTAdjust A to 1.000kHz, B to 2.000kHzNow use the horizontal controls to set the FFT display to 62.50Hz/div, centre frequency 1.000kHzThe cursor no longer tracks the waveform!There seem to be other manifestations of this bug. I have seen a cursor apparently tracking the FFT trace'soldposition after a zoom/pan operation, and I have seen a cursor track only across part of the displayed trace. Sometimes the cursors seem to be unaffected by zoom/pan, but the recipe above seems to provoke it every time.Anyone else seen this? Are you there, Daniel?MaxEdit to add: If you look closely, cursor B is just to the left of the right hand edge of the scree, yet its frequency is still shown as 2.000kHz. This is also wrong!

author: Keysight DanielBogdanoff
author_rank: Unknown
timestamp: September 20, 2016, 04:07:59 am
content: Quote from: nfmax on September 19, 2016, 07:11:02 pmHi! I'll take a look at it.

author: nfmax
author_rank: Super Contributor
timestamp: November 30, 2016, 02:27:39 pm
content: Quote from: Keysight_DanielBogdanoff on September 20, 2016, 04:07:59 amAny news?

author: Keysight DanielBogdanoff
author_rank: Unknown
timestamp: December 01, 2016, 12:57:56 am
content: Yes, thanks for the thread bump and sorry for not responding sooner!It does look like a bug, but it only seems to happen at the very most extreme setting of the FFT. Can you verify?
PS (DP821 / TP340A) - Page 1
Forum section: electronics / testgear

author: metrologist
author_rank: Super Contributor
timestamp: November 30, 2016, 10:34:54 pm
content: Hi Folks,I may entertain the idea of another bench supply. I typically use a variety of switch mode single/multiple output voltage supplies. There is a used TP340A or Rigol clearance DP821).I've always been intrigued by the TP340A look, but I wish for more current at the higher voltages (I also use a Micronta dual output tracking supply, but 1A limit is cumbersome).The Rigol is not much more. Well, it is considerably more, but the difference of two nickels vs one is not really that much... I have seen (not read) discussions mostly about the Rigol DP832A, but have not looked much into any PS. I think I like the idea of 60V or 10A of the DP821, and I would just like that supply better. I also like the idea of 3 outputs, probably less than CV/CC operation, however.Can someone fill in some of the high level items I should consider?It is just for a casual hobby bench, not likely to need remote programming.
GW Instek GDS2000E - Page 1
Forum section: electronics / testgear

author: PigSpark
author_rank: Contributor
timestamp: November 28, 2016, 02:40:16 pm
content: Firmware 1.26 is available on the GW website.

author: JPortici
author_rank: Super Contributor
timestamp: November 29, 2016, 06:47:45 am
content: where? can't find it. changelog?

author: PigSpark
author_rank: Contributor
timestamp: November 29, 2016, 10:15:21 am
content: You have to register now to download firmware updates.

author: dfnr2
author_rank: Regular Contributor
timestamp: November 30, 2016, 10:28:33 pm
content: A link would be helpful, since--registration required or not--it's not obvious on the GWInstek site. What's in this release?
Up to date 2016 — USB scope or external soundcard-based scope for Android  - Page 1
Forum section: electronics / testgear

author: 001
author_rank: Super Contributor
timestamp: November 30, 2016, 02:38:08 pm
content: I don`t know what in favor nowBut I looking for USB scope for Android or or external soundcard-based scope for Android tooNot high tech but compact since Android phone in my pocket everywhereAny nowday opinions?
53220A - is that spec. correct? - Page 1
Forum section: electronics / testgear

author: carl_lab
author_rank: Frequent Contributor
timestamp: November 29, 2016, 11:37:26 am
content: I don't understand, why aging rate for 2 years is below value of 1 year aging rate:http://literature.cdn.keysight.com/litweb/pdf/5990-6283EN.pdf?id=1942617Did they swapped 1yr ansd 2yr values by mistake?For the standard oscillator (1ppm/yr) I would expect for 2 years aging something between 1 and 2 ppm (not 0.5 ppm)What does this mean?"All Timebase Aging Errors apply only after an initial 30-days of continuous powered operation and for a constant altitude ±100 m. After the first 1-year of operation, use ½ x (30-day and 1-year) aging rates shown."

author: rf-loop
author_rank: Super Contributor
timestamp: November 29, 2016, 12:00:46 pm
content: I believe it is right.Aging is most fast when XTAL is new.More long used and more slow aging typically.Best aging curve is if OCXO is continuously power on. (Example due to aging curve retract and possible other reasons.) After 5 year "pre-ageing" it may go nicely. (IF Owen temperature control is well done and perfect without long-time drift, etc)If we look more deep about these things we find whole "mystery" world. More you know, things go more complex.http://kunz-pc.sce.carleton.ca/thesis/CrystalOscillators.pdf

author: HighVoltage
author_rank: Super Contributor
timestamp: November 29, 2016, 12:04:41 pm
content: Yes, the numbers are correct, the instrument gets better over time.The uncertainty after this time of continuous use is 1/2 of the day or year value.

author: carl_lab
author_rank: Frequent Contributor
timestamp: November 29, 2016, 12:14:45 pm
content: Quote from: rf-loop on November 29, 2016, 12:00:46 pmYou said "more slow"."More slow" for me means lower "change per time".Then the "2yr" value is diffential change between t1=365 days and t2=730 days?So if you want to calculate (absolute) change from t0=0 days (after initial 30 days "warming up") to t2=730 days, you have to add 1ppm+0.5ppm=1.5ppm ?
HP 4338A Milliohmmeter BNC terminals - Page 1
Forum section: electronics / testgear

author: carloscuev
author_rank: Regular Contributor
timestamp: August 17, 2014, 08:41:26 am
content: Hi, I bought this milliohmmeter very cheap from my county's ebay-like site, It didn't had its respective mating cable (HP 16143B). So I quickly ordered this chinese kelvin clips:But it didn't worked, so I started to investigate. Turned out that the Lcur BNC is electrically isolated from anything else, with just some protection between it and ground (case). All the other BNC terminals share a common ground.As you can see that Lcur terminal looks very weird, but there are no signs of repair or so, even in the Service Manual they state that this is correct:Playing with it I connected Lcur ground to the other terminals ground and it worked, the question is: Anyone have this milliohmeter? Could they check coninuity of those BNCs outer shell between them? Anyone have the HP 16143B mating cable? Could you take some pictures from its insides to look what connections it has inside? Thanks.

author: Jay_Diddy_B
author_rank: Super Contributor
timestamp: August 17, 2014, 09:57:23 am
content: Hi,I am not familiar with this milliohmmeter, but I do the 4274 and 4275 LCR meters. The wiring of the test fixture is shown here:https://www.eevblog.com/forum/testgear/hp-4274a-lcr-meter-mini-teardown/msg399732/#msg399732This may work for your Milliohmmeter.Regards,Jay_Diddy_B

author: testpoint
author_rank: Regular Contributor
timestamp: November 29, 2016, 05:28:01 am
content: it is different as LCR, check here. the left BNC is empty to cable.
Flakey Vichy VC97 Multimeter... trash it or do you have the fix?   Help - Page 1
Forum section: electronics / testgear

author: wingryder
author_rank: Newbie
timestamp: November 28, 2016, 03:58:26 pm
content: Six months ago I bought this Vichy VC97 for cheap. Used it a couple of times.. for my limited electronics testing it seemed fine.got it out recently and it won't read the same voltage twice in a row. Or zero out for ohm check the same way.You can switch it on, measure a nine volt battery.. reads it fine. Lift off the leads and right back on and it measures 0.Same with ohms and diode function. Place leads together expecting it to go to 0 and it still says OL. Nice little meter but worthless if you are second guessing every reading. I am guessing it is just an adjustment.. but which one? I installed new batteries, I tried different test leads... acts just the same very very flakey.It was only 20 bucks but.. still (Even if you can't help me here... shoot me your favorite multimeter 40.00 to 80.00 range.)thankswingryder

author: Performa01
author_rank: Super Contributor
timestamp: November 28, 2016, 04:36:06 pm
content: If you've already tried different probes, then it has to be a contact problem with the input connectors. Check the internal connection.NOT an adjustment, for sure...

author: Arhammon
author_rank: Contributor
timestamp: November 28, 2016, 07:33:24 pm
content: Maybe you need just to clean rotary switch.

author: wingryder
author_rank: Newbie
timestamp: November 28, 2016, 10:09:18 pm
content: Well I guess it was just the test leads. I found a third set in my junk box.. and with those the VC97 straightened right up. Seems to be fine now. However glad I found this little corner of the net. I will be reading and asking in the future.thankswingryer
AC Current source (regulated)  200ma (load = 12-100 \$\Omega\$ resistive) - Page 1
Forum section: electronics / testgear

author: Jester
author_rank: Frequent Contributor
timestamp: November 11, 2016, 08:59:24 am
content: I half expected to find a small ready made board on ebay using a LM3886 or similar but no luck so far.I will be using this at 60HzAny suggestions?

author: Vgkid
author_rank: Super Contributor
timestamp: November 11, 2016, 09:08:01 am
content: Are you up to building one?

author: Jester
author_rank: Frequent Contributor
timestamp: November 11, 2016, 09:20:08 am
content: Quote from: Vgkid on November 11, 2016, 09:08:01 amI built a higher current version in the past (4 amps) based on the LM3886, that was a while back and I can't seem to find it or any blank boards. I hoped to find an OTS board or instrument.

author: 2N3055
author_rank: Super Contributor
timestamp: November 11, 2016, 09:53:30 am
content: Quote from: Jester on November 11, 2016, 09:20:08 amCare to share a bit about design? Sounds interesting...

author: Vgkid
author_rank: Super Contributor
timestamp: November 11, 2016, 09:54:19 am
content: Are you looking for any stsbility or accuracy requirement?What about a precision diff amp with a high power opamp buffer.

author: 2N3055
author_rank: Super Contributor
timestamp: November 11, 2016, 09:59:36 am
content: Quote from: Vgkid on November 11, 2016, 09:54:19 amLM3886 IS basicaly a power opamp with minimum 10x gain.... DC specs are fully specced, and if you servo it with a low offset opamp it does a pretty good job...I'm contemplating about 4 quadrant power supply based on LM3886 for some time now... Didn't have time so far to do it yet ...

author: Jester
author_rank: Frequent Contributor
timestamp: November 11, 2016, 01:07:52 pm
content: Quote from: 2N3055 on November 11, 2016, 09:53:30 amI designed it some time back, I don't recall the details of the CT.

author: Jester
author_rank: Frequent Contributor
timestamp: November 11, 2016, 01:33:02 pm
content: Quote from: Vgkid on November 11, 2016, 09:54:19 amThis will be used to calibrate an ac current measurement circuit, so short term stability (as in a few seconds) is all that is required. Accuracy is not super important because the actual current will be measured with an accurate meter.

author: Jester
author_rank: Frequent Contributor
timestamp: November 11, 2016, 04:17:22 pm
content: I will order a board based on the original design, if anyone needs a board let me know and I will order an extra

author: Jester
author_rank: Frequent Contributor
timestamp: December 04, 2016, 01:20:29 am
content: Boards are in, crude but effective. I populated the board with 25V electrolytic caps, which limits output current to about 3A rms, I will need to upgrade the capacitors to 50V if I need more current in the future.
Floating power supply in series with HV earth referenced source - Page 1
Forum section: electronics / testgear

author: wolf32d
author_rank: Contributor
timestamp: November 28, 2016, 04:24:50 pm
content: In our lab we have a good old Agilent E3631A. Its 6V floating output is connected in series with another mains earth referenced power supply.In other words the second power supply lifts the negative socket of the E3631A of a voltage V_lift.Here's the question:what is the maximum safe value of V_lift? I cannot find any data about the output-to-earth ground insulation

author: David Hess
author_rank: Super Contributor
timestamp: November 28, 2016, 07:34:05 pm
content: Page 161 of Agilent E3631A manual:IsolationThe 0-6V supply is isolated from the ±25V supply up to ±240 Vdc. Maximumisolation voltage from any terminal to chassis ground ±240 Vdc.
REK RK8512 300W DC Load Help - Page 1
Forum section: electronics / testgear

author: madeinoz67
author_rank: Newbie
timestamp: November 24, 2016, 12:59:36 am
content: Hi all,I picked up one of these during my last visit to Shenzhen, same store as I purchased my Rigol scope and also have purchased equipment on previous visits so are fairly trustworthy in terms of quality and brands which is why they are my goto place for test equipment when I'm on a buying spree in SZI've downloaded the english manual and appears that Menu is considerably different to the Manual. i.e. <Shift> 0 takes me to the menu but only has 3 things to select 1) System Set, 2) List Set , 3) Auto Test Set and then Menu Exit. There is no Config menu and I can't get into calibration mode as described in another threads on this forum.I'm trying to get the software working with it to record some battery discharge tests which first alerted me to the fact that I couldn't get into the config menu to set baud etcFirmware on boot up is showing V2.4.Stephen...

author: madeinoz67
author_rank: Newbie
timestamp: November 24, 2016, 01:25:42 am
content: ...just realised I was reading the BK precision manual so more than likely will be a difference. Doh!Could someone with this model please let me know if there is any way to configure baud rate etc?Also I'd love to know how this thing is calibratedStephen

author: singapol
author_rank: Frequent Contributor
timestamp: November 24, 2016, 04:23:13 am
content: As usual a rebranded unit but here is a more established brand..Maynuo.There is a config menu.(shift key and up,down arrows/) also note it uses dedicated usb cable/dongle.Maynuo user manual:http://www.maynuo.com/downloadfile/2009102937213561.pdfQuote

author: madeinoz67
author_rank: Newbie
timestamp: November 28, 2016, 03:14:15 am
content: Quote from: singapol on November 24, 2016, 04:23:13 amThanks for that, What I'm finding is that the menu contents is different to the manual of others like the Maynuo and BK instruments where there doesn't appear to be a config menu??? I did pick up a dedicated isolated USB/TTL interface for it.
I broke my uCurrent Gold - I think? - Page 1
Forum section: electronics / testgear

author: JohnAdriaan
author_rank: Newbie
timestamp: November 26, 2016, 12:40:23 pm
content: I've only had it a couple of weeks... It worked fine, but now it has anegative5.5-7.0mV bias.Rev 5 PCB, Serial #004118, Cr2025 @ 2.8V (when on, on mA range)With my multimeter on mV, connected to the Voltage Output terminals, and nothing connected to the Current input:When OFF, it reads 00.00mVWhen ON, it reads:nA=+04.45mVuA=-05.50mVmA=-05.50mVWhen SHORT, it reads-05.60mV.If I measure a 5.03V source through a resistor, I get5.03V through 10K (9,998ohm) resistor on uA scale:Floating=-07.02mVConnected=+507.0mV5.03V through 1K (993ohm) resistor on mA scale:Floating=-06.66 mVConnected=-01.61 mVI'm perfectly willing to accept that I've blown something: but what? Where? The fact that it still measures reasonably accurately, but with a -6mV bias, is both humorous (-06.66V) and factorable when measuring, but it is a little irritating!With thanks for any suggestions

author: evava
author_rank: Regular Contributor
timestamp: November 28, 2016, 09:24:15 am
content: Try looking on output with scope, if it is not oscillating.
Twin display multi-meter? (Meter + remote display unit) - Page 1
Forum section: electronics / testgear

author: Psi
author_rank: Super Contributor
timestamp: November 26, 2016, 10:23:57 pm
content: Hi,Does anyone know of a professional multimeter which supports a remote display module in addition to the display on the meter itself?The display on the meter doesn't need to be detachable like the Fluke 233. The multimeter simply needs an RF link to support some sort of remote display unit in addition to its own display.Has to be a modular unit and not PC/phone software connecting over BLEBonus points if the remote display unit can run from a wall power adapter in addition to batteries.

author: Muttley Snickers
author_rank: Unknown
timestamp: November 26, 2016, 10:35:42 pm
content: I do know that Keysight has one for their range of meters but it's not the cheapest thing around, from memory you would also need the bluetooth module for the meter as well, certainly worth a look anyway.Keysight Remote Display.http://www.keysight.com/en/pd-2419452-pn-U1115A/remote-logging-display?cc=AU&lc=eng

author: pascal_sweden
author_rank: Super Contributor
timestamp: November 26, 2016, 11:55:39 pm
content: Take a look at Owon. They do have some multimeters with Bluetooth support for Remote read out.

author: joeqsmith
author_rank: Super Contributor
timestamp: November 27, 2016, 02:23:19 am
content: I don't know what professional would mean of what your needs are. Maybe just a basic wireless DAQ would do what you need?At home, I'm basically running everything from GPIB using Ethernet which is on a wireless router as well.UNI-T has a wireless adapter that fits in place of their cabled one but I believe it is Bluetooth.I have an Extech EX540 with wireless built-in. They use the TI CC1101. I am not impressed at all with the meter I purchased last. There are some major quality issues with it compared with the first one I bought. They do offer ability to talk with the meter using a documented library so LabVIEW, etc is supported.Update:Looks like they do offer drivers for Windows 10 as well.

author: adranp
author_rank: Regular Contributor
timestamp: November 27, 2016, 08:58:20 am
content: Why don't you look at a solution based on a mobile phone or a tablet application?Fluke and Keysight have their mobile applications which can make the mobile phone/tablet remote displays.It all depends on your required distance between multimeter and remote display. Both solutions are based from my knowledge on Bluetooth.

author: Psi
author_rank: Super Contributor
timestamp: November 27, 2016, 09:04:36 am
content: The remote display side of things needs to be dead simple. Something that can simply be plugged in and switched on. (It will be in view of a camera).PC/Mob apps are out due to complexity and reliability.

author: pascal_sweden
author_rank: Super Contributor
timestamp: November 27, 2016, 04:32:20 pm
content: What about the Mooshimeter?https://moosh.im/mooshimeter/

author: NottheDan
author_rank: Frequent Contributor
timestamp: November 27, 2016, 05:26:32 pm
content: Are you willing to build your own remote display?https://hackaday.io/project/3525-multimeter-remote-display
Rigol 1054Z - Logic Probes possible? - Page 1
Forum section: electronics / testgear

author: made2hack
author_rank: Frequent Contributor
timestamp: December 05, 2016, 05:48:40 pm
content: Hi all,I'm not sure I understand if the 1054Z is capable of using the Logic Probes on the front mount?According to the website, rigol.eu the RPL1116 :Standard logic probe for MSO1000Z. Upgrades a DS1000Z Plus or DS1000Z-S Plus to an equivalent MSO. Includes front panel labels with MSO model number. Only works with the Plus models or as a replacement part for the MSO1000Z models.So, the 1054Z doesn't have logic option? Do I have to get necessarily a 1074Z Plus for it to work?Anyone have luck using probes with the 1054Z? Is it a matter of the hardware not being installed? I can't remember off hand Dave's teardown video. Or is it software?

author: Fungus
author_rank: Super Contributor
timestamp: December 05, 2016, 06:07:58 pm
content: Quote from: made2hack on December 05, 2016, 05:48:40 pmNo.Quote from: made2hack on December 05, 2016, 05:48:40 pmYou need one with the extra connector on the front. The 'Plus' versions have that, also the "MSO" versions.
Farnell DM131 Digital Multimeter - Page 1
Forum section: electronics / testgear

author: WaveyDipole
author_rank: Frequent Contributor
timestamp: November 27, 2016, 02:19:09 pm
content: I have a Farnell DM131, an older, DMM, the design of which dates back to 1978. It measures AC and DC volts and current as well as resistance with two scales, '' and '20M', and also temperature. Initially it was not working and the fault was relatively easy to repair once traced. It looks like the jack for the thermocouple had been replaced but was not wired correctly and an earth connection was not being made which caused erratic random readings.The DMM seems to work fine now. Voltage measurements seem accurate, current and resistance was only very slightly out when compared to my Fluke. The problem I have with it is when taking resistance readings. If I strap a resistor directly to the terminals it will give a pretty stable reading, but if I attach probes to the terminals, the reading fluctuates making it difficult to take a reading. The higher the resistance, the worse the problem and it occurs on both DMM resistance settings. This is even so with different probes and even if the resistor is strapped across the terminals and then probes are just inserted into the jacks without actually being connected to anything.I did a little checking with an oscilloscope and found that although being mains driven, the power rail is quite stable without any significant ripple, despite my not replacing any capacitors yet. With a resistor connected to the terminals and with the probes plugged in I did pick up some slight mains hum noise, which disappeared when the probes were removed - i.e. it was not present on the terminals themselves.I am wondering whether the mains hum noise being picked up by the probes is destabilizing the circuit somehow, but I don't have this problem with my other DMMs. Is this a 'feature' of older, mains powered DMMs - or specifically this model - or is this a fault condition?

author: Kleinstein
author_rank: Super Contributor
timestamp: November 27, 2016, 04:15:09 pm
content: Most DMMs use an ADC that averages over a multiple of the grid period (20 ms or 16.6 ms). This give a pretty good suppression of mains related signals. In an old meter the frequency could have drifted, making it more sensitive. Mains powered meters could have capacitive coupling - not unusual to find half the mains voltage.
Elenco GF-8026 Signal Generator repair - Page 1
Forum section: electronics / testgear

author: WolfmanTech
author_rank: Contributor
timestamp: November 27, 2016, 05:13:58 am
content: Another day, another repair post. I picked up my Elenco GF-8026 as part of a load of old computers and test equipment while volunteering in the computer lab of my local mission. Unfortunately, that is also where it picked up some of its damage, as the way the trucks were unloaded was by tossing things into old wooden apple-bins without much care. Granted, most Items were old and/or faulty and thus destined for recycling, but it was still wasteful. So, the top half of the casing was shattered by something heavy landing on it, which also cracked the board and snapped three of the ganged Alps selection switches on the front. I only recovered the broken-off ends to two switches, and I either discarded the top cover as too far gone or lost it, don't remember. Still have the handle though! I managed to repair the cracking damage to the board (as you can see in the pics), but I have yet to buy replacement switch(es) from Alps due to lack of funds. It had a sticker saying the square-wave was non-functional and showed signs of having been repaired in that area before, but I think I'll wait on that until I get the switches and case repaired/replaced.So, this will mostly be a place-holder of my current point in this project until I make some money. That said, anyone have a spare top case half or have an idea how difficult it would be to fabricate one?
Looking for schematics/detailed info about HP 8508A (not Fluke 8508A) - Page 1
Forum section: electronics / testgear

author: asilva10
author_rank: Contributor
timestamp: November 25, 2016, 05:21:47 pm
content: The user and service manuals (the latter one has 130 pages) do not have the schematics of the boards.I would like to change some aspects of this old equipment for a college project and any additional information (in particular, the schematics) is very welcome. Thank you!!

author: singapol
author_rank: Frequent Contributor
timestamp: November 26, 2016, 02:27:59 am
content: This could be a big file..Fluke 8508A Service manual -https://doc.xdevs.com/doc/Fluke/8508A/8508A___smeng0100.pdf

author: asilva10
author_rank: Contributor
timestamp: November 26, 2016, 03:15:04 pm
content: Hi, thank you for the attachment.Actually, I am looking for the electronic schematics for the HP 8508A and the link is for Fluke 8508A (same model number!!). Nonetheless, thank you for your attention.
Extender for Dranetz 626 plugins - Page 1
Forum section: electronics / testgear

author: perdrix
author_rank: Frequent Contributor
timestamp: November 26, 2016, 02:43:35 pm
content: I've made an extender for this.Piccie:Gerbers:http://www.perdrix.co.uk/Dranetz 626/Dranetz 626 Extender Gerbers.zipDave
Gw Instek GDM-8055 Multimeter Teardown - Page 1
Forum section: electronics / testgear

author: vasi_ro
author_rank: Unknown
timestamp: November 25, 2016, 01:25:20 pm
content: New multimeter in my lab.

author: vasi_ro
author_rank: Unknown
timestamp: November 25, 2016, 01:26:33 pm
content: more images

author: vasi_ro
author_rank: Unknown
timestamp: November 25, 2016, 01:31:03 pm
content: last set

author: Kleinstein
author_rank: Super Contributor
timestamp: November 25, 2016, 02:00:54 pm
content: Looks like a rather simple circuit. Just the 2 LM399 are really a surprise - even 6 digit meters usually have only one.

author: vasi_ro
author_rank: Unknown
timestamp: November 25, 2016, 02:11:48 pm
content: I think one of Lm399 it's the main refernce and the other one it's used for self calibration.From the user manual :GDM8055 feature internal calibration using known referenceresources. Multimeter automatically calculates the correction factors and stores it inThe calibration memory.I was unable to find the service manual for this meter...
HP 53131A counter option H05? - Page 1
Forum section: electronics / testgear

author: Jwalling
author_rank: Unknown
timestamp: November 23, 2016, 06:50:10 pm
content: Picked up an HP 53131A counter with option 030 010 and H05. I know what the first two are, but does anyone know what option H05 might be?A phone call to a support engineer at Keysight couldn't find any information on it.Thanks.

author: Jwalling
author_rank: Unknown
timestamp: November 23, 2016, 07:29:55 pm
content: Quote from: plesa on November 23, 2016, 07:25:39 pmI does not have an N connector. Also, I checked the HP part number (thinking like you) on the prescaler board, and it's definitely the 3GHz board.

author: plesa
author_rank: Frequent Contributor
timestamp: November 23, 2016, 07:38:52 pm
content: Quote from: Jwalling on November 23, 2016, 07:29:55 pmThat's strange. Does it have H05 printed on read panel or there is sticker with h05? Maybe it is special version for army/navy.

author: TheSteve
author_rank: Unknown
timestamp: November 23, 2016, 07:40:18 pm
content: I believe it means it included the US NAVY CLIP/English manual set.

author: plesa
author_rank: Frequent Contributor
timestamp: November 23, 2016, 07:41:52 pm
content: Option H05 provides internal CIIL compatibility or Internal MATE programming. MATE U.S. Air Force Modular Automatic Test Equipment system application.SCPI is an industry standard providing a single set of commands that control a wide variety of measurement instruments. CIIL language is also available as an option for MATE system compatibility.

author: HighVoltage
author_rank: Super Contributor
timestamp: November 23, 2016, 07:44:47 pm
content: Quote from: plesa on November 23, 2016, 07:41:52 pmWhat does that mean in plain english?Is it a military expression?

author: Jwalling
author_rank: Unknown
timestamp: November 23, 2016, 07:46:39 pm
content: Quote from: plesa on November 23, 2016, 07:38:52 pmIt's a sticker on the rear bezel. A picture...

author: Jwalling
author_rank: Unknown
timestamp: November 23, 2016, 07:49:45 pm
content: Quote from: plesa on November 23, 2016, 07:41:52 pmVery interesting. Where the hell did you dig that up?
METEX MS-9170 combo meter/power supply/ counter/ generator ? - Page 1
Forum section: electronics / testgear

author: 001
author_rank: Super Contributor
timestamp: November 24, 2016, 08:21:02 pm
content: METEX MS-9170 combo meter/power supply/ counter/ generator…Any opinions?? Thanx!

author: nctnico
author_rank: Super Contributor
timestamp: November 24, 2016, 08:35:59 pm
content: This thing is sold under several brands and has been for sale for maybe 2 decades or more in various incarnations:https://www.eevblog.com/forum/testgear/tenma-universal-test-center-72-5085/https://www.eevblog.com/forum/reviews/metex-universal-combined-test-instrument-systemsstations-a-look-inside/

author: jancumps
author_rank: Unknown
timestamp: November 24, 2016, 08:52:51 pm
content: good enough for mePaid 50€ second hand a few years ago.

author: Neganur
author_rank: Unknown
timestamp: November 24, 2016, 09:05:54 pm
content: It's a nice unit, just don't pay too much for it since it's getting quite old now compared to other stuff on the market.

author: radhaz
author_rank: Regular Contributor
timestamp: November 25, 2016, 03:07:10 am
content: They certainly have gotten their design costs out of that thing.

author: 001
author_rank: Super Contributor
timestamp: November 25, 2016, 03:24:32 pm
content: multimeter METEX MS-9170 looks not so bad with it`s 40000 Counts, Bargraph, True RMS and interface, isn`t it?

author: kripton2035
author_rank: Super Contributor
timestamp: November 25, 2016, 03:38:29 pm
content: I had a 9150 some ... 20 years ago ! was a nice unit.the only thing I did not like was that you have to install a 9v battery for the multimeter to work.don"t know if the 9170 has that battery too ?I changed it against hameg modules, part by part, then sold the whole unit on ebay.
anyone insterested in Tek 7404 parts ? - Page 1
Forum section: electronics / testgear

author: free_electron
author_rank: Super Contributor
timestamp: November 22, 2016, 01:48:14 am
content: i have bits and parts of this machine.- lcd display , motherboard ( incl cpu and ram ) , cdrom , power supply , digitzer board ,basically i don't have HDD , front panel and the plastic 'clothing'.thought i'd throw it out here before i toss it ...shipping inside us only ( international is too much hassle ).fair offers accepted.
Rigol DS1000D | Sampling Mode cannot be changed via SCPI - Page 1
Forum section: electronics / testgear

author: firehacker
author_rank: Contributor
timestamp: November 21, 2016, 12:40:59 pm
content: Hi guys.Looks like there is a bug (yet another one, right) in the Rigol DS1000D firmware. My scope is DS1052D, revision 00.02.06.It turned out that sampling mode (Equ-Time vs Real-time) can be queried via SCPI, but unlike other acquisition parameters, it cannot bechanged.Since I am making a tool for automated signal analysis, I would like to know whether this bug is present in other revisions and product versions (100 MHz version and/or version without Logic Analyzer).Please, try to reproduce and tell if it worked with your scope (specify your model, revision).Code::ACQUIRE:MODE? <----- gives REAL_TIME:ACQUIRE:MODE EQUAL_TIME:ACQUIRE:MODE? <------ still gives REAL_TIMEIf I manually change sampling mode via menus,Code::ACQUIRE:MODE? <----- gives EQUAL_TIME:ACQUIRE:MODE REAL_TIME:ACQUIRE:MODE? <------ still gives EQUAL_TIME

author: ebastler
author_rank: Super Contributor
timestamp: November 21, 2016, 01:58:24 pm
content: Have you tried ":ACQ:MODE ETIM", or "...RTIM", as described in the manual?Regards,Juergen

author: firehacker
author_rank: Contributor
timestamp: November 21, 2016, 02:24:04 pm
content: Quote from: ebastler on November 21, 2016, 01:58:24 pmI was about to reply "no, there is no RTIM and ETIM in the manual, there are REAL_TIME and EQUAL_TIME" when I realized that I have actually opened wrong PDF file (oscilloscope programming reference) — for DS1000CD instead of DS1000D.ETIM and RTIM work just perfect! Thank you for finding out cause of the problem.Anyway, even if DS1000D(E) series scope expects "RTIM", I would not surprise if there is a breakpoint in revision number where earlier versions expect "REAL_TIME" while more recent versions expect "RTIM" as per SCPI reference. Like we had a discrepancydiscussed here.

author: ebastler
author_rank: Super Contributor
timestamp: November 21, 2016, 02:58:38 pm
content: Hey, glad that this was easy to solve. But I agree that it is an annoying interface design by Rigol: Returning "EUQAL_TIME" as the output, but expecting "ETIM(e)" as the input is bound to cause confusion!