hybridfree/eevblog-posts huggingface dataset:
Mastech MS8040 bench DMM back-light problem [solved] - Page 1
Forum section: electronics / testgear

author: enut11
author_rank: Super Contributor
timestamp: May 31, 2016, 11:21:39 am
content: Hi. I have just purchased a Mastech MS8040 bench multimeter. It has 5 digits and good accuracy for the price (~$200AU). Sits on my bench and gets used most days.The MS8040 has a large, easy to read LCD display with back-light capability.My problem: the back-light has to be switched on manually and only stays on for less than 1 min, despite the unit being powered from 240vAC.When I am taking lots of measurements, it is a pain to continually press the back-light button to read the display.Any suggestions on how to modify the unit so that the back-light stays on permanently or at least 10 min or more?enut11

author: tautech
author_rank: Super Contributor
timestamp: May 31, 2016, 11:54:06 am
content: If there's no menu option to permanently enable it a hack should be possible.If it lights instantly with a push and hold of the button a bodge wire across the pads or terminals nearby should do the trick.Have you tried multiple pushes to see if there's a lock on feature?

author: xrunner
author_rank: Super Contributor
timestamp: May 31, 2016, 12:35:11 pm
content: Sometimes the controller IC expects to see a pulse from the switch, so simply making that line closed all the time with a wire might not work, you'll have to try it. It probably has an EL backlight so you might have to look at wiring that permanently to power.

author: enut11
author_rank: Super Contributor
timestamp: June 01, 2016, 06:03:20 am
content: Quote from: tautech on May 31, 2016, 11:54:06 amThe yellow button toggles the back-light on and off. Holding the button on just makes the buzzer scream. Multiple pushes don't work either.

author: enut11
author_rank: Super Contributor
timestamp: June 01, 2016, 06:04:51 am
content: Quote from: xrunner on May 31, 2016, 12:35:11 pmWhat do you mean by EL?

author: TheSteve
author_rank: Unknown
timestamp: June 01, 2016, 06:54:17 am
content: EL = electroluminescent panel.

author: xrunner
author_rank: Super Contributor
timestamp: June 01, 2016, 11:48:20 am
content: Quote from: enut11 on June 01, 2016, 06:03:20 amThat's what I thought was going to happen. It's under the control of a microcontroller or microprocessor. You'll need to hard-wire the back light to it's supply if possible.

author: enut11
author_rank: Super Contributor
timestamp: June 01, 2016, 12:39:40 pm
content: Thanks All. I decided to hard wire the EL back-light panel so that it comes on with the main power switch. Works well.The MS8040 back-light panel works off ~6 volts and draws ~60mA. The pins were marked A and K so I assumed a diode array. I disconnected the array from the main PCB.I then wired an LM317 in constant current mode by soldering a 20 ohm 1/2W resistor between adjust and output pins. The input to the 317 was at the main filter cap (+25V). The adj pin on the 317 was wired to the 'A' terminal on the back-light panel. The panel return 'K' was taken to a convenient earth point. Dissipation is about 1W in the 317.enut11
6 GHz Vector Network Analyzer for under 1500,- USD ? - Page 1
Forum section: electronics / testgear

author: rfspezi
author_rank: Regular Contributor
timestamp: May 30, 2016, 02:14:45 pm
content: Has anybody got a hint on a vector network analyzer (up to 6 GHz) for under 1500,- USD?The VNAs i found so far that lie within that price range are only supporting 3 GHz and/or have poor dynamic range.thanks
HP E2050A Mini-Teardown - Page 1
Forum section: electronics / testgear

author: amc184
author_rank: Regular Contributor
timestamp: May 08, 2016, 08:17:38 am
content: I had this out on my bench today, and thought I'd do a small teardown, as I haven't seen much about it on the net. The E2050A is a LAN to GPIB gateway, basically operating as a small PC with a network and GPIB interface that passes on GPIB commands from networked PCs.The construction is pretty simple, just a sheetmetal lid and base. There's a single PCB of at least four layers with a double sided load. I haven't photographed the bottom side, but it's mainly decoupling (lots of tantalums) and termination resistors.The main functional blocks on the left hand side of the board seem to be:ROM - two flash memories with a MAX734 flash programming supply and LT1811 RS232 transceiver (the RS232 port looks to be for firmware upgrades and maybe debigging).Ethernet - MC68160 ethernet transceiver, NQ83C92 transceiver for the 10BASE2 (yes, it's that old), isolated by a Bel S553 transformer and DPS0502B isolated switching module, and a PE-68011 transformer for the 10BASET.The main functional blocks on the right hand side of the board seem to be:Embedded PC - MC68EN360 microprocessor with two KM416C256 DRAMsGPIB - MP9914 GPIB controller with some ALS logic series driverssome miscellaneous logic to driver the front panel LEDsIt's a great device to use after it's setup (the setup can be trying, like many older networking devices it's not user friendly). Unlike the other GPIB options (USB and PCI) there's no cable length issues, your PC can be as far from your test gear as you want. The front panel LEDs can give you a brief summary of what's happening on the GPIB bus as well. Overall, a great little tool.

author: gslick
author_rank: Frequent Contributor
timestamp: May 30, 2016, 02:50:37 am
content: Quote from: amc184 on May 08, 2016, 08:17:38 amYou can connect a terminal or PC running a terminal emulator to the E2050A RS-232 port using a null modem cable at 19200,N,8,1 and after hitting <CR> it should bring up the configuration menu. That is lot easier to than figuring out how to telnet into the E2050A to do a factory-reset and then configure it for your local network parameters.Too bad the manual only says "Note that the RS-232 interface is NOT supported for I/O application use." and doesn't say that it can be used to access the configuration menu directly without a network connection.

author: amc184
author_rank: Regular Contributor
timestamp: May 30, 2016, 05:45:29 am
content: Yeah, now you mention it I might have known that at some stage. I used telnet, and it's not a particularly easy process. I remember spending a frustrating afternoon getting it set up, but it worked perfectly after that.
Feeltech function generator - Page 1
Forum section: electronics / testgear

author: Rhys
author_rank: Newbie
timestamp: May 29, 2016, 10:51:59 am
content: Hi just got a feeltech generator model FY2200 REV 3.0 which goes to 2 MHZ.I have found by pressing the menu button and switching it on at the same time it extends the output frequency to 20MHZ.Just thought it may be of intrest to any one that has one.Rhys

author: JoeO
author_rank: Frequent Contributor
timestamp: May 29, 2016, 11:40:53 am
content: Link?

author: xrunner
author_rank: Super Contributor
timestamp: May 29, 2016, 12:22:10 pm
content: Quote from: Rhys on May 29, 2016, 10:51:59 amIs it this thing?Feeltech 2200There are quite a few models that all look the same but have different max freq. specs but have no labelling to that effect on the front panel. Looks like you found a trick around that.

author: Rhys
author_rank: Newbie
timestamp: May 29, 2016, 01:20:18 pm
content: Hi yes thats the one underneath says FY2200 2MHZ.
Brymen BM878 -- where to buy? - Page 1
Forum section: electronics / testgear

author: iXod
author_rank: Frequent Contributor
timestamp: May 29, 2016, 01:26:59 am
content: No one seems to have stock. Anybody have eyes on one?I'm in USA but now days that's not really important re buying. Anywhere would be good.Thanks.

author: whitevamp
author_rank: Regular Contributor
timestamp: May 29, 2016, 01:53:19 am
content: Quote from: iXod on May 29, 2016, 01:26:59 amif you mean BM878 quite a few polish and Russian have them.http://www.ceneo.pl/35693364http://www.biall.com.pl/item,BM878-Multimetr-TRMS-VFD-Temp-rezystancja-izol-50-1000V-Earth-Cont-200mA,102133.htmland more..

author: iXod
author_rank: Frequent Contributor
timestamp: May 29, 2016, 06:35:18 am
content: I don't think Extech is rebranding this model. I don't see it in their catalog:http://www.extech.com/instruments/categories.asp?catid=48

author: Unknown
author_rank: Unknown
timestamp: May 29, 2016, 08:37:26 am
content: I think this site was posted by joe smith (testing multimeters on youtube). I also believe he ordered from there with no problem.http://www.tme.eu/en/details/bm878/portable-digital-multimeters/brymen/

author: iXod
author_rank: Frequent Contributor
timestamp: May 29, 2016, 09:41:20 pm
content: "Stock level: 0"Looking for site with... well, stock.Thanks.

author: Unknown
author_rank: Unknown
timestamp: May 29, 2016, 11:15:09 pm
content: Ah, didn't notice. That looks like an elusive meter. Maybe send a inquiry to Franky Tong, whose based in Hong Kong (search forum for contact info). He may be able to direct you to an Asian source.

author: iXod
author_rank: Frequent Contributor
timestamp: May 30, 2016, 02:14:41 am
content: Good idea.Searched forum for Frank but nothing.Do you have email for him?Thanks.

author: retiredcaps
author_rank: Super Contributor
timestamp: May 30, 2016, 02:16:30 am
content: Quote from: iXod on May 30, 2016, 02:14:41 amhttps://www.eevblog.com/forum/profile/?u=26834

author: iXod
author_rank: Frequent Contributor
timestamp: May 30, 2016, 03:15:09 am
content: Thanks!
Keysight U1272a DMM: Which PTCs in LOW Z Mode? - Page 1
Forum section: electronics / testgear

author: ElektronikLabor
author_rank: Regular Contributor
timestamp: March 04, 2016, 08:58:36 pm
content: Hello,today I noticed, that when I measure 1kV with the U1272a DMM in Low Z mode, the DMM gets a bit warm on a certain area of the surface (42°C / 108°F).This Area is exactly where the PTCs are mounted on the PCB. What is the P/N of that PTCs which are used for that function?There are four PTCs; I presume they are connected in series?I hope I don't overdrive them with 1kV?You can see the PTCs on daves Video (Dave is pointing at them); unfortunately they are heatshrinked.BTW: The PTCs are drawing 1mA when 1kV is applied

author: electr_peter
author_rank: Unknown
timestamp: May 29, 2016, 09:54:46 am
content: Checked U1272A connected to 230V AC mains on Low Z mode. After 20 seconds, surface temperature at the right of rotary switch reached 35-38 C and continued to climb at very slow rate.Not an issue in my opinion, temp increase is minimal. Heat from low resistance mode has to go somewhere.
what is it worth??  - Page 1
Forum section: electronics / testgear

author: panos1b
author_rank: Newbie
timestamp: May 28, 2016, 05:44:23 am
content: i found my dads old multimeter (fluke 8024a) eny ideas on what it is worth it does work

author: ataradov
author_rank: Super Contributor
timestamp: May 28, 2016, 06:08:46 am
content: Quote from: panos1b on May 28, 2016, 05:44:23 amThere are a lot of similar units on eBay and they seem to advertised for $20-$100 depending on a condition.

author: Fungus
author_rank: Super Contributor
timestamp: May 28, 2016, 09:44:23 am
content: Quote from: panos1b on May 28, 2016, 05:44:23 amDepends on the condition and whether or not it has all the boxes, manuals, etc.Will you be rich? No.

author: ataradov
author_rank: Super Contributor
timestamp: May 28, 2016, 04:32:53 pm
content: Yes, manuals alone go for $20.

author: bitseeker
author_rank: Super Contributor
timestamp: May 29, 2016, 07:15:02 am
content: A couple of listings of that model in working condition recently sold on eBay for around $30 without a manual.

author: AndreasF
author_rank: Frequent Contributor
timestamp: May 29, 2016, 09:38:27 am
content: Might be worth a little bit more since you're in Europe. All the listings I can see (apart from a manual listed in Italy) are in the US.
Hameg HM604 service manual - Page 1
Forum section: electronics / testgear

author: gyrionis
author_rank: Newbie
timestamp: September 17, 2014, 05:08:36 pm
content: Hello to everyone.I recently bought a used Hameg HM604-2.It's a nice old piece of equipment, but it has got some difficulty in auto triggering. I think it needs a good calibration, for starters. These 2 manuals:http://service-manual.eu/model.php?id=356, aren't detailed enough. I rather need something like this to do the job:http://service-manual.eu/model.php?id=2597.Hameg calls it "adjusting plan".Any ideas?

author: Bored@Work
author_rank: Super Contributor
timestamp: September 17, 2014, 05:44:57 pm
content: Contact Hameg. They provide service manuals for their older equipment for free. AFAIK when they no longer provide service on their own for some equipment they provide the service manual for free.

author: anotherlin
author_rank: Frequent Contributor
timestamp: September 18, 2014, 08:52:24 am
content: Quote from: Bored@Work on September 17, 2014, 05:44:57 pmI can confirm that. Just send them (Hameg) on email and they should send you the pdf.I had a problem with an older version of their 8000 series rack PSU module, they've sent me the service manual.

author: blacknoise
author_rank: Contributor
timestamp: September 18, 2014, 12:04:59 pm
content: I found a combined operating and service manual including schematics for the HM604-2 on my server and uploaded it there:http://ul.to/xg6wffhx(only in german laguage and lower but readable quality)

author: gyrionis
author_rank: Newbie
timestamp: October 04, 2014, 12:41:29 am
content: 1. Thank you all for your replies. I contacted Hameg and they sent me the service manual which is not so extended as the one that blacknoise posted above (Thx blacknoise). Apart from that, they've also sent me the first revision of HM604 which I upload herehttp://ul.to/geithi8e,http://ul.to/a94cmlub, in case somebody else needs it.2. I noticed that when I tapped the left Volts/div switch, the input signal gets distorted. So before tackling the calibration process, I believe it's the right time to give a nice clean to the contacts.Here are some photos of channel 1. Needless to say that reaching this guy was a pain in the a**.The contacts were cleaned with a generous load of IPA.Bits and pieces waiting to be fitted back on the front panel.Cheers.

author: RNA2
author_rank: Newbie
timestamp: May 29, 2016, 08:09:16 am
content: Hi gyrionis,can you pls explain how you did the cleaning?What solvents did you use and what parts did you have to open /examine?I have a similar problem with an hameg 604 where the vol/div switch seems to be out of function.Turning is very hard, like glued with resin or something...Thank you!
good pocket multimeter for the glove box - Page 1
Forum section: electronics / testgear

author: timbob
author_rank: Contributor
timestamp: May 28, 2016, 12:33:39 pm
content: Hello, I bought a Victor VC921 for my car a few years ago, when I had to use it for my car the the screen had die but the meter still turn on. does any one know a good pocket multimeter that I can leave in my car and not worry about it dieing before I need it? I am in Illinois. it need to with stand, and im going with extremes -37 °F (-39 °C) up to 117 °F (47 °C).

author: Fungus
author_rank: Super Contributor
timestamp: May 28, 2016, 12:46:20 pm
content: Fluke 101 - Fluke's "extremely rugged" multimeter.http://www.fluke.com/fluke/inen/digital-multimeters/compact-multimeters/fluke-101.htm?pid=77003You can get them shipped to your house for under $42:http://www.ebay.com/sch/i.html?&_nkw=fluke+101

author: Wytnucls
author_rank: Super Contributor
timestamp: May 28, 2016, 01:04:42 pm
content: LCD screens don't like extreme temperatures and can suffer permanent damage.

author: Fungus
author_rank: Super Contributor
timestamp: May 28, 2016, 01:28:41 pm
content: Quote from: Wytnucls on May 28, 2016, 01:04:42 pmYes, but good luck finding a non-LCD handheld multimeter.Fluke 101's storage temperature range is -30 °C to +60 °CTo beat that you'd have to go to something like a Fluke 28 II:TemperatureOperating-15 °C to +55 °C, to -40 °C for 20 minutes when taken from 20 °CStorage-55 °C to +85 °C (without battery) -55°C to +60°C (with battery)But a Fluke 28 II is alotmore expensive.(And a lot bigger - I don't know how big your glove box is, or how full...)

author: nctnico
author_rank: Super Contributor
timestamp: May 28, 2016, 01:37:10 pm
content: It is better store a DMM in a different place. A cool place would be under the seats or in the trunk next to the spare tire.

author: Len
author_rank: Frequent Contributor
timestamp: May 28, 2016, 06:41:03 pm
content: Quote from: Fungus on May 28, 2016, 01:28:41 pmSo it's OK formostof the year.

author: Fungus
author_rank: Super Contributor
timestamp: May 28, 2016, 07:24:39 pm
content: Quote from: Len on May 28, 2016, 06:41:03 pmTo be fair: The "-37°C" figure is anunofficalrecord low,only seen onceand not ratified.If the Victor VC921 lasted a few years then the Fluke 101 will probably be OK.

author: timbob
author_rank: Contributor
timestamp: May 29, 2016, 07:51:54 am
content: Quote from: Fungus on May 28, 2016, 07:24:39 pmthanks for all the info, I was just went with the extreme what wiki had listed. I will buy the fluke 101 and try it out
Fluke 289 - save default settings for rotary switch? - Page 1
Forum section: electronics / testgear

author: aronake
author_rank: Frequent Contributor
timestamp: May 28, 2016, 02:22:29 pm
content: The Fuke 289 manual say on page 14:"Menu selections are remembered for each rotary switch position.For example, selecting REL for the volts ac position causes RELto be selected the next time the menu is opened in volts ac, eventhough in the interim, Hz,%,ms was selected from a similar menufor the millivolts ac function."this seems not to be the case for me. In say the Diode/Capacitance switch setting, even though i set it to Diode mode, and use that, then choose other mode with rotary switch and back to Diode/Capacitance switch setting it defaults to Capacitance mode.Same for resistance/continuity testing, allways defualt to resistance.Is there some setting i missed, or have they changed this in the newer firmware? or some way to set the default setting when withing to a mode with the rotary switch?

author: Zermalmer
author_rank: Regular Contributor
timestamp: May 28, 2016, 09:01:42 pm
content: Hi aronake,The part of manual you are referre is related to the function menu.If I understand it right they always mean the function menu settings are the same if you return to a measurement method and not that the choosen method is selected if you move rotary switch in a position, where more than one measurement function is available.Best regardsAndreas

author: serggio
author_rank: Regular Contributor
timestamp: May 29, 2016, 05:56:13 am
content: Quote from: aronake on May 28, 2016, 02:22:29 pmThis work exactly as mentioned in manual. Meter remember menu selection for each rotary switch position. This can help you return to secondary function by pressing only two buttons, for example Menu - C for measuring temperature, if Temp function was last selected for mV position.
I Bricke my Siglent SDS1062CM Oscilloscope - Page 1
Forum section: electronics / testgear

author: wenpaul
author_rank: Newbie
timestamp: May 29, 2016, 02:09:04 am
content: Hello guys.I got the siglent sds1062cm,after uploading the incorrect firmware. When I turn on the Oscilloscope , nothing is displayed only bright screen. USB does not work. I have a FLASH Programmer,and I also have a URAT and JATG?but i dont know how to doThese are the main board photos~~~Maybe no one has this oscilloscope .But I know the sds1062cm and other oscilloscope circuit are almost the same.Could you please provide some reference methods for me?Thank you !

author: xrunner
author_rank: Super Contributor
timestamp: May 29, 2016, 02:14:08 am
content: Oh dear - my sympathies.How did you make the mistake of uploading the wrong firmware?

author: wenpaul
author_rank: Newbie
timestamp: May 29, 2016, 02:20:15 am
content: But this backfire when I think I can hack the oscilloscope
tek cfg280 repair - Page 1
Forum section: electronics / testgear

author: Rgreen50
author_rank: Newbie
timestamp: March 08, 2015, 03:40:49 pm
content: Hi everyone!I have an old Tektronix cfg280 function generator that seems to only go to 8 MHz +- but otherwise functions normally. I can find a service manual so was wondering if anyone here could help me fix this problem or maybe help me find the service/repair manual.Rick

author: tautech
author_rank: Super Contributor
timestamp: March 08, 2015, 06:44:35 pm
content: Might be best if you posted in the Repair board where more fixit members hang out.Plenty of links to sites for manuals there too.

author: ajjj1000
author_rank: Newbie
timestamp: June 01, 2016, 10:49:39 pm
content: I bought one of these CFG 280 function generators on ebay to repair but when I got it there were 3 IC's missing. I found one on ebay but the other 2 are not to be found. Anyone have a used 16V6-10LP and a 16V8-15LP IC's they would sell? Email me at ajjj1000@yahoo.com. Thanks,Arnold.Quote from: Rgreen50 on March 08, 2015, 03:40:49 pm

author: PA0PBZ
author_rank: Super Contributor
timestamp: June 02, 2016, 10:02:33 am
content: Quote from: ajjj1000 on June 01, 2016, 10:49:39 pmThose are programmable logic, you not only need the IC's but they have to be programmed for that specific fg.Good luck with that...

author: Richard Head
author_rank: Frequent Contributor
timestamp: June 02, 2016, 10:08:09 am
content: I think what you bought was a donor unit.
Cheap Harbor Freight probe holder - Page 1
Forum section: electronics / testgear

author: joeqsmith
author_rank: Super Contributor
timestamp: May 27, 2016, 01:18:52 am
content: I am still thinking it needs some sort of stage to fine adjust the position and a cheap camera. Machined the clamp and used a small section of Teflon to prevent damage to the probes. $32 and you get some free vice grips and a dial indicator... It uses the standard thread and will screw into their magnetic mount but it's just not stable enough and needs a wider base IMO.http://www.harborfreight.com/clamping-dial-indicator-93051.html

author: electronupdate
author_rank: Regular Contributor
timestamp: May 27, 2016, 08:32:27 pm
content: Interesting! I built something similar and I can say that the addition of a camera can really make it easy to drop the probe in the right place.

author: joeqsmith
author_rank: Super Contributor
timestamp: May 27, 2016, 10:11:10 pm
content: Nice job. Looks like it works good.
A few questions about the Rigol DS1054Z - Page 1
Forum section: electronics / testgear

author: metrologist
author_rank: Super Contributor
timestamp: May 27, 2016, 03:47:21 pm
content: I just received my scope last night and spent a couple hours getting familiar with it. So far it's great!I recall watching a video by one of the popular youtubers (mjlorton, I think) where he was using a scope to measure the voltage of LiPo battery while being charged. This was a long term measurement (hours, I think) and I wanted to make a similar measurement with my DS1054Z. Can it do it?This is where I got confused about the waveform record, which I thought I could use. Here is what I thought given the numbers in the manual:Interval max is 10 sFrames (or segments) I thought I read somewhere was 5000 max (but this is not the case as it appears to be a calculated max)Using my first assumption, I calculated 10 s * 5000 = 13 hours. I thought I would set a 10 s sweep, but then record is not available.If sampling rate is set to 12 kSa/s, then with 1 GSa/s, you'd get 23 hours, so I thought I'd use the Roll mode - but again no recording is available (which I then found the recording limitations in the manual).Now I am also aware of this formula:MDepth = SRate * TScale * HDivsand that is indicated for each Frame (which they actually call Length).This seems to be a limit:Mdepth = 24,000,000Srate = 12,000 Sa/sHdiv = 12 divs (a constant)Tscale = 0.000165 s or lessper frame.I'll have to work out the math on some of my settings, but I came across a few scenarios where I could not increase the Interval to more than or less than 100ns and only 2 Frames, and my time base was set around 8 MHz to probably around 100 kHz (I was looking at an 8 MHz 5-pulse burst with a repetition rate of around 1 MHz). I do not have the scope with me now, but these are two things that did not get completely resolved on my first run-through of knob twisting...

author: Fungus
author_rank: Super Contributor
timestamp: May 27, 2016, 06:37:26 pm
content: Quote from: metrologist on May 27, 2016, 03:47:21 pmThe lowest a DS1054Z can go is 50 seconds per horizontal division.There's 12 divisions so that's 10 minutes maximum recording time.

author: uncle_bob
author_rank: Unknown
timestamp: May 27, 2016, 07:01:14 pm
content: HiSince the scope can dump data via ethernet or USB, you can effectively extend the dataset using a computer. A bit of software coding and you can start filling up a disk drive with data points or full trace records..Bob

author: alsetalokin4017
author_rank: Super Contributor
timestamp: May 27, 2016, 09:01:10 pm
content: Record works at a horizontal timebase of 100 ms/div or faster. If you set Mem Depth at 12k in the Acquire menu, you can then record 5197 frames at an interval of 10 seconds between frames, each of which covers 1.2 seconds at 100 ms/div. This equals something like 16 hours of elapsed time, during which about 104 minutes of actual waveform time is recorded.
please help I need a good data logging DMM! 1.5Kv Range! - Page 1
Forum section: electronics / testgear

author: 13Nike
author_rank: Newbie
timestamp: May 28, 2016, 07:34:39 am
content: Hello everybody,I am currently working on a research project and need to record the IV curve of a plasma discharge. Our current setup is pretty cool. We just have a web camera setup and using python+OpenCV we make meter reading inferences based off true/false statements based around what segments of a 7 segment display are on. The problem is that sometimes the program confuses 0 and 8, 5 and 6, etc. We added statistical corrections but even then the hysteresis/lag between when I control the PS to the plasma discharge to the DMM's is too high.I need 2 meters (or 1 if possible) that can record and save the values I'm measuring either wirelessly, USB, etc. One to measure voltage that can reach up to 3kV (up to 1.5kV is manageable though) and one to measure current in the microamp range (as low as 10 uA).The current meters I have is a Fluke 116 for current measurement and a BK survivor 2860A which ironically busted a cap and died today. Anything around the spec level of those is okay. In terms of price I cant see my department paying over $1,000. Less than $500 is ideal. I'd prefer a vendor that gives educational institutions a discount.I've been searching for a while and I like the fluke Connect brand especially the FC 3000 but they dont seem to have a line whose voltage range is above 1,000VAny help is appreciated I looked at the excel sheet but didnt find a model with a voltage range

author: Wytnucls
author_rank: Super Contributor
timestamp: May 28, 2016, 09:15:22 am
content: Most multimeters are classed as low voltage (1000V) instruments. The Amprobe HD160C can measure up to 1500 VDC and 1000VAC, but it doesn't have a logging feature. That meter might be suitable, but the best option would be to use a high voltage probe (CAT I only!).http://en-us.fluke.com/products/all-accessories/fluke-80k-40.htmlhttp://www.amprobe.com/Amprobe/usen/Multimeters/Industrial-Multimeters-/AMP-HD160C.htm?PID=73247

author: Someone
author_rank: Super Contributor
timestamp: May 28, 2016, 11:13:50 am
content: Quote from: 13Nike on May 28, 2016, 07:34:39 amYou will need to do this with a HV probe of some sort, or build a suitable divider, but most HV supplies for lab use offer a proportional 0-10V output to make it easier to monitor. The current measurement is the hard part, are you measuring on the supply side and not referenced to ground? Doing that safely is way beyond your budget.Its probably time to get your local electronics tech to build a probing system for you and attach that to a cheap USB interface like the NI USB-6001/6002.

author: ebclr
author_rank: Super Contributor
timestamp: May 28, 2016, 11:36:21 am
content: With this probehttp://www.lutron.com.tw/ugC_ShowroomItem_Detail.asp?hidKindID=1&hidTypeID=4&hidCatID=&hidShowID=46&hidPrdType=&txtSrhData=and any datalogger multi-meter you can make some measurements at a reasonable price
Rigol DP832 chattery fan - Page 1
Forum section: electronics / testgear

author: alank2
author_rank: Super Contributor
timestamp: May 26, 2016, 07:29:16 pm
content: I noticed that on occasion, sometimes when turning it on and it spins quickly for a second, and sometimes just randomly, the fan on my new DP832 makes a chattery noise. If I press on the back cover, it will stop however. I saw someone else complaining about this same thing around here and wonder how common it is, if there are any fixes, etc.
New equipment for my lab! - Page 1
Forum section: electronics / testgear

author: neonhomer
author_rank: Contributor
timestamp: May 25, 2016, 02:40:50 pm
content: Just came back from Dayton Hamvention 2016, and picked up two new pieces of kit!First is a Siglent SDG1025 Function Arbitrary Waveform Generator, except this one has the SDG1050 board in it! Was a factory demo unit that was repaired, and they didn't have a 1025 board to put in, so they put a 1050 board in. Comes from Siglent w/ a 1yr warranty.Second is a Variac for 120VAC. Not much to tell about this one.That's about it... My next item I want to acquire is a spectrum analyzer....

author: GreyWoolfe
author_rank: Unknown
timestamp: May 25, 2016, 09:05:27 pm
content: Good score on the AWG! Enjoy it.
Pasternack PE6008-50 thru term - Page 1
Forum section: electronics / testgear

author: joeqsmith
author_rank: Super Contributor
timestamp: May 24, 2016, 02:24:13 am
content: Had a few minutes so took one of these apart today (it had been damaged) and it uses a 1/4 axial part. I thought for fun I would improve the design by using four 200 ohm resistors to decrease the inductance. That was a bust. The capacitance to the case is really bad now. Think a couple of 100 ohm 1206s may fit from the pin to the case.Added picture showing what not to do.

author: joeqsmith
author_rank: Super Contributor
timestamp: May 24, 2016, 04:50:15 pm
content: Using four 200 ohm 1206s.

author: joeqsmith
author_rank: Super Contributor
timestamp: May 25, 2016, 04:54:22 pm
content: Two 100 ohm 1206's.
BK Precision 1743B ??  Good Price used - Page 1
Forum section: electronics / testgear

author: gooseEL34
author_rank: Regular Contributor
timestamp: May 19, 2016, 09:58:40 pm
content: Hey all.What should I expect to pay for a BK Precision 1743B mint used condition with manual? One here locally. Also, other than putting a meter on it and testing voltages, is there a good way to "test" a used PSU?ThanksTim

author: electrongeek
author_rank: Contributor
timestamp: May 23, 2016, 02:35:48 am
content: Do the voltage and current limit controls operate smoothly and within expected range?You might put a scope or AC voltmeter on the outputs under some load and verify ripple is within specs.

author: gooseEL34
author_rank: Regular Contributor
timestamp: May 23, 2016, 06:35:48 pm
content: Thanks. I went back and it was gone... Early Bird and worms and all.....
Fluke 8502A - Ohms Converter and Cal Memory help wanted - Page 1
Forum section: electronics / testgear

author: mamalala
author_rank: Unknown
timestamp: February 01, 2013, 06:28:51 pm
content: Hello all,i just got a Fluke 8502A bench multimeter. It has the current shunt, ohms converter, AC RMS and IEEE options installed. However, the Ohms Converter options is faulty.During power on it is not detected at all. Once the instrument finished the startup sequence, the ohms converter module starts to emit a rather high pitched, constant noise. Also, after a while it becomes rather hot. I already checked all the supply voltages and they are nicely in spec according to the manual, and look pretty clean on the scope.There is something strange about the module that i have. In the manual it is given as MIS-4110. However, the actual PCB has MIS-3110 etched on the backside, also etched there is "Rev S_", while on the front there is "Rev R" handwritten on it.Does anybody here have an idea where i could start too look for a fault in the module? As said, all the other functions/options work nice (didn't test the IEEE option yet due to lack of hardware for that). How is the module detected during startup? If someone has an ohm converter module that needs a new home, let me know.Also, somehow the manual is missing the section for the Cal Memory option completely. While it is mentioned in the index of section 6 of the manual that it's description supposedly starts at page 604-1, it is completely missing. After 603-1 it continues with 605-1. I would be interested in a schematic for that to see if i may be able to build one myself.Thanks and greetings,Chris

author: whitevamp
author_rank: Regular Contributor
timestamp: May 05, 2016, 06:55:31 am
content: I know this is a way old post but was wondering if you still needed the Cal Memory diagram? if so i can post it for you.Im having a different issue with my ohms card mine its just way the heck out by a lot. 1k resistor shows 1150 and was checked with a diff meter. to show 999.and mine is making a noise as well.

author: retroware
author_rank: Contributor
timestamp: May 23, 2016, 04:03:37 pm
content: I'd be interested in the cal memory schematic. I plugged my cal memory into a powered on 8502a which made it very unhappy.
uCurrent spotted in HackRF tutorial videos - Page 1
Forum section: electronics / testgear

author: integritetus
author_rank: Newbie
timestamp: May 26, 2016, 08:43:59 pm
content: I was enjoying Michael Ossmann's excellent tutorial videos on software defined radios and his HackRF One product. In the background over Michael's left shoulder there appears to be the unique profile of a uCurrent sitting on top of what looks to be a power supply (HP E361x?).The tutorial videos are here:https://greatscottgadgets.com/sdr/The uCurrent is visible in the first seven videos.I couldn't find this sighting mentioned before in the forum. If it has been, apologies.Made me chuckle to recognize it.
Hantek DSO5102B nand dump or kernel image needed - Page 1
Forum section: electronics / testgear

author: divB
author_rank: Newbie
timestamp: May 23, 2016, 02:42:05 am
content: Dear Friends,Would someone be so kind as to provide the nand dump or kernel zimage for this model? My scope is stuck on the logo screen at boot. From uart debug, bootloader appears ok, but perhaps kernel is corrupted. Only had the dso for about a week before it bricked itself so unfortunately have no backup. Attached is putty log of the uart session. Have contacted hantek support but didn't receiver much assistance, scope has simply resided as a paperweight.Thank you most sincerely for any help.
Usb fuse for testing/lab purpose - Page 1
Forum section: electronics / testgear

author: badboy
author_rank: Contributor
timestamp: May 23, 2016, 07:38:35 am
content: I developed a simple USB fuse with different current threshold modes that is set by user mainly for lab purpose. In the linkl below u can get onehttps://www.eevblog.com/forum/buysellwanted/usb-fuse-for-sale/
Original install media and/or a bit-for-bit img for a 4 chan 500mhz 54825A - Page 1
Forum section: electronics / testgear

author: 2x2l
author_rank: Contributor
timestamp: May 19, 2016, 05:58:05 am
content: I copped one of these for a song, sans software. AFAICT there's nothing wrong with the display or acq, just the hard drive clicked-of-death'd (I mean it's a 20 year old IDE, bound to happen). So I guess I got a few questions1: Did Agilent do anything nefarious like flash their own proprietary firmware making it impossible to swap in a generic IDE? (I'm guessing no, since the service manual seems to imply that it's end-user servicable).2: The media it seems to come on was originally some sort of "Floptical" disk (in the 3.5" form-factor, but with the capacity of 120mb -- I'm guessing it must be something similar to those IOmega zipdrives, but regardless): Does anyone know where I can get one? If not, are blanks available ? I think my easiest way to solve this problem would be if a kind soul were to take their Infinium and image it byte-for-byte, so I can just whack the IDE drive into an old desktop and I might be good to go?3: I'm not an Agilent guy - am I tied to whatever software was on that Floptical stuff, or can I use more recent software and/or upgrade the consumer-end (the jellybean AMD 300, 64 mb RAM, hard disk, win 95 => Some late 90s vintage P3 running XP). Or hell, ideally an Atom would generate way less head, consume way less power, and easily out-perform the old stack that was in there.Just throwing around ideas, any advice would be appreciated.

author: 2x2l
author_rank: Contributor
timestamp: May 20, 2016, 07:56:56 pm
content: I'm hoping it's kosher to bump threads at least once so the day-crew can see this (I posted at like 4AM Eastern, presumably there's a few more active users now)

author: blacknoise
author_rank: Contributor
timestamp: May 21, 2016, 10:25:07 am
content: Maybe i have HD images that fit your 54825. Please look for the PM i wrote you (or tell me if you cannot access the PM).Best regards

author: mettlerr
author_rank: Unknown
timestamp: May 23, 2016, 02:20:42 am
content: Something like that?http://pdub.net/projects/agilent-recovery-cd/
ATTEN ADS 1102CAL Invalid USB Descriptor - Page 1
Forum section: electronics / testgear

author: PostNubila
author_rank: Newbie
timestamp: May 21, 2016, 02:09:50 pm
content: Hi,I have a ATTEN ADS 1102CAL (with no plus sign) which have the following configuration:Firmware version 3.01.01.31Hardware version: 6-41-2.1I connected it to my laptop with Windows 7 (32-bit), installed the driver and Easyscope and everything worked fine.Now, I'm trying to connect it to another laptop with Windows 10 (64-bit) and I'm not able to install its driver.Windows device manager shows the following:Unknown USB Device (invalid configuration descriptor)So, my questions are:Have you guys experienced the same issue?Did you find any solution?Is it possible to install it under Windows 10 or I have to keep a laptop with Windows 7 if I want to use Easyscope?Thank you in advance,Stanley.

author: tautech
author_rank: Super Contributor
timestamp: May 21, 2016, 02:18:47 pm
content: With Win 7 & 8 (don't know 10) you must have NI VISA installed FIRST as the USB drivers are NI supplied.The installed driver will have a filename something likeausbtmc.infFind it with a search, more than likely in the installed NI directory and make sure the scopes USB properties/driver points to that driver.Hope that helps.

author: tautech
author_rank: Super Contributor
timestamp: May 21, 2016, 02:27:34 pm
content: Attached is a doc on USB connection problems that I wrote some time ago with a link to a thread.
HP 8663A vs 8664A - Page 1
Forum section: electronics / testgear

author: danny_isr
author_rank: Regular Contributor
timestamp: May 23, 2016, 12:14:15 am
content: I was wondering if the 8664A is just a modern version of the same design of the 8663/2 ?I really like/admire the construction of the old 8662/3.Does the 8664a constructed the same (individual modules) ? is it just a newer better version ?thanks
Rigol DSO1104Z / 1054Z Logic Analyser Option? - Page 1
Forum section: electronics / testgear

author: dexters_lab
author_rank: Unknown
timestamp: May 21, 2016, 08:33:52 am
content: Does anyone have any experience with the logic analyser options for the Rigol 1054Z series?Been thinking about a new scope and could do with a logic analyser too so it might be a good option for mebut only if it's worth it and works wellwould spending the extra £ be better spent on the regular DS1054Z scope and a USB based LA?

author: tautech
author_rank: Super Contributor
timestamp: May 21, 2016, 08:55:47 am
content: Keep your eyes open for a soon to be announced LA addition to the Siglent range.Don't tell anybody, OK.

author: SteveyG
author_rank: Unknown
timestamp: May 21, 2016, 09:38:27 am
content: Quote from: dexters_lab on May 21, 2016, 08:33:52 amI have the logic analyser option on my MSO1074Z and IMO is worth is for the small extra outlay. It's quite good actually, obviously not on the level of the KS MSO3000 series I have at work but it does the job. I have a Saleae Logic 16, but it doesn't get as much use - the big advantage of the MSO is obviously you can display waveforms at the same time which can help with triggering or troubleshooting, however full protocol decoding is easier on the Logic 16 because you can easily scroll around the captured data. It depends what you want to do with it really.

author: dexters_lab
author_rank: Unknown
timestamp: May 21, 2016, 11:01:16 am
content: Quote from: SteveyG on May 21, 2016, 09:38:27 aminteresting comments, thanks Steve!
Dynatek 9020a teardown - Page 1
Forum section: electronics / testgear

author: jitter
author_rank: Frequent Contributor
timestamp: May 21, 2016, 10:15:18 am
content: Originally posted in the "Show your multimeter" thread, I decided that perhaps the teardown of my Dynatek 9020a DMM is better suited to a thread of its own, so I moved it here.Dynatek is not a very well known brand, seems to be isolated to this part of the world, but it's still around. As it was back when I got my 9020a, they're still rebrands, so that's why the currentDM3000might look familiar.It was my first "serious" multimeter, previously having had those cheapos we all know too well. This one was as much as I could afford at the time (June 1997), in today's money it would have cost around €150. Not too cheap, and I think the internals show good quality construction. I'll let the photos do the talking.It's not yet CAT-rated and input protection seems minimal. There are beefy HRC fuses, though. I also quite like how they dealt with the 9 V battery, nice terminals directly on the pcb and the battery itself is placed inside a plastic sleeve that's a snug fit and then held in place by a little ridge in the back of the housing.The whole layout clearly shows some thought went into this unit, and though it may look like those cheapo yellow meters, internally, it isn't.It's not the stiffest meter, but it has a really nice selector switch. The feel is really positive with smooth but very clearly defined indents. Measurements are still accurate, I compared the readings last year against a calibrated HP 34401A, and they were still bang on. Screws are Fluke-style selftappers, and like with these meters the threads seem to remain intact.

author: jitter
author_rank: Frequent Contributor
timestamp: May 21, 2016, 10:18:32 am
content: More photos.

author: jitter
author_rank: Frequent Contributor
timestamp: May 21, 2016, 10:24:15 am
content: Another set.

author: jitter
author_rank: Frequent Contributor
timestamp: May 21, 2016, 10:31:22 am
content: Last but not least...When taking this meter apart, I almost lost these little ball bearings that sit on tiny coil springs. That's why this selector switch feels better than a Fluke's...
AD9910 DDS module 420M 1MSPS highest output sampling frequency signal generator - Page 1
Forum section: electronics / testgear

author: splin
author_rank: Frequent Contributor
timestamp: May 18, 2016, 03:15:49 pm
content: Anybody tried one of these or have any thoughts?http://www.ebay.co.uk/itm/AD9910-DDS-module-420M-1MSPS-highest-output-sampling-frequency-signal-generator-/331826021269?hash=item4d425f4395:g:ft4AAOSwJQdXB5XFAt £46 its not expensive but there's b*gger all information in the listing about it.Or what about these 2 channel AD9958 based generators at £54?http://www.ebay.co.uk/itm/AD9958-200MHz-2-Channel-DDS-Signal-Generator-500MSPS-Update-AD9854-ADI-Software-/272234422837?hash=item3f626fa235:g:iZQAAOSw3mpXLAKLOr perhaps the 4 channel AD9959 version for £59?http://www.ebay.co.uk/itm/4-Channel-AD9959-200MHz-DDS-Signal-Generator-500MSPS-Update-AD9854-ADI-Software-/271718275185?hash=item3f43abd871:g:-MYAAOSwqu9VE6nQNone of them are expensive but cheap Chinese test gear (or pretty much anything else) often seem to have some surprising failings/shortcomings/"I just don't believe it" moments.Does anyone know of any (relatively) low cost AD9914 based signal generators?

author: radar_macgyver
author_rank: Frequent Contributor
timestamp: May 20, 2016, 05:57:42 am
content: This barely qualifies as test gear - more of a breakout board. Having said that, the AD9910 is a decent performer, except for near-carrier noise. There was a web page titled "AD9910 sideband noise" but it goes to a 404 now. Martein did some sleuthing and found that the reference voltage for the AD9910's DAC did not have a bypass pin that filtered the noise it produced. This translated, through the DAC, to an increased noise floor. Note that this is not phase noise, it is amplitude modulation of the DAC output by a noisy reference. It's a pity, because the AD9910 is otherwise a great chip. I used its cousin, the AD9957 to build an ARB.
Tektronix DPO3034 Calibration and Signal Path Compensation - Page 1
Forum section: electronics / testgear

author: alper.y
author_rank: Contributor
timestamp: April 26, 2016, 06:37:57 pm
content: Hi,We have couple of DPO3034s lying around in our lab. Scopes are sent to a third party calibration facility regularly. What I have noticed is that there are some scopes that have never performed a SPC (signal path compensation) after leaving the manufacturing factory like since 2011 (nobody really cares SPC) But that scope was calibrated in 2013 and 2015, for example.Is it possible to calibrate scopes without making SPC? I don't know the calibration procedure and couldn't find steps easily. Is facility cheating on us?Thanks.

author: nctnico
author_rank: Super Contributor
timestamp: April 26, 2016, 07:33:10 pm
content: Well if the SPC hasn't drifted outside the specs then there is no need to run it.According to the Websters English dictionary calibration means checking AND adjusting but in test house slang it means checking only.

author: alper.y
author_rank: Contributor
timestamp: May 18, 2016, 05:40:13 pm
content: Well, what I think is that they hook up a test signal to scope channels to see whether it is within specs or not. You don't know status of SPC + calibration, two unknowns are there. How can you sure that both of them (SPC and calibration) are fine? SPC isn't the only error involed in measurement. You don't know the status of calibration too. How can you measure the effect of SPC only? What am I missing here?