hybridfree/eevblog-posts huggingface dataset:
TDS310 schematic - Page 1
Forum section: electronics / testgear

author: xchip
author_rank: Regular Contributor
timestamp: July 25, 2014, 09:59:19 pm
content: Hi,I recently bought a TDS310 oscilloscope, I'd like to hack the firmware and also add a serial port to it.Does anyone have the schematics?Cheers!xchip

author: dfmischler
author_rank: Frequent Contributor
timestamp: July 25, 2014, 10:23:58 pm
content: The service manual for that scope does not have any schematics in it. I'm sure they exist somewhere, but Tektronix did not support field maintenance of that scope to the component level.IIRC, there was a communications card you could plug into that scope. The "option 14" gave you GPIB, RS232, and perhaps a Centronics parallel interface. The module was also apparently referred to as TD3F14A.

author: xchip
author_rank: Regular Contributor
timestamp: July 26, 2014, 01:02:19 pm
content: Yeah I saw the option 14 thing, but I would like to build my own and emulate it using an Arduino.I wonder if I could dump the firmware using a JTAG... Does anyone want to join this venture? :-)Cheers!

author: edavid
author_rank: Super Contributor
timestamp: July 26, 2014, 04:14:41 pm
content: The closest you can get is the "TDS340A, TDS360, & TDS380 Technical Reference", 070-9436-04. It does have schematics, but not for your exact model. PDF is available from tek.com and several other places.

author: alex.forencich
author_rank: Frequent Contributor
timestamp: July 26, 2014, 08:43:48 pm
content: Quote from: xchip on July 26, 2014, 01:02:19 pmAn EPROM programmer would be more likely for an instrument of that era as they generally have a set of firmware EPROMs instead of on-board flash.

author: nctnico
author_rank: Super Contributor
timestamp: July 27, 2014, 08:41:10 am
content: The rear of a TDS310 look suspiciously similar to standard PC slots. Maybe adding a standard PC serial interface (ISA slot) does the trick to add a serial port. Forget about emulating with an Arduino. You need a memory bus interface and even the good old ISA works at 8MHz.

author: xchip
author_rank: Regular Contributor
timestamp: July 27, 2014, 12:33:23 pm
content: Quote from: edavid on July 26, 2014, 04:14:41 pmExcellent!!!, this was of great help, it shows the oscilloscope is using an MC68331 processor running at 15.15Mhz.Some thoughts after looking at the pdf:- The flash memory for the firmware is 256Kb x 3 = 768Kb... That's a lot!!- The option board comes with a 256k EPROM... Isn't too much?- Another way to hack the oscilloscope is to tap onto the timebase module.- At some point is says "Increase the frequency of the generator output to 100 MHz (TDS 340),200 MHz (TDS 360), or 400 MHz (TDS 380)."- Sice this schematic is valid for all 3 oscillsocipes, does that mean that the TDS340, the TDS360 and 380 use them all the same hardware? Then with a SW hack you could convert a 100 Mhz into a 400Mhz right?Cheers
787 out of spec or not? - Page 1
Forum section: electronics / testgear

author: daddario
author_rank: Regular Contributor
timestamp: July 27, 2014, 11:17:36 am
content: Hi!I'm having some confusion with the current source on my Fluke 787, which outputs a bit of garbage on the lower settings.I've never hereinbefore been bothered by it as I really haven't used it with such small currents, but now I just wanted to finally clear things up, mostly for myself.The error is pretty much the same for source and simulate outputs. Both the user-, and cal. manual state "Accuracy: 0.05 % of span".Does that mean 0.05% accuracy of 20mA or 0.05% of the programmed value?I did some measurements and this is the result:The left number is the programmed value on the 787 and on the right, the value read from another DMM, rounded to a 100nA.400uA 401,4uA300uA 301,9uA200uA 200,9uA100uA 97,7uA50uA 46,1uA40uA 36,0uA30uA 25,4uA20uA 15,2uA10uA 4,7uAAbove that it's pretty much spot-on.If the accuracy is for the whole 20mA span, then a 10uA error is permissible at all times and everything is more than fine. But if not...
Power Designs 2020B - Page 1
Forum section: electronics / testgear

author: v1t0r
author_rank: Contributor
timestamp: July 25, 2014, 06:40:38 pm
content: Recently I got a Power Designs 2020B, converted to 230v by changing the connections on the transformer, but when I try to calibrate it to zero volts it does not falls below 110mV. Any idea on what could be wrong.ThanksVitor

author: saturation
author_rank: Super Contributor
timestamp: July 25, 2014, 10:41:44 pm
content: A common problem is dirty and less likely, faulty, fine adjustment potentiometer, this is the 10 turn pot underneath the main dials. Cleaning it can't hurt and see what happens. Use a very high quality metrology grade contact cleaner, in the USA we use Dexoit.P.S. To help the diagnosis turn the pot clock and counterclockwise, the output voltage should rise and fall in step. If it jumps around or doesn't rise or fall in step, its more likely the cause.
DP832 problem - Page 1
Forum section: electronics / testgear

author: skench
author_rank: Contributor
timestamp: July 24, 2014, 11:36:46 am
content: I received a brand new DP832 power supply from Telonic Instruments (UK) on Tuesday and like others on this forum after a quick check I added the required keys to upgrade the unit.It came with:Digital version 00.01.10.00.03Analogue version 01.02.02Boot version 01.09Then I noticed that channels 2 and 3 were not working properly but I could not remember if had been working before I had added the keys. Both channels showed UR instead of CV or CC.I checked with Telonic and they agreed it was faulty and even offered to doa next day swap-out but in all honesty and with no way of removing the keys I could not take them up on their offer.So I had to find the fault and fix it my-self. I new the problem had to be on the bottom board so I opened up the unit and did some probing with my trusty multimeter. They PCB is nicely marked with a load of test points and I soon found that the -15 volt supply was missing so I had to remove the bottom board to track the problem down.It turned out that one of the legs of the -15 volt regulator had been poorly soldered, all other joints looked perfect so a quick touch-up with the iron soon shorted that out.After carefully reassembling all channels work perfectly and I am a happy bunny.The morale of this tale is to leave your new equipment a few days or even weeks before installing any updates!

author: Sebastian
author_rank: Regular Contributor
timestamp: July 24, 2014, 01:19:07 pm
content: You can remove the options with a computer! Connect to it via Ultra Sigma and type " :SYSTem:OPTion:UNINSTall " (without "") .
Universal power source - made in Belarus teardown - Page 1
Forum section: electronics / testgear

author: WackyGerman
author_rank: Regular Contributor
timestamp: July 25, 2014, 08:11:38 pm
content: Here are the teardown pictures of my old universal power source , made in Belarus . It looks really old and crusty but this bastard is still in good working condition .

author: WackyGerman
author_rank: Regular Contributor
timestamp: July 25, 2014, 08:15:07 pm
content: and the documentation with the schematic of this old puppy
Rigol DP832 Crappy Python GUI - Page 1
Forum section: electronics / testgear

author: coflynn
author_rank: Regular Contributor
timestamp: July 24, 2014, 08:29:09 pm
content: I made a (very) crappy Python GUI that interfaces to the DP832. Basically I wanted something to graph current in real-time for monitoring power consumption as switching through different areas of a microcontroller (checking that certain things are switching off mainly). It seemed the graphing application on the DP832 had fixed 3A axis, so I wasn't able to zoom in, although perhaps I'm missing the settings. Anyway this doesn't implement a real class for talking to the DP832 as I only use a single command, so it doesn't use the Python-IVI framework.The code is posted athttps://github.com/colinoflynn/dp832-gui. The GUI looks something like this, here I'm plotting power during a Raspberry Pi boot cycle:There's a video of it running but it's 100% as exciting as you would expect a video showing a simple graphing application to be:

author: Slappy_g
author_rank: Regular Contributor
timestamp: July 24, 2014, 11:45:51 pm
content: Pretty cool little app!Actually, I thought the video was a handy walkthrough to see what the app can do. As a suggestion, next time have some dramatic opera music in the background...

author: bwat
author_rank: Frequent Contributor
timestamp: July 25, 2014, 11:27:19 am
content: Your software is a direct reflection of your thinking. I had a quick look at your code and I don't know enough Python (I know nothing about the language to be honest) to say too much but your code looks like it was structured in accordance to a reasonably well thought out design. I wouldn't call your code "crappy" so you really shouldn't be calling your software "crappy" either.It sounds like you needed a tool to get a simple one-off job done, and, it looks like that's what happened. That's a success in my book. The fact it's not a monster program doing all manner of useful things is testimony to your understanding of the importance of parsimony in design. The fact it crashes when you do things in the wrong order (as described in your comments in the code), well it's a one off and if you need reliability you can spend some time fixing it.I think you're being too hard on yourself.

author: coflynn
author_rank: Regular Contributor
timestamp: July 25, 2014, 04:54:05 pm
content: Thanks for the kind words! Although I only called it 'crappy' because I don't want people to think it will later get extended to a full-on GUI or anything, it's solely a real-time display app ;-) So maybe 'simple real-time display app' is a better description, but anyway it does what I needed...Anyway hopefully somebody finds it useful, if you have trouble getting it to run let me know!
DS2000A patched firmware file?  - Page 1
Forum section: electronics / testgear

author: Neddie
author_rank: Contributor
timestamp: July 24, 2014, 07:06:45 am
content: Hi all.Anybody geniuses out there working on making a patched firmware file out of the latest DS2000A firmware release.The patched version that is currently available is 00.02.01 , current firmware is 00.03.00.01.03.Looking for something that can be used with the upgrade utility software.CheersNeddie
Agilent U8032A mini-teardown - Page 1
Forum section: electronics / testgear

author: simingx
author_rank: Contributor
timestamp: July 24, 2014, 10:34:22 am
content: Don't turn it on, take it apart!The U8032A is one of Agilent's "low-cost" offerings, it's a 375W triple-output supply (0-60V, 0-3A x2 and 5V 3A).http://www.home.agilent.com/en/pd-2054589-pn-U8032A/triple-output-dc-power-supply-60v-3a-2x-375wIt's able to do basic output sequencing by switching between 3 memory outputs, although an E36xx it isn't.Surprisingly, it's a switch mode design. It is rather heavy though, at almost 9kg's.Didn't go into too much detail, the internal boards are not easily taken apart, and it isn't exactly mineSorry for the poor images, I used my mobile phone for them...Front panelRear panel with large 120mm fan. Yes it's a bit noisy, as you'd expect.Chemi-Con KX main filter capacitorsMains filter and wiringMain bridge rectifier and some TO-220 devices (preregulation?)Small toroid for auxiliary supplies. I thought it might be the main transformer, but that doesn't look like it can supply 375W to me...STM32 micro for front panelMain PWM control chip5V output control sectionTop side of 5V output. You can see the capacitor hanging off the output 2 jacks... afterthought?Primary side of one of the main 60V 3A output boards. Secondary side is obscured by filter components, and I wasn't going to disassemble the unit further...Control section for main outputs. That's quite a lot of horsepower (AT91SAM7X128)!Pretty LCD panelThat's all for now, if you guys want anything more let me know and I'll try to get a picture if I can access it.
Hioki Analog Meter - Page 1
Forum section: electronics / testgear

author: simpson
author_rank: Contributor
timestamp: July 23, 2014, 02:44:24 am
content: Just got this Hioki AS-500F analog meter from eBay for under $15 shipped. It stands about 7" tall.It looks great and works fine. It boasts 30k ohms/volt DC sensitivity & 10K on AC. Other specs and date of mfr are unknown. I especially like the push buttons in place of the usual rotary switch.This is my first Hioki product. I know they make some very high end test gear. This one seems well made though not as heavy duty as the big Simpsons or Tripletts.Anyway, it seems like a real bargain and I'm happy with it.

author: zaoka
author_rank: Frequent Contributor
timestamp: July 23, 2014, 03:22:03 am
content: This is their best analog multimeter from 196x:https://www.eevblog.com/forum/reviews/hioki-analog-multimeter-m-230a-need-help-with-restoration-resistor-values/

author: radhaz
author_rank: Regular Contributor
timestamp: July 23, 2014, 06:04:15 am
content: Very nice looking VOM. If you feel like taking the case off, let us see the innards~.

author: simpson
author_rank: Contributor
timestamp: July 23, 2014, 04:34:05 pm
content: Here's some pix:
HP972A multimeter - Page 1
Forum section: electronics / testgear

author: najrao
author_rank: Regular Contributor
timestamp: July 23, 2014, 11:11:19 am
content: Because of file size limitation, I have replaced photos with new, and perhaps more relevant ones.I have this beautiful instrument in pristine unmolested condition, but alas, with a serious fatal fault. I am hoping friends here can help.Basically, though marketed by HP, the 972A is made by Yokogawa in Japan; I can tell because its case and, indeed most contents, are the same as another of mine, Yokogawa 7544-02. The specs and features are different, however.Inserting the two AA cells into the perfectly clean battery holder -- simply turns on the entire display with an initial beep. The buttons, including the power on, or even the rotary switch, have no effect at all. The all-characters display, presumably during some kind of POST going on, just refuses to yield to anything else. The auto-power-off function did not do so in half an hour.Being sealed at case, it needed but little cleaning inside; this I have still done, by a dry brush, all around the two main chips; have restricted the use of isopropyl alcohol to the zebra stripe connector area because the selectively applied conformal coating seems to give.I have tried the drying out and ionizer discharge techniques, to no avail. Not having any manual, I am next driven to 'locating a sweet spot' technique.Alas, there is no Reset button, or I don't know where to look.HP/Agilent and Yokogawa do not seem to offer any service manual for this elderly product; the user manual has a few lines of trouble-shooting, with zero helpfulness.Yoko do not identify this model in their website, not even in the archives/obsolete products area; perhaps, they made it to a HP spec, and did not release with their own logo.To say I would be grateful for help, any help, would be understating my position; I would give my eye teeth or unto half my kingdom according to choice.Thank you, my friends.NAJR.

author: lowimpedance
author_rank: Super Contributor
timestamp: July 23, 2014, 11:34:03 am
content: Perhaps some good pictures of the PCB's showing part numbers of the main IC's around the display etc (I assume there are no chip under blobs here!!).
Rigol DP832 Question (analog/digital power from same PSU) - Page 1
Forum section: electronics / testgear

author: staze
author_rank: Frequent Contributor
timestamp: July 22, 2014, 06:46:36 pm
content: All,Thinking about picking on of these Rigol DP832 up, and have a question. Since channel 2 and 3 share a common connection, it seems like the DP832 would not be able to be used to power both the analog and digital side of board in that, I couldn't track with channel 1/2 ±15V, then give 5V to the digital side of things with channel 3, correct? I'd have to run channel 3 to a 5V regulator with, at the lowest, 10V?Basically, could I get away with having just one bench power supply. =PThanks!

author: MarcelM
author_rank: Contributor
timestamp: July 22, 2014, 07:09:49 pm
content: You can, assuming that you use output 1 for the negative supply, and output 2 for the positive.Connect the plus side of output 1 to the shared ground of output 2 and 3.Then you'll end up with -15V, +15V and +5V, which is what I assume you're looking for.Rgds,Marcel

author: staze
author_rank: Frequent Contributor
timestamp: July 22, 2014, 09:29:22 pm
content: Quote from: MarcelM on July 22, 2014, 07:09:49 pmOkay... weird. I thought for some reason output 3 could only be at most, 5V different than output two, since they share a ground. So then theoretically, I could also do -30V, +30V, and +5V?

author: MarcelM
author_rank: Contributor
timestamp: July 22, 2014, 09:48:37 pm
content: Quote from: staze on July 22, 2014, 09:29:22 pmNot just theoretically, you can even do that in practiceYou could also do +60V and +5V, or +30V@6A and +5VUseful little power supply....Marcel

author: staze
author_rank: Frequent Contributor
timestamp: July 22, 2014, 09:51:17 pm
content: Quote from: MarcelM on July 22, 2014, 09:48:37 pmOkay then. =) So, what problems do youactuallyface with regards to the shared common for Channels 2 and 3?

author: MarcelM
author_rank: Contributor
timestamp: July 23, 2014, 08:31:37 am
content: Quote from: staze on July 22, 2014, 09:51:17 pmThe only issue I can think of, is the way Rigol does current sensing in the (shared) ground connection. EEVBLOG's Dave did a video on this. Best solution is to have a solid ground connection between the ground terminals of output 2 and output 3.Other than that, the power supply has been performing nicely for me...Regards,Marcel

author: TomThomas
author_rank: Contributor
timestamp: July 23, 2014, 09:41:10 am
content: Quote from: staze on July 22, 2014, 09:29:22 pmHi,if you Need +30 V and -30V and +5V, why you don't go directly for a DP831??br Tom
FLIR ONE any news? - Page 1
Forum section: electronics / testgear

author: Jay_Diddy_B
author_rank: Super Contributor
timestamp: July 01, 2014, 02:10:31 am
content: Hi,Flir issued a press release in January 7th. 2014 with a worldwide roll-out for late spring 2014. This is a thermal imaging adapter for a smart phone. They don't mention if the device is a thermometer or if it is an imager.http://www.flir.com/flirone/press/asset/Discover/FLIR%20ONE_Launch%20Release_FINAL.pdfHas anybody heard the release date?Did anybody sign up to reserve one?Regards,Jay_Diddy_B

author: ixfd64
author_rank: Frequent Contributor
timestamp: July 01, 2014, 02:21:49 am
content: They're due to come out at the end of July:http://blogs.wsj.com/personal-technology/2014/06/12/flirone-infrared-iphone-camera-available-in-late-july

author: KK
author_rank: Regular Contributor
timestamp: July 01, 2014, 02:59:51 am
content: $349 is an interesting price point...

author: Iphone_hack
author_rank: Contributor
timestamp: July 01, 2014, 06:30:07 am
content: Well it is kind of late for flir one for iPhone 5 and 5siPhone 6 is coming out soonIf buying the flir one, it will mean that it will need to keep the iPhone 5 or 5sEven I think flir one it will be more of a toy than toolI was waiting since flir showed last year.But I end up buying 2 E4 in MayWhile it was still hackable.

author: ICGEngineerTech
author_rank: Newbie
timestamp: July 03, 2014, 06:51:10 pm
content: Quote from: Iphone_hack on July 01, 2014, 06:30:07 amI have to agree with you to a point. The fact that it's over $300 I'd have to say it'd be an expensive toy. However, to use this as a tool to gather empirical data for a engineered item that is being tested for something like an aircraft (DO-160 and such) I don't think it could be used. Our FLIR camera is sent of once a year to get it's official CAL. The items used to calibrate the camera, mainly blackbodies, are also calibrated (really just measured) and tracked. I doubt this will ever be used in any kind of official capacity. But certain a cheep way to get that warm and fuzzy that your product is preforming thermally the way it was designed before heading off an official lab for score.Still, I'm going to try and have our ENG department snag one of these up to put on our lab iPhone we use for testing communications with our products <router, SATCOM computer, etc.>

author: smoothtalker
author_rank: Regular Contributor
timestamp: July 22, 2014, 03:08:22 pm
content: The wait is over! pre order begins tomorrow! anyone getting it?http://flir.com/flirone/index.cfm
Hioki has a new contactless VOLTAGE clamp on a Power Logger - Page 1
Forum section: electronics / testgear

author: CosPhi
author_rank: Regular Contributor
timestamp: July 22, 2014, 08:38:54 pm
content: They can measure the voltage without even when the wires are insulated. They use the insulation as an capacitor and generate a voltage in the clamp. When the generated voltage is the same as in wire no current flows in the "capacitor" and the generated voltage is now the voltage to read.I think that's really a great thing. These days everything is so well insulated, so it is often difficult to get a good contact with the crocodile clams on the screw.On the image below you can see the principal.Japanese company's invent great things and nobody knows ... they have to yell MUCH LOUDER ...http://www.electrotest.co.nz/PDF/PW3365E1_46E.pdf

author: CosPhi
author_rank: Regular Contributor
timestamp: July 22, 2014, 09:22:07 pm
content: It seems they have an electrical tester with this technology too. The SAFETY HiTESTER 3258 with a design straight out of the early 80s ...http://www.hioki.com/products/dmm_insulation_clamp/dmm/186Does somebody have any experience with it? Even I don't like the contactless pen style voltage detector, this does looks interesting to me.Uhh ... I just saw the price somewhere ...
Curious Fluke 8846A Behavior (bug?) - Page 1
Forum section: electronics / testgear

author: kwass
author_rank: Frequent Contributor
timestamp: July 22, 2014, 01:52:27 am
content: I was setting up to use the rear terminals on my Fluke 8846A and saw something buggy.When I put it in the capacitance mode, rear terminals selected with no leads plugged in, it read a few pf of negative capacitance. Once I plugged in leads, all was fine and I got accurate results. I've never seen negative capacitance numbers using the front terminals.FYI: OutG=2.31.926.24, InG=ad300220As Bob Pease would have said, "What's All This Negative Capacitance Stuff"?
Calibration for HP 8901B Modulation analyzer - Page 1
Forum section: electronics / testgear

author: MattSR
author_rank: Regular Contributor
timestamp: July 12, 2014, 12:10:56 am
content: Hi Guys,I recently purchased a lovely new (old) HP 8901B analyzer. From the bloke I bought it off, I know it was last calibrated 5 years ago, however I would like to get it done again. Does anyone know of any places to get it calibrated in Sydney, Australia? I did receive a quote from one place and they wanted $2,000 for it to be certified to NATA standards (whatever NATA is..)Cheers,Matt

author: MattSR
author_rank: Regular Contributor
timestamp: July 19, 2014, 12:10:42 am
content: Bump... Anybody? Surely someone in here knows of a place to get test equipment calibrated in Sydney..

author: TheRuler8510
author_rank: Regular Contributor
timestamp: July 19, 2014, 01:21:27 am
content: Ouch!...I got a perfectly good working unit off eBay last year for only $100, so it seems crazy to pay $2000 for a cal.Why do you need it to be so precise? ...just curious.

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: July 19, 2014, 08:10:21 pm
content: Did you see the Operation and Calibration Manual?http://cp.literature.agilent.com/litweb/pdf/08901-90113.pdf.Brief look at the document tells me that most of function have self-calibration built in so you just need to follow the steps described. Also if you have RF signal generator and RF power sensor you can probably use that, I did not find references to any tools in a document however.

author: edavid
author_rank: Super Contributor
timestamp: July 20, 2014, 06:45:19 pm
content: This is not a precision instrument, or a valuable one, and 5 years is not very long ago, and most cal labs are not going to be at all familiar with it. Summary: Don't do it!

author: MattSR
author_rank: Regular Contributor
timestamp: July 22, 2014, 08:54:59 am
content: Hi Guys,Awesome responses, thanks for the help. I somehow missed the calibration manual which looks very handy. I have access to an up to date Aeroflex 3920 that gets an annual calibration done, so I will just use that to check the 8901B.TheRuler - I can't believe you got one for $100 - wow!!! I'm using it to align and calibrate some digital radio equipment (APCO P25) and also to develop an open source version even further (using GNUradio and a USRP) I guess its not worth the cost and the DIY cal will be more than good enough.edavid - That makes perfect sense, since I have the gear and now the manual to calibrate it myself, that should be more than good enough!Thanks for the responses!Cheers,Matt
Hantek DSO1062B screen flickering - Page 1
Forum section: electronics / testgear

author: strtfr
author_rank: Newbie
timestamp: July 21, 2014, 06:01:29 pm
content: Hi,A few days ago I received aHantek DSO1062Bhandheld device. Immediately after power up I noticed display flickering on the horizontal display lines. It is worse during bootup and momentarily halts when the display shortly locks. I have used auto calibration, changed display colours, changed display refresh rate, disconnect charger, let it warm up, check for software updates, but nothing solves the problem.In the worst case I have to send it back. But to be honest this is something I would like to avoid. Although the seller has yet to respond, I would like to inform if someone already has some experience with this issue. It seems that the screen is picking up some interference, probably from the scope itself. Besides this screen problem, that is really a bad thing.Any pointers?It's actually a decision between opening up or sending it back, so ..Thanks
HP35660A DSA Calibration Time? - Page 1
Forum section: electronics / testgear

author: geo_leeman
author_rank: Regular Contributor
timestamp: July 31, 2014, 08:15:28 pm
content: Hey all,I was able to score a HP35660A recently, which is great considering I work with seismic equipment! I haven't ever owned/used one of these before, but couldn't pass the opportunity. I bought it "As-Is" and have been perusing the manuals. My question is how long should the "Calibration in Progress" take? The unit boots up, passes all of its self-tests and the failure log is clean, but that message will stay up. I've let it run over an hour or two with no change. If you mess around in the menu system, eventually it will just stop responding and require rebooting. Maybe this is going to turn into a repair.
Keithley 775A. Any thoughts? - Page 1
Forum section: electronics / testgear

author: ElektroQuark
author_rank: Unknown
timestamp: April 23, 2014, 01:54:19 pm
content: Hi,eBay, free time, ... you know. A Keithley 775A counter is traveling here now.Manuals are available online (thank you Keithley) but there is no more information about it.Anyone want to share experiences or opinions with/about it?

author: edavid
author_rank: Super Contributor
timestamp: April 23, 2014, 03:39:50 pm
content: Quote from: EdoNork on April 23, 2014, 01:54:19 pmI have one, and I like it a lot. It seems to trigger a little better than an HP 5315/5316. The front panel buttons don't have a very nice feel, but they have been reliable so far.If it didn't come with the C channel, you can add one pretty easily.

author: idpromnut
author_rank: Unknown
timestamp: April 24, 2014, 11:29:57 am
content: Erk, yes, I am curious how nice this counter is… I have my eye on a 776...

author: ElektroQuark
author_rank: Unknown
timestamp: April 24, 2014, 02:55:40 pm
content: It has the C channel and TCXO options.It will arrive in some days.

author: rastro
author_rank: Frequent Contributor
timestamp: July 20, 2014, 12:49:04 pm
content: I think these Keithley 77X are OEM from a company called TABOR.775 ~ Tabor 6020776 ~ Tabor 6030The Tabor also posts manuals (poorly legible schematics as the Keithley manuals).
Elavi 5 Multimeter - Page 1
Forum section: electronics / testgear

author: Simon123
author_rank: Regular Contributor
timestamp: July 20, 2014, 12:59:56 pm
content: Hello!I have this multimeter, but the readings are low and at resistance measurment the scalle cannot reach 0 though battery has 1.5VDoes anywhone have schematic for it or anything else that would help?Thanks

author: Simon123
author_rank: Regular Contributor
timestamp: July 20, 2014, 05:45:23 pm
content: Looks like movement is bad.Meter suplies 250uA at full scale, but movement takes 400uA for full scale.Is there any way of repairing it?

author: radhaz
author_rank: Regular Contributor
timestamp: July 21, 2014, 01:35:53 am
content: It appears to still be in production:http://www.alte-messtechnik.de/hub/analog/multimeter/elavi/elavi-5.htm

author: Simon123
author_rank: Regular Contributor
timestamp: July 21, 2014, 12:19:28 pm
content: Thanks, i now at least have some specs, thoug cant find anything pointing that is in production.I forgot to mention that some resistor on voltage divider wasnt connected-unsoldered and i cant see any diode protection(its shown on scale) on meter except diodes for AC.
What is a PBX simulator good for? - Page 1
Forum section: electronics / testgear

author: gooseEL34
author_rank: Regular Contributor
timestamp: July 21, 2014, 07:45:00 am
content: Got a lot of parts (I like metal enclosures and build guitar effects into them after gutting).Got a Micro Seven LS100 Mini-PBX Simulator.Any idea what this does....a google search got me to the Micro Seven webpage, but it went over my head?I am assuming some kind of telephone line quality tester....No knobs. Essentially a power cord and 2 telephone jacks on the back with one red led (on hold/busy) and one trimpot (line level) on each....Reading the site, I "think" you plug a phone into it and by punching in phone numbers and pound sign codes, you can get various responses.Interesting?

author: nctnico
author_rank: Super Contributor
timestamp: July 21, 2014, 08:44:20 am
content: It is a public exchange simulator. Probably to make phone calls between two devices without having to pay phone costs.
Waveform templates for scope reviews - Page 1
Forum section: electronics / testgear

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: July 18, 2014, 06:54:31 pm
content: Hi All!I got two 'new' scopes and am preparing to do reviews of them. The only limitation is that my primary signal source is still a Siglent SDG1020 20MHz AWG (didn't find time yet to expand my home lab).However, often enough people are looking for specific tests that the reviewer doesn't think of when doing the review. So aside from a demonstration of functionality and the obligatory waveform/s tests, is there anything else you would like to see in a review?I also thought that if someone is looking for a specific test (i.e. glitch capturing with a specific signal) then he could provide the signal as waveform template (.csv format) which I can upload to my Signet SDG1020 and do the test with. Those with newer Siglent scopes (i.e. SDS1000CNL/CML) can also just capture a waveform and save it as data file for Siglent AWGs.Thinking further, if we collected these files we could build a standardized set of tests for review, which could make it easier to compare basic performance parameters of different scopes.Any comments/ideas/rants?

author: David Hess
author_rank: Super Contributor
timestamp: July 19, 2014, 11:31:49 pm
content: The two tests that I like to do involve high speed pulses which your 20 MHz AWG is not going to handle at all.I would test for glitch response at slow horizontal speeds with pulses below 100 nanoseconds using both the minimum and maximum record lengths. An old 2230 for instance can catch a 100 nanosecond pulse 100% of the time at any sweep speed. An old 2232 does the same with a 10 nanosecond pulse. More modern DSOs should only be limited by their vertical bandwidth but some fail spectacularly.The other test I like to do is to check for aliasing on fast edges which will reveal non-linearity and jitter in the digitizer. Modern real time oscilloscopes seem to be more susceptible to this than old equivalent time oscilloscopes because their real time sampling rates are relatively low. Aliasing is revealed by "wobbulation" in the sin(x)/x reconstruction. This test may also be done with a fast sine wave source operating at close to the oscilloscope's rated vertical bandwidth independent of the current Nyquist bandwidth.
Panasonic Digital Storage Oscilloscope VP-5730P - Page 1
Forum section: electronics / testgear

author: Axtman
author_rank: Regular Contributor
timestamp: February 18, 2014, 05:27:40 am
content: Does anyone know anything about the Panasonic Digital Storage Oscilloscope VP-5730P? A guy is offering one for sale for under $100. My only concern is not finding a manual online. Thanks!

author: EEVblog
author_rank: Unknown
timestamp: February 18, 2014, 07:00:58 am
content: Google brings up this thread :->That looks like an old beast, can't have much digital spec, I'd spend the money on a pure analog instead.

author: Hydrawerk
author_rank: Super Contributor
timestamp: February 18, 2014, 10:49:26 am
content: It must be a rare scope...

author: Hydrawerk
author_rank: Super Contributor
timestamp: July 19, 2014, 03:04:21 pm
content: Does anybody have any info on Panasonic VP5720A digital oscilloscope? Is it from early 1990s? It does not look like a rebadged product...
BK Precision 2530B Any Good? - Page 1
Forum section: electronics / testgear

author: polishdude20
author_rank: Contributor
timestamp: July 18, 2014, 02:15:13 am
content: I've got a chance to get the BK Precision 2530B for $150 and I was wondering if it's a good scope for a beginner? Is $150 a good deal for it?

author: elliott
author_rank: Regular Contributor
timestamp: July 18, 2014, 03:48:49 am
content: It is a rebranded Atten scope, I believe it is an ADS1022C. The main complaints I've heard from the Attens is firmware.Dave had a poke around at the Siglent branded version the SDS1022C.

author: polishdude20
author_rank: Contributor
timestamp: July 18, 2014, 05:48:18 pm
content: Would it still be better than a 5mhz Digilent Analog Discovery?

author: elliott
author_rank: Regular Contributor
timestamp: July 18, 2014, 08:40:27 pm
content: As an oscillocope? Sure, but the Digilent is a multi-tool.

author: polishdude20
author_rank: Contributor
timestamp: July 18, 2014, 09:30:07 pm
content: Quote from: elliott on July 18, 2014, 08:40:27 pmYeah I was thinking the digilent would be a cheaper option considering it has many other functions.
Low-voltage, low-current continuity tester - Page 1
Forum section: electronics / testgear

author: gdewitte
author_rank: Unknown
timestamp: March 23, 2014, 05:42:54 pm
content: Many years ago (sometime in the last century), I built a continuity tester from a kit (which may have been from Audio Amateur), but can no longer find any info for it. The tester still works fine, and I frequently use it. Its PCB is labeled PE301A, uses an LM324 with a buzzer, is powered by a 9V battery, fits nicely in a 2.75"×4" black plastic box, has Voc = ~ 200mV, and Isc = ~ 270µA. Before I start tracing PCB tracks to reverse engineer this tester, and satisfy my curiosity about its operation, does anyone recognize it and perhaps have a schematic? Lots of web searching has not turned up anything.

author: hli
author_rank: Frequent Contributor
timestamp: March 24, 2014, 01:13:49 pm
content: It might be similar to the one Conrad still sells:http://www.conrad.com/ce/en/product/199842/Conrad-Continuity-Tester-PCB-Kit#download-dokumente. This ones uses a LM741 for continuity detection and a CD4093 for driving the piezo buzzer. I own this one since about twenty years or so... Unfortunately there is no user manual in English, but at least it contains the schematic (page 21, value on page 15).

author: Wh1sper
author_rank: Regular Contributor
timestamp: July 16, 2014, 06:36:05 pm
content: Hint:https://www.eevblog.com/forum/testgear/multimeter-with-low-continuity-test-voltage/msg480122/#msg480122With only 1 diode one are able to drop the voltage down to the diode flow voltage. In my case a Germanium Diode = 0.4V

author: electronic_eel
author_rank: Regular Contributor
timestamp: July 18, 2014, 08:17:17 pm
content: Here are a bunch of continuity tester schematics collected:http://kripton2035.free.fr/continuity-repos.htmlMaybe your schematic is in there too.

author: Wh1sper
author_rank: Regular Contributor
timestamp: July 18, 2014, 08:59:40 pm
content: Quote from: electronic_eel on July 18, 2014, 08:17:17 pmNice Site, thanx!
384x288 Thermal imager for <$1000, no hack required! - Page 1
Forum section: electronics / testgear

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: July 21, 2014, 12:56:52 pm
content: Opgal have just dropped the price of their Android thermal imager from $1600 to $999 :http://therm-app.com/product/therm-app-device/?utm_source=activetrail&utm_medium=email&utm_campaign=Therm-App%20Price%20Promotion-%20July<9fps obviously, but interchangeable lenses. interestingly the website pics show a much smaller lens on the "$999" banner image- I wonder if they are doing a Flir and downsampling a higher rate image to allow a cheaper lens.Mailshot :QuoteMy guess is that they got a lot of initial interest but everyone choked on the original price, thinking it would be in Flir One territory!

author: frenky
author_rank: Unknown
timestamp: July 21, 2014, 01:08:21 pm
content: They have interchangeable lens:Quote:For instance, with its interchangeable lenses, the Therm-App™ device provides effective detection of faraway targets through its long range (19 mm) lens, and a wider view through its 6.8 mm lens.What’s is in the package1 Therm-App™ Device1 19mm Lens2 USB-OTG Cables1 Ergonomic HandleProduct DocumentationIt seems that 6.8mm lens are not included.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: July 21, 2014, 01:17:13 pm
content: You'd think they could have sourced a more elegant right-angled USB cable though....

author: omgfire
author_rank: Regular Contributor
timestamp: July 21, 2014, 01:19:23 pm
content: Stated focus range from 0.6 m.

author: frenky
author_rank: Unknown
timestamp: July 21, 2014, 01:31:39 pm
content: Quote from: mikeselectricstuff on July 21, 2014, 01:17:13 pmOr put usb socket on the side that is parallel with bottom of a phone.

author: leppie
author_rank: Frequent Contributor
timestamp: July 21, 2014, 02:03:54 pm
content: Seems as soon as a little optics is involved, people charge a fortune...
Looking for a multimeter with waveformdisplay(scope?) - Page 1
Forum section: electronics / testgear

author: avinandan012
author_rank: Newbie
timestamp: July 17, 2014, 07:36:31 am
content: Hi All,This is my first post I am a old viewer of EEVblog youtube channel.I am looking for something which can display waveforms.The device will be used mostly to test UPS output in India(230V 50Hz) and a few Arduino based hobby projects. Not high precision is required only to measure so-called cheap sinewave UPSs out there.Budget is around Rs.14000(US $230). I searched around a little bit and came across UNI-T UT81B Scopemeter.Please suggest. Thanks for your time.

author: jpb
author_rank: Super Contributor
timestamp: July 17, 2014, 10:01:05 am
content: If you want it to be portable and also act as a multimeter then a handheld scopemeter is probably your only option and good makes like Fluke are very expensive.Hantek do one but even that is probably a bit more than $230 (it is around £250 in the UK I think) - perhaps Google scopemeter to find some reviews.If you're testing the UPS at your bench and you have a bit of space then perhaps getting a second hand and cheap analogue scope along with a separate DMM might be a better solution.

author: omgfire
author_rank: Regular Contributor
timestamp: July 17, 2014, 10:03:08 am
content: I doubt that UT81B can show UPS switch process: switchover time, overshoot.
Hakko FR-802 220v internal pics + Teardown - Page 1
Forum section: electronics / testgear

author: TheBorg
author_rank: Frequent Contributor
timestamp: June 04, 2014, 03:47:49 am
content: I was requested by another user for some internal pictures of my Hakko FR-802 hot air rework station, so I figured I'd post them on here, as internal pics are near impossible to find on the internet. Not a proper teardown (hey, I'm still working on a channel name), but it should suffice for most uses. I can help identify parts or take more pictures if needed.Pics are embedded from Flickr, couldn't get the server here to upload all of themhttps://www.flickr.com/photos/68788856@N03/sets/72157644995109552/P2350874byphotogeek121, on FlickrP2350877byphotogeek121, on FlickrP2350878byphotogeek121, on FlickrP2350879byphotogeek121, on FlickrP2350880byphotogeek121, on FlickrP2350881byphotogeek121, on FlickrP2350883byphotogeek121, on FlickrP2350885byphotogeek121, on FlickrP2350886byphotogeek121, on FlickrP2350887byphotogeek121, on Flickr

author: Zucca
author_rank: Unknown
timestamp: June 04, 2014, 04:03:44 am
content: Nice! Finally, the www needed those pictures!More infos:Datasheethttp://www.tequipment.net/assets/1/26/Documents/Hakko/fr802-11-datasheet.pdfUsers Manualhttp://www.tequipment.net/assets/1/26/Documents/Hakko/fr802-11.pdfMaintenance Guidehttp://www.tequipment.net/assets/1/26/Documents/Hakko/fr802-11-maintenance.pdf

author: TheBorg
author_rank: Frequent Contributor
timestamp: June 04, 2014, 04:09:56 am
content: Yeah!I think I'm gonna try to do a full on teardown if I can find the time, and get some uncluttered pics of the board. Anyways, kudos to zucca for posting related info!!

author: TheBorg
author_rank: Frequent Contributor
timestamp: July 16, 2014, 04:24:53 pm
content: Finally got the teardown uploaded. I think I'm going to stay away from full 1080p HD though, my camera can handle it fine but my computer took three hours to encode and six hours to upload an 18 minute videoWithout further delay, here you go.Complete with a lot of ums, sooo's, and first video issues. It can only get better, right?Thanks for watching, and if you have any comments or suggestions let me know!
Keithley 195a issues - Page 1
Forum section: electronics / testgear

author: eyehat
author_rank: Newbie
timestamp: July 16, 2014, 03:16:23 am
content: Hello everybody. I just bought a Keithley and boy is it grand. The d.c. volt, and ohm readings are spot on, original calibration was all that was done to it from factory. I was quickly disheartened though, as when I pressed the button for a.c. voltages or amps it showed no op. Which after diving through the manual means that the 1950 option is not present. My question to any one out there is what did that option consist of; is it some rom chips, a breakout board and would it be in the realm of possibility to find one and flash some roms if any body has them?

author: lowimpedance
author_rank: Super Contributor
timestamp: July 16, 2014, 03:46:06 am
content: Not a ROM change, but requires good old analogue electronics (see the manual for details).The plug in PCB contains current shunts plus relays and other switching as well as a AD636 plus its associated parts for the TRMS part.In short its not the easiest thing to re create (cost wise). Cheaper to buy another 195a with that option installed!.However its still an excellent meter.I have two, one with the option and one without.Such a PITA having these things as 'OPTIONS', but that was the way it was done so it pays to investigate a prospective purchase to make sure it does contain options for functions you would have expected to get.

author: eyehat
author_rank: Newbie
timestamp: July 16, 2014, 01:07:41 pm
content: Thank you for letting me know. I wasn't too concerned with having those options, I paid $10 for it and it is a superb meter without the other options. Thats what I assumed, I'll keep an eye out for another as a donor or as another meter (I tend to hoard equipment).
Tektronix MSO2024B teardown - Page 1
Forum section: electronics / testgear

author: kilohercas
author_rank: Regular Contributor
timestamp: July 15, 2014, 03:29:54 pm
content: http://youtu.be/O7yuHvA1skU?list=UUDBSFAz0IZN4Jjs07bH1XqQMSO2024B teardown

author: AndyC_772
author_rank: Super Contributor
timestamp: July 15, 2014, 04:47:41 pm
content: I was really surprised to see that MPC870 processor, it's a dinosaur!PowerPC core, 133 MHz core / 66 MHz SDRAM memory (no DDR capability), and the internal peripheral set is designed for networking and communications. If you wanted to build a product with a couple of 10/100M Ethernet ports and an RS232 interface ten years ago then it was a good choice at the time, but I'm amazed to see it in a relatively new design.

author: kilohercas
author_rank: Regular Contributor
timestamp: July 15, 2014, 05:23:39 pm
content: Well, MSOX2000 is much better choice, but MSO2024B have some advantages, major will be easy application module hack, with 0.50$ EEPROM
Anyone wanna see a teardown? - Page 1
Forum section: electronics / testgear

author: Velkozsolomid
author_rank: Newbie
timestamp: July 14, 2014, 05:38:49 am
content: My dad passed down to me an Olson TE-380 multimeter. It has the original receipt in the box from 30ish years ago. if you were to google olson te-380 the first couple flickr results should be of mine. if anyone wants to see more pictures of a teardown i just may. i dont have any kind of recording/video editing setup so a teardown vid is probably out of the question. was inspired to share this after i saw the triple teardown david had done. that is all-mj

author: mimmus78
author_rank: Unknown
timestamp: July 14, 2014, 09:07:17 pm
content: Why bother asking ... just (un)do it!
A look at the innards of the DS1074Z-S - Page 1
Forum section: electronics / testgear

author: jlothian
author_rank: Newbie
timestamp: July 12, 2014, 12:40:28 am
content: Some detailed pictures of the innards of my DS1074Z-S:https://www.flickr.com/photos/jameslothian/sets/72157645222357567/.Cheers,James

author: Bryan
author_rank: Frequent Contributor
timestamp: July 12, 2014, 06:27:19 am
content: Thanks for sharing. The power supply at least looks easy to service if ever needed

author: sfiber
author_rank: Regular Contributor
timestamp: July 13, 2014, 07:29:08 pm
content: thanks man.Do you a know a way to hack this scope to add screen saver.

author: electronics man
author_rank: Frequent Contributor
timestamp: July 13, 2014, 07:57:15 pm
content: so the function generator is just a plug in board, so may it make it possible in the future to upgrade the ds1074 to the ds1074z-s?

author: pmcouto
author_rank: Unknown
timestamp: July 13, 2014, 08:37:47 pm
content: Oh no!Capxon caps in the PSU...

author: Mark_O
author_rank: Frequent Contributor
timestamp: July 14, 2014, 03:06:09 pm
content: Quote from: jlothian on July 12, 2014, 12:40:28 amNicely done. Thank you.

author: Bryan
author_rank: Frequent Contributor
timestamp: July 14, 2014, 07:55:41 pm
content: Quote from: pmcouto on July 13, 2014, 08:37:47 pmThus why I said....The power supply at least looks easy to service if ever needed

author: jeremy
author_rank: Super Contributor
timestamp: July 14, 2014, 08:07:47 pm
content: What is the board with the six relays and cyclone? Function gen I presume?Also, has anyone worked out what the secret chips on the main board are yet ? (The ones with the top burned off)