hybridfree/eevblog-posts huggingface dataset:
Marconi 6960 power meter - Page 1
Forum section: electronics / testgear

author: Bud
author_rank: Super Contributor
timestamp: July 15, 2014, 01:49:09 am
content: Got this box a while ago for almost nothing, but with no power sensor head. Finally got time to look at it and may be build a replacement sensor head. Nothing much exciting inside beside may be a 0dB leveled 50MHz power reference. Also there is a interesting big blue electrolytic capacitor that can be seen on the left side in one of the pictures below, the cap body is hex shaped, like a big hex nut, though the top of the cap is round. Anyone knows why would they make capacitors shaped like that?The service manual with schematic is available from here (scroll down to Marconi H6960 service manual)http://www.ko4bb.com/manuals/index.php?dir=Marconi

author: Vgkid
author_rank: Super Contributor
timestamp: July 15, 2014, 03:24:39 am
content: That is a rather interesting meter, I figured that the 50Mhz power reference would be more complex.

author: Richard Head
author_rank: Frequent Contributor
timestamp: July 15, 2014, 05:26:55 am
content: The power meters are a dime a dozen. The measurement head is what you pay an arm for.Same for the Agilent, Boonton, Gigatronics etc.Have a look at the Minicircuits USB power meter. It's quite nice, but pricey.

author: Bud
author_rank: Super Contributor
timestamp: July 15, 2014, 06:27:41 am
content: I do not much need a minicircuits meter or other meter, this is just an exercise for fun. I already assembled the chopper part of the head, not a rocket science. For the RF power detector part of the head i will be trying to use one of my ADI RF Power detector chips. A nasty surprize was that the sensed RF and converted to DC voltage into the chopper input has to be negative. But i think there is a way to generate negative supply in the sensor head using chopper control signals. So will work on it as the next step.And by the way minicircuits is hated outside of the US for their insane shipping charges.

author: blackbird
author_rank: Regular Contributor
timestamp: February 09, 2018, 08:34:07 am
content: Any progress with your power meter?
LAP-C 16064 or Digital Discovery? - Page 1
Forum section: electronics / testgear

author: IAmBack
author_rank: Regular Contributor
timestamp: February 09, 2018, 08:57:28 am
content: Hello.I know specs of both devices. But I would like to hear from users who "challenged" to use both devices. Mainly form "analyzer" point of view.I want to use these devices for FPGA mainly.Regards.
DMMCheck Plus to start production mid-March    FYI - Page 1
Forum section: electronics / testgear

author: ez24
author_rank: Super Contributor
timestamp: February 08, 2018, 08:54:28 pm
content: FYI -Quotehttp://shop.voltagestandard.com/

author: bitseeker
author_rank: Super Contributor
timestamp: February 08, 2018, 11:37:00 pm
content: Also note that orders will begin in March as well. Pre-orders were being taken prior to this week, but that has been suspended. The item currently appears as "out of stock."

author: tautech
author_rank: Super Contributor
timestamp: February 09, 2018, 12:38:22 am
content: Let's tie these 2 threads together:https://www.eevblog.com/forum/testgear/group-buy-proposal-voltagestandard-dmmcheck-plus/
Replacement button for Agilent E36xx power supply - Page 1
Forum section: electronics / testgear

author: Jester
author_rank: Frequent Contributor
timestamp: January 18, 2018, 02:23:49 pm
content: The momentary push button for the CC Set feature developed a crack on my "go to" power supply and will soon break, so I'm looking for a replacement without the Keysight $100 (or what ever it is) minimum price tag.The service manual lists the switch as Agilent 3101-3115, if I can cross reference this to an actual Mfg part # I can likely order it from Digi-Key for a dollar or so.Does anyone have a cross reference for this switch or the button cap?

author: iainwhite
author_rank: Unknown
timestamp: January 18, 2018, 03:13:07 pm
content: I am not aware of one. I recall a similar discussion (sorry, can't find the thread..) that ended up with a suggestion to 3d print a replacement button.As you say, anyone that has stock of the OEM buttons will probably want big $$ for them.

author: texaspyro
author_rank: Super Contributor
timestamp: January 18, 2018, 08:19:00 pm
content: The buttons are most likely a custom HP built part and not available from another supplier.If the button breaks you can probably just glue it back together. I'd first try a plastic welding solvent (methylene chloride based... from a hobby shop). If the plastic does not work with the solvent, try superglue.A 3D printed button would be your best bet, but I have cast replacement buttons out of epoxy using a silicone rubber (or modeling clay) mold. The hard part is making the hole for the switch shaft.

author: SkyMaster
author_rank: Frequent Contributor
timestamp: January 18, 2018, 10:13:24 pm
content: Quote from: Jester on January 18, 2018, 02:23:49 pmJester,The HP/Agilent/Keysight Part Number 3101-3115 is for the "Switch-Push Button Momentary 0.5A 250V PCB" without the button, according to the Keysight search engine, the switch is "Obsolete".The button Part Number is 0371-8624 and the description is "KEY CAP - GRAY".Unfortunately, 0371-8624 returns a "No Matches Found" on the Keysight website.But the white Key Cap seems to be available. The Part Number is 0371-3806, description is "Key-Cap rectangular ABS Cycoloc White".The white Key-Cap is only$2.99 US.Let us know how much they charge for shipping. Really, check with them; you could get lucky.P.S. I have a HP E3617A, and I like it.

author: iainwhite
author_rank: Unknown
timestamp: January 19, 2018, 04:45:51 pm
content: I found another thread on this subject...https://www.eevblog.com/forum/repair/agilent-e3620a-psu-push-button-knob-repair/

author: Jester
author_rank: Frequent Contributor
timestamp: February 08, 2018, 01:51:49 pm
content: Update ........ Found an OTS button at Digi-Key, arrived this morning, $0.26 perfect fit.https://www.digikey.com/products/en?keywords=EG1879-ND%20
Voltlog's pocket DMM review.  - Page 1
Forum section: electronics / testgear

author: wilfred
author_rank: Super Contributor
timestamp: February 07, 2018, 06:19:42 am
content: I'm a fan of Voltlog's channel and he has just done a cheap pocket DMM review. So whilst Dave contemplates his navel on a comprehensive shootout why not check it out.It is a practical down to earth review that should help you make a better choice.FWIW I have the UNI-T 120C and it works for me pretty much as Voltlog's review suggests. The one thing I'd like to add is that probe storage is enhanced by having the plastic pillars to wind the leads around. I think ease of unpacking and repacking the leads should be a top criterion for purchase. I hate poking leads back inside the case when it becomes like straightening spaghetti.

author: Fungus
author_rank: Super Contributor
timestamp: February 07, 2018, 11:36:00 am
content: Looks like he has almost the same meters as me:

author: Fungus
author_rank: Super Contributor
timestamp: February 07, 2018, 11:41:08 am
content: So... Voltlog thinks the slot in the case of the black one will prevent you from closing the lid with it switched on?

author: Fungus
author_rank: Super Contributor
timestamp: February 07, 2018, 01:05:49 pm
content: Quote from: wilfred on February 07, 2018, 12:06:35 pmThat case is a complete pain in the ass IMHO.The choice between the other two is purely personal.

author: stj
author_rank: Super Contributor
timestamp: February 08, 2018, 09:26:34 am
content: the AN8203 looks like it's based on a DM0660 or DM1106 with the config in an eeprom!
Keysight 34465A Factory Cal - Page 1
Forum section: electronics / testgear

author: Kelbit
author_rank: Regular Contributor
timestamp: February 07, 2018, 10:30:41 pm
content: We just got a new Keysight 34465A at work. The factory calibration certificate was dated at the end of July 2017, which means we'll need to send it out for cal in six months to maintain the 12-month internal.Is this usual? I was under the impression that distributors generally are supposed to push these units out the door within a couple months of manufacture. Some users on here even had units with orange sell-by stickers back when these meters first came out (see:https://www.eevblog.com/forum/testgear/keysight's-new-34465a-(6-5-digit)-and-34470a-(7-5-digit)-bench-multimeters/175/).I'm a little annoyed that we'll have to send this one out again so quickly. I'm not worried about the cost, more the hassle - there is no local cal lab in our city so we have to ship it to Vancouver, which takes time and effort.

author: Mr. Scram
author_rank: Super Contributor
timestamp: February 07, 2018, 10:34:14 pm
content: As I understand it, many places calibrate new equipment when it comes in anyway.

author: Kelbit
author_rank: Regular Contributor
timestamp: February 07, 2018, 10:35:57 pm
content: Quote from: Mr. Scram on February 07, 2018, 10:34:14 pmWe generally don't, not because of cost, but because it adds additional lead time and we usually buy new instruments on an as-needed basis.

author: Svgeesus
author_rank: Regular Contributor
timestamp: February 08, 2018, 01:34:47 am
content: Unfortunate timing. Keysight says that if the original cal is less than 6 months before the end-user turn on date, your 12 months starts when you turn it on; otherwise, it is 12 months after original cal date.Maybe see if you can return it and get another one? As another point of comparison, my 3446565A cal date was3 daysbefore I received it

author: coromonadalix
author_rank: Super Contributor
timestamp: February 08, 2018, 03:53:40 am
content: have you tried Transcat they can do Gossen meters and lot of other brands, they are located in Montreal Quebec under Ulrich Metrology
Big Marconi Scope teardown (x2) - Page 1
Forum section: electronics / testgear

author: Cliff Matthews
author_rank: Unknown
timestamp: February 08, 2018, 12:43:00 am
content: Paul (Mr Calson's Lab) shows-off Lab #2 and 2 vintage monster scopes.https://youtu.be/tXYp0C1mYQw?t=186
Ivytech8711 vs Maynuo9711 vs Rek8511 dc load - Page 1
Forum section: electronics / testgear

author: zed65
author_rank: Contributor
timestamp: February 01, 2018, 05:16:17 pm
content: I've just got me a cheap Ivytech8711 dc load. When opening it I expected to see another B&K clone, an sure it looks like all the other ones but there are some small differences.Input protection MOV/PTC, nah screw them.There are a footprint for a small IC in the back U31 that is missing on mine. Anyone know what that is?It also missing some PTC back right in picture.The TL074 are SMD vs DIP package.It says ver 3.1f2 when I boot it up.I can connect it through a USB-TTL converter via Maynuo software.Ivytech8711Maynuo9711Rek8511

author: BillB
author_rank: Unknown
timestamp: February 06, 2018, 08:40:30 pm
content: Saw this one on fleabay for a cheap price and was considering it over the slightly higher priced Maynuo 9710. How has it been performing so far?

author: zed65
author_rank: Contributor
timestamp: February 07, 2018, 08:03:06 pm
content: It has performed as expected (for now atleast).Still wondering if I should add those extra PTC at input though.Any one know what the U31 are? I can't seem to find a picture that shows the partnumber on it.

author: TurboTom
author_rank: Super Contributor
timestamp: February 07, 2018, 08:54:35 pm
content: U31 could be the driver for a current monitor output. IIRC my Maynuo has got a BNC at the back side for this purpose. It's of limited use though since it's connected to the load's input negative. The pinout of U31 suggests that it's a dual opamp with only one amplifier actually in use, so probably something like a TL082, LM358 or similar.Cheers,Thomas
Rohde CBT Bluetooth Tester Teardown/CMOS battery Repl. - Page 1
Forum section: electronics / testgear

author: SoundTech-LG
author_rank: Frequent Contributor
timestamp: February 06, 2018, 02:23:50 pm
content: Hi,We got this from our UK division, plugged it up, switched it on, it stuck at the BIOS screen. Hooked up external KYBD, hit DEL, and set all COS date/time settings, saved and it booted. Powered off. Tried it again, working still. Power off over the weekend, came in stuck at BIOS screen again. I decided the CMOS battery is dead. Tore it down to get to it. It's in the Front Panel assy, like a lot of other R&S models. The disassembly of this unit however compared to older larger models is much more difficult, using tiny flat head3mm (I think) screws. Everything fits together like a Swiss Watch. Spent a few hours with all this just to get the battery out. Fortunately we had a CR2032 button cell. The old battery had just 0.476V on it. Must have sat unplugged for a while, or the battery just died. Here's some pics to look at.

author: PedroDaGr8
author_rank: Super Contributor
timestamp: February 06, 2018, 04:33:47 pm
content: I would definitely backup that HDD because in time they do fail. Otherwise, noce teardown of an interesting specialty instrument.

author: SoundTech-LG
author_rank: Frequent Contributor
timestamp: February 07, 2018, 03:21:36 pm
content: Yep, the hard drives do die in these. We have a bunch of R&S CMD60 DECT Radio Comm testers, and a few of those have died. Fortunately one of our team members began backing those drives up. Now if one dies we can sometimes recover... depending on Options installed.
Rhode and Schwartz RSCommander software - Page 1
Forum section: electronics / testgear

author: boumboauto
author_rank: Contributor
timestamp: February 09, 2018, 06:58:46 pm
content: Hello,I was looking for R&S software review, especially to control a RTB2000 via LAN network using RScommander. I wanted to know how the oscilloscope interface works and how eaily it can be configured remotely.David

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: February 09, 2018, 07:08:38 pm
content: You don't generally need any software for most remote operation on the RTB - you have a full front-panel interface via the web interface, and using the USB interface you can pull various file formats of the latest capture off a virtual USB drive

author: boumboauto
author_rank: Contributor
timestamp: February 09, 2018, 07:36:37 pm
content: Thanks, that's good news, I didn't know how RTBs behaved once plugged. If they contain a tiny web server and http interface that's perfect.I want buy that for work because they use 10 "real" bits ADCs and seems to be very good for the priceThanks for the infoDavid

author: boumboauto
author_rank: Contributor
timestamp: February 09, 2018, 07:38:22 pm
content: Oh Mike by the way, I was looking at your review of the Owon vds3104 last night,great teardown and demo of the software ! I'll buy one of these as well for field operations, only 8 bits but they are ok for the job.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: February 10, 2018, 01:19:16 am
content: For portable use, unless you really need the small size, I'd go for the Micsig Tbook Mini over the Owon - bigger screen, more traces, better UIRTB2004 web interface :https://youtu.be/mcgJSKxj0i0?t=269Data access via USBhttps://www.rohde-schwarz.com/uk/products/test-measurement/oscilloscopes/rtb2000videos/rtb2000-import-and-export-of-data-and-settings-via-usb_231068.htmlMicsig Tbook Mini

author: lundmar
author_rank: Frequent Contributor
timestamp: February 10, 2018, 02:26:22 am
content: Quote from: boumboauto on February 09, 2018, 06:58:46 pmIf you are on Linux you could givehttp://lxi-tools.github.ioa try. It recently gained screenshot support for the RTB2000 series (tested with RTB2004).

author: boumboauto
author_rank: Contributor
timestamp: February 10, 2018, 02:14:57 pm
content: Thank you all for your help!
R&S CMU200 Reference Frequence Unlocked message  - Page 1
Forum section: electronics / testgear

author: hafrse
author_rank: Regular Contributor
timestamp: January 25, 2018, 09:07:35 am
content: Hello,My CMU200 started to display "Reference Frequence Unlocked" every about 10 sec. the trace is not "fast" as before probably because of this unlock problem. Replaced the Rerefrence board but without any success.Ny clues where the problem can be?Thanks

author: Ringmodulator
author_rank: Regular Contributor
timestamp: February 07, 2018, 01:44:47 pm
content: Check ste settings.If the external 10Mhz ref is active and no signal is fed to the 10Mhz port, this can result in such a behavouir.So make sure, that the CMU really uses the internal ref.
Super old gear - Hartmann & Braun - thermocouple devices tester - Page 1
Forum section: electronics / testgear

author: ludek
author_rank: Newbie
timestamp: February 06, 2018, 01:41:55 am
content: Hi. Few days ago I discovered Max Koschuh's video blog. And then I found this video:(teardown part 6:41 (https://youtu.be/mCFpP9fodJY?t=6m41s))1958 test equipmentHave you seen gear like this? (photos? YouTube videos?)The quality of this "tester" is so high. This is why I'm writting thisThis is soo beautilull...

author: Nauris
author_rank: Regular Contributor
timestamp: February 06, 2018, 03:12:42 pm
content: Interesting way to do all wiring with rigid noninsulated wires. Looks a bit like pipes running in some oil refinery.
UEI UTLDM2 actual UEI? - Page 1
Forum section: electronics / testgear

author: jayjr1105
author_rank: Regular Contributor
timestamp: February 06, 2018, 08:09:14 pm
content: In the market for a sub $100 meter. I really liked the UEI from the $100 DMM shootout from 2010 but then I found out UEI stopped making all but clamp meters. So I ordered a B&K 2709B.Then I found this guy...https://www.trutechtools.com/UEI-UTLDM2-Auto-Ranging-Digital-Multimeter_p_4960.htmlAnyone know if it's just a cheap chinese rebrand or similar to the DM393?Edit: The price on Amazon may have answered my own questionhttp://a.co/9B5eP76
Looking for an HP8604A manual - Page 1
Forum section: electronics / testgear

author: tkamiya
author_rank: Super Contributor
timestamp: February 06, 2018, 01:15:05 am
content: I just acquired an HP 8604A Multifunction Synthesizer. A problem I have is, I cannot find ANY manuals that are publically available. All that show up in google searches are behind paywalls, and suspicious looking websites that registered huge number of domain names.Does anyone know where I may download one? Or willing to share a pdf copy??

author: wn1fju
author_rank: Frequent Contributor
timestamp: February 06, 2018, 02:40:29 am
content: Are you sure you don't mean HP 8904A, not HP 8604A? If it's the 8904A, there are lots of free manuals on HP's site, keysight.com.

author: tkamiya
author_rank: Super Contributor
timestamp: February 06, 2018, 03:53:54 pm
content: That made a big difference. Oddly, I went to my box few times to make sure I was naming it right.Thank you for pointing it out for me.
DP832 channel 1 UR - Page 1
Forum section: electronics / testgear

author: RustyCaliper
author_rank: Newbie
timestamp: February 04, 2018, 07:37:05 pm
content: Hi Forum,I have an issue with my Rigol DP832. Something seems wrong with the current sensing on channel 1. It displays the mode as UR (unregulated) and shows an actual current of 0 A. Apparently it's a mechanical issue becuase the issue disappeared when I disassembled the unit, but unfortunately reappeared when I reassembled it. Knocking on the top board seemed to "fix" it. So likely bad connector/broken soldering joint.However, I'm unable to locate the issue and I do not have any docs. I've done my RTFMing:https://www.eevblog.com/forum/testgear/dp832a-problem-ch1/msg424491/andhttps://www.eevblog.com/forum/beginners/nonsense-behaviour-of-rigol-dp832/msg575509/andhttps://www.eevblog.com/forum/testgear/another-issue-with-the-rigol-dp832-power-supply-sense-wires-carrying-3-amps!/ andhttps://www.eevblog.com/forum/testgear/what-is-actually-fixed-in-rigol-dp832(a)-rev3/-- however no real leads.My top board HW rev is DP832A V2.10 2013-03-26. Any help greatly appreciated.Thanks, Rusty

author: _Wim_
author_rank: Super Contributor
timestamp: February 04, 2018, 09:14:10 pm
content: Does the output itself work correctly? Does the voltage measurement still work? If yes, I would expect it would be quite easy to follow the signal from the shunt resistors back to the ADC/Processor (not to many components in between I guess).I would also expect channel 1 and channel 2 to be fairly identical, so it should be possible to do a side by side comparison between the two when tracing back the signals.

author: Pinkus
author_rank: Frequent Contributor
timestamp: February 04, 2018, 09:36:20 pm
content: I would open the cover and use a non conductive (e.g. plastic) stick to press on different PCB areas / components to narrow down the area. If it is a cold joint is is usually easy then to find the problem.However if it is a broken trace with a micro crack on an inner layer it will become more difficult.

author: RustyCaliper
author_rank: Newbie
timestamp: February 05, 2018, 05:22:29 pm
content: Hey there, thanks for your suggestions. I believe the culprit in my case was J15, a two pin header that seems to feed the current sense resistor. It was optically *completely* inconspicuous, but since I've replaced it, it hasn't shown the error since. The contacts and everything looked completely pristine. Interesting...All the best, Rusty

author: _Wim_
author_rank: Super Contributor
timestamp: February 06, 2018, 05:01:17 am
content: Quote from: RustyCaliper on February 05, 2018, 05:22:29 pmGlad to hear you could fix it, and thanks for reporting back what caused it.
Tektronix 2235 help - Page 1
Forum section: electronics / testgear

author: spinach
author_rank: Newbie
timestamp: January 31, 2018, 04:22:49 pm
content: Sorry for the really simple questionI've just acquired a Tektronix 2235, AN/USM-488 version at a really great price from what I see.When it arrived there was something rattling around inside so I popped the back and sides off and whatever is rattling appears to be a black cover inside the PSU.The thing is I don't do mains. Am I safe to open the PSU if it's not been plugged in for a week?I'd just really like to keep what seems like a really nice scope without forking out any cash to get something simple fixed.

author: David Hess
author_rank: Super Contributor
timestamp: January 31, 2018, 05:23:49 pm
content: Yes, it is safe to open after a week. Everything will have discharged.

author: tggzzz
author_rank: Super Contributor
timestamp: January 31, 2018, 05:42:25 pm
content: Quote from: spinach on January 31, 2018, 04:22:49 pmIf you are poking around inside, get the service manual and familiarise yourself with the locations of the dangerous voltages. They will be near the mains input, the switched mode power supply, and the EHT associated with the CRT.

author: spinach
author_rank: Newbie
timestamp: January 31, 2018, 07:33:25 pm
content: Great thanks.I've got both the service and operation manuals so will take some time to look at them.I just need to find some probes that aren't going to cost me an arm and a leg after UK shipping / import duty now.

author: markce
author_rank: Regular Contributor
timestamp: February 02, 2018, 05:36:34 pm
content: If you want quality probes:- cheap: used tektronix probes- new: Testec LF-312 or MF-312Just my personal preference.

author: spinach
author_rank: Newbie
timestamp: February 06, 2018, 03:58:53 pm
content: There was a plastic cover insude the psu that had come off the vertical mounted board.It's all working except it whines loudly for 30 minutes or so. Front panel switches are a little tempremental but all working
hack of fluke 9500 - Page 1
Forum section: electronics / testgear

author: pasta2018
author_rank: Regular Contributor
timestamp: February 05, 2018, 02:20:56 pm
content: Since for the 9500B 1100 or 3200 option,the calibtation and adjustment procedure is the same. So the hardware of them might also be the same. Could it be possible to hack?In the back there is a "factory set", as jumper 6 is used for firmware upgrade, but another two jumpers are not introduced. And the manual says there is a second password for factory user cal,which is not given in the manual.
Hantek pc oscilloscope issue - Page 1
Forum section: electronics / testgear

author: hussamaldean
author_rank: Unknown
timestamp: February 05, 2018, 06:39:24 am
content: Hi all,i have PC oscilloscope Hantek 6022BE but it has weird issue which is it reads the wrong voltage despite the input is up to 35V. However, when the input voltage is below 4.71V it works just fine but once the voltage is above 4.71V it clamp it to 4.71Vfor example a 10V DC from my power supply and it is reading 10V on PSU and multimeterbut the oscilloscope shows only 4.71Vany solution or the input protect has some issue ?

author: daybyter
author_rank: Frequent Contributor
timestamp: February 05, 2018, 07:06:42 am
content: Uhm...it should show 5v ?For more than 5v input, use the x10 setting of the probes.But better post your problem in the 6022be thread:https://www.eevblog.com/forum/testgear/hantek-6022be-20mhz-usb-dso/?topicseen

author: Kean
author_rank: Unknown
timestamp: February 05, 2018, 07:59:11 am
content: This particular issue is discussed in that long threed.Seehttps://www.eevblog.com/forum/testgear/hantek-6022be-20mhz-usb-dso/msg359786/#msg359786

author: hussamaldean
author_rank: Unknown
timestamp: February 05, 2018, 01:00:11 pm
content: Quote from: Kean on February 05, 2018, 07:59:11 amI read the issue and it doesn't apply in my case because I was able to measure voltage beyond 5v like 12 and 24 volt directly without any issue

author: Kean
author_rank: Unknown
timestamp: February 05, 2018, 02:16:37 pm
content: That isn't what you said in your first post.If you want to measure voltage above 5V you must use a x10 probe with this model.35V is just the specfied maximum that it can handle without damage - but still requires x10 problem to scale the voltage down.

author: hussamaldean
author_rank: Unknown
timestamp: February 05, 2018, 02:17:46 pm
content: Quote from: Kean on February 05, 2018, 02:16:37 pm?I tried and nothing changedit seems I burnt it somehow
GOS-3310 , NRI 2500 , or S3000A 10Mhz oscilloscope Technical question - Page 1
Forum section: electronics / testgear

author: LoneTech
author_rank: Contributor
timestamp: February 04, 2018, 11:53:57 pm
content: HI, I'm working on this scope to give to my nephew (12Yrs old) who is interested in learning electronics , it's been in closet for who knows how long and i thought it might be a good starter scope for him.So here's the issue I'm having with it.Voltage across C101 is roughly 1600 Volts..the voltage across C103 starts out around 1130V then slowly drops off to under 700V..at which time the trace is completely gone from the CRT..I'm thinking the caps are faulty, or at this point it's the only thing i can think of that would cause it..my question is..I can't find these electrolytic capacitors anywhere..So could these be swapped out for 0.47uF 1600V mylars, or polyester type caps?

author: tautech
author_rank: Super Contributor
timestamp: February 05, 2018, 10:06:46 am
content: Quote from: LoneTech on February 04, 2018, 11:53:57 pmQuoteWhich is a bit concerning seeing they're only rated to 1500V.QuoteThey won't be electrolytic, not at that voltage.Dipped disc ceramic is most often used in this application and of multi layer type.Now just what the unit of 0.5 is....is it 0.5 uF ?Looking hard at the schematic, it appears so, so 0.47 being the common value available is where I'd go too......BUT having a sanity check with several scope schematics I have on file 10 nF seems a more common value for the DC restorer so my guess 0.5 is 5 nF.Something like these is what I'd use:https://www.aliexpress.com/store/product/Switching-2000V-4700PF-2KV-new-and-original/607624_32710914014.html?spm=2114.12010612.0.0.31767be3XMPq2NThese faults can be tricky to fix, I have had HV zeners fail but other than the high value resistors I think you're on the right track.Best of luck for the nephews sake.
Proper connector for EZ-hook XKM? - Page 1
Forum section: electronics / testgear

author: bitwelder
author_rank: Super Contributor
timestamp: February 04, 2018, 03:38:46 pm
content: After discovering the (excellent!) OpenTechLab channel, that was the first of the Dave's guest videos, I decided to buy a set of EZ-Hook XKM from Digikey.Now that I have them, I see that the slot with the connection pin seems to be a bit too small to mate properly with a standard female Dupont from the logic analyzer cable.What should I use it instead? After removing the squared plastic shell from the dupont, the metal socket itself seems to fit reasonably well. So perhaps just cover its crimped end with a bit of heat-shrink? Or should I hunt for a different connector?

author: phil from seattle
author_rank: Super Contributor
timestamp: February 04, 2018, 05:27:42 pm
content: It's not the "receptacle" but the plastic case that doesn't fit. I have the same problem and don't use the plastic casing but rather shrink wrap. Not a professional looking but it gets the job done.

author: CustomEngineerer
author_rank: Frequent Contributor
timestamp: February 05, 2018, 02:37:14 am
content: Agree with Phil. I bought a set of the EZ-Hook XKM grabbers from digikey last month and ran into the same issue. While I was waiting for them to be shipped to me I made the cable on the left, however once I actually received the grabbers I realized it was a pain to use with the dupont connectors. So I made a new cable the same way as the first, except instead of putting the plastic housing on I just used heat shrink tubing (3/32" if I remember correctly), and it works great.

author: CustomEngineerer
author_rank: Frequent Contributor
timestamp: February 05, 2018, 02:46:31 am
content: The dreamsourcelabs people do the same thing for the cables they ship with the newer dslogic logic analyzers.

author: Kean
author_rank: Unknown
timestamp: February 05, 2018, 02:59:16 am
content: I haven't used the EZ-Hook XKM grabbers, but I bought some bulk HP and Tek grabbers on ebay over the years which work fine with the "Dupont" style single housings. These were available in large packs sold with/for logic analysers. The HP ones come in single (like EZ-Hook XKS) and dual hook versions. I think Tek only did the dual hook version, and I like their style a bit better in the way it supported the wire.The advantage of the EZ-Hooks are that you can get them in more than one colour (grey), and if you have to use heat-shrink over the crimp termination - well you can colour code those as well.
HT Multimeters teardown? - Page 1
Forum section: electronics / testgear

author: zaoka
author_rank: Frequent Contributor
timestamp: February 04, 2018, 03:59:44 am
content: Does anybody own HT multimeter, are they rebranded or custom design?This one looks interesting, nice bold digits, analog scale at the top of display...https://www.conrad.com/medias/global/ce/1000_1999/1200/1210/1219/121950_BB_00_FB.EPS_1000.jpg

author: ModemHead
author_rank: Frequent Contributor
timestamp: February 04, 2018, 04:40:53 am
content: Taiwanese manufacturer Appa Tech looks like the OEM for this model. Ideal rebadges Appa as well.Appa 98IVIdeal 61-486
Array 3710/3720 DC load firmware hacking - Page 1
Forum section: electronics / testgear

author: Malvineous
author_rank: Contributor
timestamp: February 04, 2018, 01:56:24 am
content: Hi all,I have just bought an Array 3710A DC load however I have discovered that it cannot provide a constant voltage load which is one of the reasons I bought it (the eBay listing I bought it from listed constant-voltage as one of the operating modes so I will have to lodge a dispute there but that's another story.)It got me thinking - if the unit is uC controlled, wouldn't a constant load function be implemented entirely in software? I am wondering how feasible it might be to add this function.On the Array website you candownload the firmwarefor the 372x models, but unfortunately not for the 371x models. I've e-mailed them to ask if I can get the 371x files, but I imagine I'd have to open the unit and dump the flash chip to get it. The downloaded 372x firmware is "encrypted", so I had a look at it and reverse engineered the algorithm as it was fairly obvious how they did it from looking at the patterns in the data.If anyone is interested, here is a C program that will decrypt the 372x firmware files:Code:// Compile: gcc -o decode decode.c// Run: ./decode < input.bin > output.bin#include <unistd.h>#define BLOCK_SIZE 128int main(int argc, char* argv[]){unsigned char data;int i, n;// Unencrypted headern = read(STDIN_FILENO, data, 100);write(STDOUT_FILENO, data, n);while ((n = read(STDIN_FILENO, data, BLOCK_SIZE))) {for (i = 0; i < n; i++) {data -= i + 1;}write(STDOUT_FILENO, data, n);}return 0;}The 372x firmware supports CV mode and they seem to have matching models between the 371x and 372x series (37x0A, 37x1A) so I'm wondering just how different they are internally...
NI PXI restoration  - Page 1
Forum section: electronics / testgear

author: BFX
author_rank: Frequent Contributor
timestamp: March 05, 2017, 12:34:07 pm
content: Guys I got for a good price some NI PXI stuff.NI PXI-1006, PXI-8176 embedded controller, PXI-2565, PXI-4060, PXI-2503, PXI-8422, PXI-6508, Pickering 40-110-121, Aeroflex PXI-3025 and Aeroflex PXI-3035CProblem is PXI-8176 embedded controller which is really old with only 256MB RAM and running Windows NT but it's working fine.I spent 3 days to search drivers for those two Aeroflex modules but without any result.I found PXIModuleSoftware_v8_9_0_Setup.zip athttp://ats.aeroflex.combut it's new version and doesn't work on NT.Any suggestion how to get it into running?

author: 1Ghz
author_rank: Unknown
timestamp: March 05, 2017, 02:25:40 pm
content: You can download old drivers here:RF Signal Generator (PXI-302x) VISA driver and soft front panel Version 2.3.0.0RF Digitizer (PXI-303x) VISA driver and soft front panel Version 2.1.0.0

author: BFX
author_rank: Frequent Contributor
timestamp: March 05, 2017, 09:28:27 pm
content: Quote from: 1Ghz on March 05, 2017, 02:25:40 pmThank you so much, hopefully it will work.

author: BFX
author_rank: Frequent Contributor
timestamp: March 14, 2017, 06:19:36 pm
content: Little upgrade (Aeroflex PXI-3010) but I'm still waiting for RAM and HDD.And some photos from DMM.I have plan to make photo from all modules if you are interested.

author: 1Ghz
author_rank: Unknown
timestamp: March 14, 2017, 07:25:59 pm
content: You can download PXI-3010 old driver here:RF Synthesizer (PXI-301x) VISA driver and soft front panel Version 2.1.0.0

author: BFX
author_rank: Frequent Contributor
timestamp: March 22, 2017, 07:49:12 pm
content: New HDD arrived today.Let's start fresh Win XP installation

author: BFX
author_rank: Frequent Contributor
timestamp: February 03, 2018, 05:22:28 pm
content: Finally I got time to continue to get working my PXIBut off course problems appeared.At first I tried to install Windows XP but no success with standard bootable usb key.After that I tried to upgrade the BIOS, but the same story. (see attachment)I follow NI instruction using their "Create Bootable USB KEY v1.2.1" and also copied from suggested 8176_181.zip the 512Kb files to upgrade BIOS.Current version is PhoenixBIOS 4.0 Release 6.0.6Have you guys some hints?

author: 1Ghz
author_rank: Unknown
timestamp: February 03, 2018, 07:35:05 pm
content: QuoteSource:https://www.sciencezero.org/index.php?title=How_to_create_a_bootable_USB_flash_driveQuoteSource:https://www.ni.com/pdf/manuals/370382b.pdf

author: BFX
author_rank: Frequent Contributor
timestamp: February 03, 2018, 08:12:16 pm
content: Thx for hints so far, second one is useful but not additional information's for me.
Can a PXI system replace my full desk of queipment? - Page 1
Forum section: electronics / testgear

author: 0xPIT
author_rank: Regular Contributor
timestamp: February 02, 2018, 10:58:55 am
content: Hi,over time, I've collected enough T&M equipment that I feel I could use some of the desk space it occupies...I've been thinking of replacing some of it (Rigol DS2000, 2x 6.5 digit DMMs, Signal Generator, Spectrum Analyzer, etc., not sure about Voltage Current Standard, PSUs) with a PXI system and maybe a RPi or PXI embedded controller and a 7-10" Display.I'm new to PXI. Searches on ebay reveal rather low-grade (e.g. scopes with only 100s of MS/s) equipment for rather high prices.Yet, I'd be willing to spend some 2-3k to upgrade my home lab.Can anyone with practical PXI experience share his thoughts? Is this viable at all?I'm under no circumstances starting to run Windows. How's Linux Support (GUI!)?Recommendations, comments?Thanks,- pit

author: Yansi
author_rank: Super Contributor
timestamp: February 02, 2018, 12:58:14 pm
content: It definitely can replace the price of a whole desk of equipment, thats for sure.Otherwise I dont think so. Depends on what equipment you use.

author: TheUnnamedNewbie
author_rank: Super Contributor
timestamp: February 02, 2018, 01:13:59 pm
content: Depends on the specs you need. But Keysight have entire VNAs in tiny 4-wide PXI units.The thing is that it might not be as convenient to control, and generally just more expensive. A lot of effort goes into putting that functionality in that tiny unit and it costs. And I have never found controlling a thing through a computer as convenient as doing it with buttons. We have a lot of bigger gear like VNAs and such hooked up with mouse and keyboard, but I still really prefer going in and poking the buttons.

author: Keysight DanielBogdanoff
author_rank: Unknown
timestamp: February 02, 2018, 09:02:00 pm
content: Someday, yes. Right now PXI/modular equipment tends to be much more expensive than comparable stand-alone gear. The PXI market today is definitely geared more towards manufacturing and test-rack type systems or very high end gear (10-100+ $k)If you don't need a lot of performance, your best bet is probably to go with one of the all-in-one type boxes instead of a modular system. I'd recommend looking into creative ways to maximize bench space (boom stands, etc.) instead of trying to go PXI.Linux support is also hit-or-miss.

author: thm_w
author_rank: Super Contributor
timestamp: February 02, 2018, 11:28:35 pm
content: 2-3k isn't enough to replace your current system, let alone upgrade it all.Spend the money on a better desk, see Shahriars videos for stacking ideas.
Earthy logic board for Solartron 7071 or 7081  - Page 1
Forum section: electronics / testgear

author: perdrix
author_rank: Frequent Contributor
timestamp: February 02, 2018, 03:14:18 pm
content: Hi folks,I have a 7071 with a dead earthy logic board on which I have spent more hours than I care to think about without any success. I know it is the logic board as swapping in one from another meter works just fine.Does anyone have a 7081 or 7071 that deceased for other reasons and so could part with a working logic board?Thank youDave
Extech ex845 teardown. - Page 1
Forum section: electronics / testgear

author: gearshredder
author_rank: Contributor
timestamp: January 30, 2018, 04:09:28 pm
content: I bought this thing off of ebay for $26 shipped so I thought I'd tear it down. I didn't even turn it on. Says the readings would wander. Turns out, Someone already tried fixing it, but maybe missed the two wires from the input board to the main had broke loose. You can see I re-bodged the bodge for the bad trace.I found that the teardown is pretty much the same except for the input protection and the bluetooth module. Of course I didn't get any close shots of the module lol. So I just zoomed in on what I had. I'll take some better pics if It's in demand. The bluetooth pcb has a atmega along side it. As for the rest, some caps have gone from through-hole to smd and some things moved around for space for some connectors to the bluetooth. The ICs don't have the potting material on them as they did in the ex830 teardown.https://www.eevblog.com/forum/testgear/extech-ex830-acdc-clamp-meter-teardown/I realize If I do more of these, I'll need soft lighting and something decent at macro. These were also heavily compressed jpeg. I should've captured in raw at least, to get rid of most of the blur.Top side:https://drive.google.com/open?id=129XARNH-0Gzt9OkCx3b0kOp0XypdgOUEunderside:https://drive.google.com/open?id=1RTHEIiV7rFSPZ1jfNNRqun5LHWtuTQObhttps://drive.google.com/open?id=1FEI3CQZuG4x2WQO6V22Ps69Y6yhNJHO5https://drive.google.com/open?id=1Lyj9Z17nVWOqQKN1bQMfLml1E_KUEDUThttps://drive.google.com/open?id=1u3G4ZK63C9hx32ays62Xc6EXhzctjNwfhttps://drive.google.com/open?id=1iGFB3xQRncEBNQ3E9cAggNa6lNiOPW4C

author: tooki
author_rank: Super Contributor
timestamp: January 31, 2018, 01:15:38 pm
content: Could you just upload the pix as attachments here on the forum? None of those inline images are loading.

author: gearshredder
author_rank: Contributor
timestamp: February 01, 2018, 02:18:47 am
content: hmm that's odd. It was loading yesterday lol. I'll re upload

author: retiredcaps
author_rank: Super Contributor
timestamp: February 01, 2018, 03:04:58 am
content: Wow, 6 PTCs!

author: tooki
author_rank: Super Contributor
timestamp: February 02, 2018, 02:35:07 am
content: Quote from: gearshredder on February 01, 2018, 02:18:47 amProbably because of being in your browser cache, but not available for download when the referrer page is not google itself.
Rigol DS1104 Oscilloscope and DG1022U Function Waveform Generator - Page 1
Forum section: electronics / testgear

author: Dosupi
author_rank: Newbie
timestamp: February 01, 2018, 04:20:34 am
content: Hello Everybody,I use Rigol DG1022U Function Waveform Generator to generate a sin waveform , V_pp = 1V, f = 1KHz.Then, I use Rigol DS1104 Oscilloscope to watch the sin waveform , and do FFT on DS1104.In picture 1, FFT: 20dBV 5KHz/Div 100K Sa/SAmplitude at 1KHz is -8.8dBV, 3KHz is -50dBV, the difference between them is-41.6dBV.In picture 2, FFT: 20dBV 1KHz/Div 20K Sa/SAmplitude at 1KHz is -8.8dBV, 3KHz is -46.4dBV, the difference between them is-37.6dBV.In picture 3, FFT: 20dBV 500Hz/Div 10K Sa/SAmplitude at 1KHz is -9.6dBV, 3KHz is -36.0dBV, the difference between them is-26.4dBV.In picture 3, FFT: 20dBV 500Hz/Div 10K Sa/SAmplitude at 1KHz is -9.6dBV,2KHz is -36.0dBV, the difference between them is-31.2dBV.I don't know What's wrong with my test? and which data is correct

author: Neganur
author_rank: Unknown
timestamp: February 01, 2018, 06:00:02 pm
content: What is it that you’re trying to measure?-8.8dBV is around 1Vpp so the first picture looks correct.The yellow sine wave in picture 2 and beyond looks distorted, try to increase the time/div without decreasing the sample rate (10ms/div is down to 50MSa/s ? Does the scope have more than 7.5Mpts of memory?)EDIT: I saw the spec sheet mention that the sample rate is shared by all channels. Disable all except for the one you’re using to maximize the sample rate (1GSa/s * 12 div * 1ms = 12Mpts memory)
Anritsu MS2661A/B/C/N - Page 1
Forum section: electronics / testgear

author: Gustavo
author_rank: Contributor
timestamp: December 27, 2017, 03:35:54 am
content: Hi friends, recently I got an Anritsu MS2661N Spectrum Analyzer from Ebay. The unit is working wonderful but I want to have the Service Manual just in case something happens. The A/B/C/N 2661 versions are almost the same with some minor wardware/firmware differences.Please help me to find the SM !Thanks in advance.Gustavo

author: ccktek
author_rank: Regular Contributor
timestamp: January 31, 2018, 10:26:11 pm
content: Hi Gustavo,I too have an MS2661N, mine not working. I'm wondering if you ever found a service manual.Thanks,CCKTEK
Hacking/reverse engineering the Instek GDS-2000E - Page 1
Forum section: electronics / testgear

author: rhb
author_rank: Super Contributor
timestamp: January 29, 2018, 11:32:31 pm
content: I am engaged in hacking the GDS-2000E line. I have a 2072E specifically purchased as a target and an MSO-2204EA to do the work.I am NOT interested in cracking license codes. My goal is to be allow the user to custom program the instruments and to perform calibrations if suitably equipped.The 2000E is an FPGA dev board with some additional features. So reprogramming should not be all that hard.A brief examination shows an ADC, a couple of FPGAs, 256 MB of SDRAM, 128 KB of flash, input attenuators, etc in the 2072E. The 2204EA has a lot more stuff in the box. Both run the same FW.The first step is to generate basic system and service data. From what I've seen that's not too hard to do from a photograph with detailed checking as needed at key points . DIY "Sam's Photofacts". Just for fun one could take the topology, feed it into a simulator and calculate the optimal values for the passives using FEM analysis of the PCB.Basic goal:A buildable Instek/Xilinx Linux system with user ability to reconfigure menus and execute SCPI command scriptsMixture of open and closed source FW, but with APIs fully documented so that independent implementations are possible.Ability to reload factory FW at any time.Once one has a reasonably accurate block diagram and has identified the blocks on the PCB, it is fairly easy to select test points for detailed documentation needed for component level trouble shooting. And the device behavior severely limits the number of possible solutions..One nice aspect is that if everything is kept at VHDL level, the system should be pretty portable and thus a way to update old kit for custom uses.I also plan to get a Zynq based dev board. Current favorite is the Zybo V7 - Z20If anyone has an interest in developing a way to make self maintenance easier and cheaper I'd like to ask you to join in this effort.'ll append a PDF with what I know so far later.

author: rhb
author_rank: Super Contributor
timestamp: January 31, 2018, 09:35:36 pm
content: It's very striking how repairable at component level these things are. Everything is just a general purpose FPGA dev board with a few extra bits added. So just knowing the major parts gives much of the structure.0.1"headers:J500 1x6 (unpop on 2204)J501 1x5 (unpop on both)J502 2x5J1170 1x6 (unpop on 2204)Does anyone know anything about these? J501 looks as if it's a JTAG used for factory programming. J502 has lots of traffic, but I haven't identified the bus types yet.Flash:S34ML01g100TF100 1 GibSDRAM:Dual H5PS1G63JFR S6C (256MB total)FPGA 2:Spartan 6 XC6SLX4 (apparently LCD and panel controls)
Tek 465b - Transistor Position on Board - Page 1
Forum section: electronics / testgear

author: pushpin
author_rank: Newbie
timestamp: January 31, 2018, 08:10:37 pm
content: Found a scan. The Fet is in the correct position - lug pointing downwards.Tektronix 465bWhen repairing the Ch.1 Var control - case off, power off - I accidentally knocked a transistor out of it's base. Stupid idiot I hear you say. The board is 670-5998, the Vertical Mode Switch.I think it might be a FET rather than tr. So the lug would be Source.So. Does the emitter/source of the transistor/FET (the lug) point to the bottom, or have I got it the wrong way round?I'd be so grateful if a forum member would point me in the right direction for this error on my part. Although I have the service manual, I don't have scan of this board.CheersAl
Would someone be able to scan a couple pages from the HP 8601A manual? - Page 1
Forum section: electronics / testgear

author: TimInCanada
author_rank: Regular Contributor
timestamp: January 31, 2018, 01:21:11 am
content: BothBAMAandKO4BBhave copies of the operating and service manual scanned by VK5ZLR. Generally an excellent scan except for two pages, 8-25 and 8-27 where the schematics had scope traces for test points, e.g.,:If someone has an original service manual, would it be possible to get those two pages scanned into images that show the scope traces? It will be much appreciated!Tim

author: TerraHertz
author_rank: Super Contributor
timestamp: January 31, 2018, 06:53:08 am
content: Coming up. Maybe tonight, maybe tomorrow. Depends on other stuff I have planned.Scan, stitch & adjust take a bit of time.Edit: here you go. Four files, total doesn't quite fit in 2MB max-per-post, so 2 in next post.

author: TerraHertz
author_rank: Super Contributor
timestamp: January 31, 2018, 12:02:35 pm
content: The other 2.

author: TimInCanada
author_rank: Regular Contributor
timestamp: January 31, 2018, 06:18:19 pm
content: Ah, so that's what the traces are supposed to look like.Thanks very much TerraHertz. Great stuff.Tim