hybridfree/eevblog-posts huggingface dataset:
measuring rectified SCR clipped AC serial capacitor, true RMS ac+dc or? - Page 1
Forum section: electronics / testgear

author: Redeeman
author_rank: Contributor
timestamp: June 28, 2015, 10:06:33 pm
content: Hello.I am going to be measuring on a system where 230VAC is fed into an SCR, and then from there onto a bridge rectifier, where the load will be serially connected with an AC motor run capacitors for current limiting (around 140-150uf).what i wish to measure is both the voltage and amperage draw, and i guess both before and after the scr+bridge rectifier.i saw this:https://www.eevblog.com/forum/testgear/a-look-at-the-uni-t-ut210e/and ordered this, given its cheap price, as all I have now is pretty much one of those $5 cheap chinese meters (which back then cost $15 in my local store).would this ut210e be able to accurately measure the current draw both before the SCR and perhaps after the rectifier aswell?and then for measuring voltage, since (i hope) i will be able to use the ut210e clamped on to measure current, i will need a meter to measure voltage. I was thinking of getting the brymen 257 as it seems to be a solid unit, and im done with unsafe cheap chunk(i assume the ut210e clamp one is safe on the count of clamping instead of probes)but then i noticed, only true RMS on the AC side. so would this give me issues here?to be honest im not even fully certain how the waveforms are going to look with the capacitor in serial like that, and with the SCR clipping before the rectifier, but as i understand it, true RMS would be applicable to DC too, and in the case where for example three phases are rectified so theres always a DC offset and some AC ripple (or if it was a single phase with smoothening capacitor parallel connected?), right?but in this case, theres only one phase being rectified in a bridge, so would this be "taken care of" with true rms AC mode? or does the serially connected capacitors do something to this?Thank you all very much in advance

author: tautech
author_rank: Super Contributor
timestamp: June 30, 2015, 11:20:31 am
content: Welcome to the forum.Tell us some more.Is the SCR just used as a switch or for phase angle control?You say the load is capacitively coupled through motor run caps, correct?What is the load?

author: Redeeman
author_rank: Contributor
timestamp: July 02, 2015, 12:49:20 am
content: the SCR is used to clip the AC voltage to reduce it, it is one of those 230VAC in, 0-230VAC out type of things.And im afraid i wrote wrong before, the motor run capacitors are to be placed on the AC side, so this would probably make sense to put before the SCR.the load is resistive to my understanding, it is going to be an HHO cell, with a huge load of steel plates to conduct current through water.
Fixing my "new" tektronix 7L12 spectrum analyzer - Page 1
Forum section: electronics / testgear

author: harrimansat
author_rank: Regular Contributor
timestamp: June 30, 2015, 06:19:01 pm
content: One taltalium cap shorted:

author: Rupunzell
author_rank: Frequent Contributor
timestamp: July 01, 2015, 07:19:59 am
content: Good..Suggest replacing the other Tantalum caps before they explode too. Problems with the Tantalum caps in Tek stuff is quite common.Bernice
Velleman DVM9912 Teardown - Page 1
Forum section: electronics / testgear

author: dumle29
author_rank: Regular Contributor
timestamp: June 30, 2015, 01:34:48 am
content: Hello there. I've considered shipping dave a Velleman DVM9912 for a teardown, but I don't have 100$ + shipping to spend on that. Therefor I decided to take it appart myself, and try and take some proper pictures with whatever lighting I have.First of all, the specs of the meter:http://www.velleman.eu/products/view/?country=be&lang=en&id=368124I'm not entirely sure what more to write, so I will link in an album that I posted on imgur, as I prefer that for image hosting. Do note that most pictures will have a small description under them.Album:http://imgur.com/a/YD8QmEDIT: And a note on the lack of background lighting of the LCD, I can't seem to find any Velleman DVMs that use that PCB, which has the backlight. Velleman is a reseller of other OEMs though, so the original OEM might have a different version that Velleman decided not to rebrand and sell.

author: Vgkid
author_rank: Super Contributor
timestamp: June 30, 2015, 01:58:33 am
content: Thanks for the teardown. It is always nice to get a mini review with a teardown.

author: retiredcaps
author_rank: Super Contributor
timestamp: June 30, 2015, 05:14:36 am
content: Quote from: dumle29 on June 30, 2015, 01:34:48 amThanks for taking the pictures and sharing.CEM Instruments is the original OEM for this multimeter.http://www.cem-instruments.com/en/pro/sort7-1.html

author: Hydrawerk
author_rank: Super Contributor
timestamp: June 30, 2015, 12:21:26 pm
content: In a CEM multimeter I expected some better fuses for .But for low voltage bench use it might be OK.But the construction is definitely better than my own UNI-T UT70A.

author: dumle29
author_rank: Regular Contributor
timestamp: June 30, 2015, 10:43:37 pm
content: QuoteAhh, thanksQuote from: Hydrawerk on June 30, 2015, 12:21:26 pmThat is certainly my major gripe with this meter :/
using a mouse with a Pragmatic 2414A Arbitray Waveform Generator? - Page 1
Forum section: electronics / testgear

author: Stray Electron
author_rank: Super Contributor
timestamp: July 06, 2015, 03:55:16 pm
content: I picked up a surplus Pragmatic (now Tegam) 2414A AWG and fixed it. I downloaded the manual and read it and it mentions that you can use an "optional" serial mouse to "draw" new waveforms and store them in the 2414. The 2414 has a DB-9 serial port on it so I dug out an old IBM PC compatible mouse and tried using it. It does work but the mouse is overly sensitive and displayed data pointjumpsaround the screen (I have the 2414 output connected to an O'scope and displaying the 2414 input live.)Does anyone know anything about the mouse that's supposed to be used with the 2414? This mouse uses chopper wheels and optical encoders internally I'm also wondering if I can desensitize the mouse by cutting out every other vane in the chopper wheels. Does anyone have any experience doing something like this?

author: daddario
author_rank: Regular Contributor
timestamp: July 06, 2015, 08:25:03 pm
content: You probably can't lower the sensitivity of the mouse by cutting the bars - wheel mice and other rotary encoders rely on the known length of the blank and transparent parts of the wheel. Outputs of two opto pairs are compared and the direction/step count calculated from that data.
I have a fluke  ir3000fc bluetooth interface  - Page 1
Forum section: electronics / testgear

author: firehopper
author_rank: Frequent Contributor
timestamp: April 15, 2015, 03:35:09 pm
content: its used for the android/iphone app. Its really easy to disassemble and I could take some nice high rez photos of the insides I'm sure it could be used for bluetooth pc interface too.

author: firehopper
author_rank: Frequent Contributor
timestamp: April 17, 2015, 03:42:47 pm
content: images follow

author: retiredcaps
author_rank: Super Contributor
timestamp: April 17, 2015, 06:05:58 pm
content: Yes, post pictures please.

author: tmbinc
author_rank: Frequent Contributor
timestamp: April 17, 2015, 06:29:51 pm
content: Yes, I'd be interested, too.

author: firehopper
author_rank: Frequent Contributor
timestamp: April 17, 2015, 08:34:23 pm
content: more images follow

author: firehopper
author_rank: Frequent Contributor
timestamp: April 17, 2015, 08:35:32 pm
content: last set of images

author: MerlinMac
author_rank: Newbie
timestamp: June 30, 2015, 11:11:15 am
content: Hi good morning , today has gone a major application update ... do not hesitate to put it ... greetings
Partly Faulty Fluke 1900A - Page 1
Forum section: electronics / testgear

author: wilhe_jo
author_rank: Regular Contributor
timestamp: June 30, 2015, 07:08:28 pm
content: Hi again!I'm just sitting here and debugging an old Fluke 1900A Counter.Bought this some months ago because it was reasonably cheap, looked ok and was sold as "not working" because of low sensitivity.(give it some cal and it will do I thought....)Some weeks later I shot a Schlumberger dual counter with oven, gpib,... really, really cheap (50euro) ...so that little Fluke found its way to the cellar and waited for fixing...Now I'm at home fore some weeks because a really dumb accident while relocating to my new flat and I needed something todo.That's when I remembered that Fluke counter and searched for it in all that boxes.After a day of debugging I found that that everything was in cal but someone just removed the batteries (that unit had that option).The probelm: Fluke used the NiCads for regulation (!) and buffering.I quickly wired an 7805 up, added some more caps and what should I say, it works with sensitivity within spec (25mV spec, 15mv Typ, after some tweaking I got 12mV ).Well so far so good, 2kHz to 75Mhz works (the unit goes up to 80 but I can only generate up to 75MHz) but below 2kHz something strange happens.The 74LS112 seem to generate some spikes and glitches...Since all that 74-logic was powered from 7.7V (no NiCad-Regulators) I suspect them at least partially faulty but where to start.My guesses are the counters (74LS112+LS00 and 74LS90) but since none of them was socketed, I thought it's better to ask if someone has a better guess...I plan to change them in the following order:LS112 (2- JK FF used as main decade counter in conjunction with the LS00)LS00 (nand)LS90 (ripple counter)LS196 (ripple counter)LS74 (d-ff)LS42 (decoder)7447 (led driver)Interestingly everything works if the LS00 and the LS112 are cooled down...Thank's in advance for your educated guessesHans
Hoyt Radio Rotary Meter  - How to test this portable multimeter? - Page 1
Forum section: electronics / testgear

author: ez24
author_rank: Super Contributor
timestamp: June 28, 2015, 12:49:41 am
content: I have one of these:http://www.radiomuseum.org/r/hoyt_radio_rotary_meter.htmland was wondering what it was for? I guess used on radios? The meter rotates, thus the name rotary. Looking at the main picture, it has three posts on the left and three on the right.The upper large left one is marked " 30 AMPS " on the left side. The smaller middle post reads " 3 AMPS " and the lower small one reads " 30 MIL-V "The upper large right post reads " + ", the smaller middle one reads " 3 VOLTS ", the lower small right one reads " 30 VOLTS"Summary of readings (for posts):30 AMPS + (big posts)3 AMPS 3 VOLTS (small posts)30 MIL_V 30 VOLTS (small posts)I want to test this but I do not want to do something stupid. What throws me is the " + " sign.I have a bench ps that I can control the amps and volts but not near 30 amps. Could I hook up the positive terminal from the power supply to " + " and negative to "3 volts" and turn up the volts to 3 and see what happens. The same for 30 voltsCan I assume " 30 MIL_V" is 30 millivolts ?Hook up the ps and turn up the amps and volts to test amps ?Any ideas on how to test this mulitimeter?thanks

author: radhaz
author_rank: Regular Contributor
timestamp: June 28, 2015, 05:37:11 pm
content: Did you see this?https://books.google.com/books?id=PNgDAAAAMBAJ&pg=PA664&lpg=PA664&dq=Radio+Rotary+Meter&source=bl&ots=t_h0-w2GWz&sig=bmfVukWP56I4BSKf_D5los9CfO8&hl=en&sa=X&ei=6yWQVf3ZMcTZoASi-oX4DA&ved=0CDIQ6AEwAw#v=onepage&q=Radio%20Rotary%20Meter&f=false

author: ez24
author_rank: Super Contributor
timestamp: June 28, 2015, 08:17:40 pm
content: ThanksI did not know that the meter had to be rotated. I thought it was for how it was to be held, it must of had a pointer that is missing. I tried it at 3 and 30 volts and it works and is accurateStrange to hook up a positive lead and move the negative.Probably designed to be hooked up with several wires at the same time and the dial rotated to the different readings. Wished I had a 1926 radio to use it on.Hard to stop reading the Popular Mechanics, I miss those old magazines.
Cheap scopemeter using DSO112 and UT139C - Page 1
Forum section: electronics / testgear

author: ez24
author_rank: Super Contributor
timestamp: June 30, 2015, 08:05:42 pm
content: About $100 for both meters. The meters are held together with a rubber band.Measuring terrible ripple from a buck converter ( 1.2 vpp on 3.3 vdc).The DSO112 agrees with the Rigol, but the Rigol shows a high freq component that does not show up on the DSO112 (due to bandwidth). Both are using alligator clips. Really bummed over the buck, I ordered 5 more before I hooked up to the scopes. Probably will start a post on the buck (a big one with lots of ripple). My small bucks have little ripple.I like the DSO112, I use it more than the Rigol because it is so easy (limited settings). But I am not using it for rockets.
Fluke 8842A Calibration  - Page 1
Forum section: electronics / testgear

author: Aztlanpz
author_rank: Regular Contributor
timestamp: June 25, 2015, 11:16:23 pm
content: I am looking for a place in the USA to get my fluke calibrated at a low price, a calibration certificate is not required.ThanksAztlanpz

author: eas
author_rank: Frequent Contributor
timestamp: June 25, 2015, 11:47:53 pm
content: Quote from: Aztlanpz on June 25, 2015, 11:16:23 pmEveryone has their own definition of "low price," probably best to specify a $ range.

author: Aztlanpz
author_rank: Regular Contributor
timestamp: June 25, 2015, 11:49:50 pm
content: Less then 100 dollars

author: Muxr
author_rank: Super Contributor
timestamp: June 25, 2015, 11:54:23 pm
content: Someone who works for a place posted about doing cal. Here is their price list:http://www.weedonengineering.com/id24.htmllooks like it's $65.Original post:https://www.eevblog.com/forum/beginners/calibration-fluke-87v-what's-the-correct-price/msg373874/#msg373874You could try PMing him but he doesn't look that active.
Keysight 53230A - new formware version 2.05 - Page 1
Forum section: electronics / testgear

author: olepr01@gmail.com
author_rank: Contributor
timestamp: June 25, 2015, 12:52:55 pm
content: Hello, allI have a Keysight 53230A frequency counter, and this morning I decided to upgrade to the latest firmware, version 2.05. This did not go well..1. Installed the upgrade as per the releasen notes onto a USB-stick. The counter shut down after the upgrade, but for some reason did not restart - as it usually does during firmware update..2. I started the counter with the powerbutton, and it came up normally.3. A few seconds after boot, a window with an error message stating that "Powerplay.exe has experienced a serious error and must shut down", or something to that effect. The window is up side down..4. The counter appears to be working normally behind this window, although it is hard to tell, since the window takes up most of the screen.5. I have not found any way to close that window. Reboot, preset, whatever I try it just sits there, upside down.6. The counter does not repond to any commands over ethernet, although it does respond to pings. GPIB untested (for now)Keysight has removed the previous firmware-version from the download-page, so I currently have no way of downgrading..Anyone else experienced this, or something similar?Thanks for any hints!Ole

author: LA7SJA
author_rank: Regular Contributor
timestamp: June 25, 2015, 06:25:50 pm
content: Have you tried the firmware update utility to see if it can connect to the 53230A? If it can connect, try to update the device one more time.Johan-Fredrik

author: olepr01@gmail.com
author_rank: Contributor
timestamp: June 25, 2015, 06:35:33 pm
content: Tried it, did not work. Not over IP, not over GPIB. However, I managed to dig out version 2.02 in an old download-folder, and the downgrade went smooth. So the counter is operational, which is good news since I just got a new FTS-1000A I am currently measuring!I tried upgrading again to 2.05, exactly the same result. Looks like theres a problem with this software version. My 53230A has a fairly low serial number, MY500011xx, so it may be a case of incompatibility with the first counters to come off the assembly line.. Hopefully they can fix it, I'd be pretty pissed off to be left with an aging firmware..

author: LA7SJA
author_rank: Regular Contributor
timestamp: June 25, 2015, 07:52:01 pm
content: Last proposals before calling Keysight support!Turn of antivirus before downloading and unziping the file again on another USB stick, my 34461A and DSO-X2414 are both very picky about the type of memory stick. If non of this works, you have to describe in minute details what you have tried and the results and send to Keysight support. They always answered me in the course of a workday.Johan Fredrik
DSA815 front end input risk - Page 1
Forum section: electronics / testgear

author: dadler
author_rank: Unknown
timestamp: June 26, 2015, 09:17:27 pm
content: Hi all-I have a DSA815-TG.I also recently picked up the tekbox near field probes that Dave semi-reviewed in a mailbag segment:http://www.tekbox.net/test-equipment/tbps01-emc-near-field-probes-tbwa2-wideband-amplifierI have the TBWA2/40db set with the 40db amplifier.Is there any risk in connecting these directly up to (with or without the amplifier) the front-end of the DSA815?I have a full-set of mini-circuits 2W attenuators, but would prefer to not use them unless necessary.I ask because I've seen a few posts recently mentioning things like static electricity frying the front-end of SA's. The DSA815 has a blocking cap on the frontend, but I don't know if that ameliorates most of the risk in this context.I also had one of the near field probes hooked up through the 40db amplifier, and I was trying to demodulate FM radio into the headphone jack (just for fun). The DSA818 would sporadically report "412 DA overrange due to volume adjustment in FM.". I have no idea what this error means, and I couldn't find any references to it on the web. Hope it doesn't mean I broke something.I know essentially nothing about RF and bought the DSA815 mainly as a learning tool, so be gentle (if possible).Thanks,Dustin

author: Farley
author_rank: Regular Contributor
timestamp: June 26, 2015, 10:06:55 pm
content: The maximum input level is noted just underneath the RF input connector on the DSA815. There it states that the maximum input level is +20dBm. You do not want to exceed that specification.

author: dadler
author_rank: Unknown
timestamp: June 27, 2015, 01:58:10 am
content: Sure, that's the max power level. It also states max 50v DC. I'm going to assume the power rating is for all power/frequencies, not just those measured by the SA. Without a power meter I don't see how I can truly know if I am overdriving the input of the SA.Aurora posted in another thread recently that he felt static electricity could fry the front-end of SAs.I'm not so sure about this, so I started this thread.
Case for Rigol MSO1xxxx  - Page 1
Forum section: electronics / testgear

author: jrmymllr
author_rank: Regular Contributor
timestamp: June 25, 2015, 11:30:37 am
content: I just got an MSO1xxx scope and am looking for a good carrying case. My previous scope, a Tek TDS2xxxx, had it's own case that fit really well. Upon reading the reviews of Rigol's case, I decided to find my own. There's always Pelican, but I don't need anything that rugged. Just something to store it in and maybe put in my trunk once in a a blue moon.Anybody find something good?

author: ebastler
author_rank: Super Contributor
timestamp: June 25, 2015, 02:49:08 pm
content: There is a thread with a few suggestions here:https://www.eevblog.com/forum/testgear/carrying-bag-for-rigol-ds1000z-series-(europe)/

author: jrmymllr
author_rank: Regular Contributor
timestamp: June 25, 2015, 03:43:12 pm
content: Quote from: ebastler on June 25, 2015, 02:49:08 pmGreat thanks, didn't find that one.
EMCO USBHV. Anyone have one? - Page 1
Forum section: electronics / testgear

author: eas
author_rank: Frequent Contributor
timestamp: June 25, 2015, 06:23:43 pm
content: While pursuing the folly of a high-voltage transfer reference for testing a stack of used 5.5 and 6.5 digit DMMs I've acquired, I came across aninteresting device called the USBHV from EMCO High Voltage(self-link). It's a USB powered and controlled high-voltage power source. It looks like it pairs one EMCOs HV modules with a USB DAC/ADC to provide, depending on the model, up to 2000V @ 1W, of positive or negative voltage.I foundone on ebayfor $395. That's too rich for my blood, but it does make me curious. Do any of you have one of these? How's the software? How about programmability?
New FLIR ONE - Page 1
Forum section: electronics / testgear

author: Chanc3
author_rank: Frequent Contributor
timestamp: June 25, 2015, 12:17:08 pm
content: Looks like FLIR have released their new FLIR ONE, however I cannot seem to find any specs on the resolution, although it looks like it's still using the Lepton core (80x60) and MSX to produce a reasonable interpretable image.http://www.flir.co.uk/flirone/Available for iOS now at £199Taking pre-orders for Android!Might actually pick one up now I have the new iPad Mini

author: Chanc3
author_rank: Frequent Contributor
timestamp: June 25, 2015, 12:17:51 pm
content: Just seen Mike's post on new products - please delete!
Sharp LCD for SL Giant Gecko - Page 1
Forum section: electronics / testgear

author: alin_im
author_rank: Regular Contributor
timestamp: June 27, 2015, 06:05:27 pm
content: Hi guysDo you know were I can find the Sharp LCD module for the Silicon Labs Giant Gecko platform like the one in Dave's videoDo you think I can buy them or I need to buy only the LCD and make an adapter, if so where I can find the LCD it self.https://www.youtube.com/watch?t=1464&v=wH6tRrPgaK831:35
Fused probe? - Page 1
Forum section: electronics / testgear

author: dadler
author_rank: Unknown
timestamp: June 22, 2015, 12:45:38 am
content: Hi all-I bought a grab bag of miscellaneous leads and adapters on eBay (there is another set left, if anyone wants it:http://www.ebay.com/itm/Test-Accessories-by-Hirschmann-Multi-Contact-leads-probe-adapters-tweezers-/291476947731)Included in the set is what seems to be a fused probe of some sort. It's marked HCK 500v. Seems too low voltage to really be a high voltage probe?Anyone have details on what this particular probe is? I've never seen one like it before.
Tenma 72-6644 function generator DB9 connector question - Page 1
Forum section: electronics / testgear

author: bubba198
author_rank: Contributor
timestamp: June 21, 2015, 06:48:23 pm
content: Hi everyone,I've had this analog Tenma 72-6644 function generator for years and just now wanted to figure out the DB9 connector however although I do have the user manual, it doesn't explain anything about the DB9 connector pin-outs and what software I need?If anyone is familiar with the Tenma 72-6644 function generator can you share with me some info about how to use its serial port?Thank you~B
AWG Amplifiers - Page 1
Forum section: electronics / testgear

author: Unknown
author_rank: Unknown
timestamp: June 23, 2015, 08:22:09 am
content: Does anybody have any recommendations for a waveform generator amplifier? Most AWGs (built into oscilloscopes at least) seem to only have fairly low signal level outputs, but I have on occasion needed to be able to replay a stored signal at the original signal levels with either decent current drive or higher voltages. About the only reasonably priced thing I've found is a Rigol PA1011, most other solutions seem to cost a fortune, or should I say more than I would be prepared to spend on a piece of gear I wouldn't use often. I don't own I rogol scope, but it looks like this amp can be setup via usb and used with anything. Anybody have an experience with this or other amplifiers?

author: tautech
author_rank: Super Contributor
timestamp: June 23, 2015, 10:14:24 am
content: Recently added new Siglent AWG power amphttp://siglentamerica.com/prodcut-fjxx.aspx?fjid=1289&id=-1&tid=16&T=1RRP USD389 plus taxes if any

author: w2aew
author_rank: Super Contributor
timestamp: June 23, 2015, 01:18:41 pm
content: What peak-peak voltage levels are you looking for?

author: Unknown
author_rank: Unknown
timestamp: June 23, 2015, 10:16:00 pm
content: 15V p-p would be perfect.That Siglent thing looks like it would suit my needs perfectly. Thanks

author: Lightages
author_rank: Unknown
timestamp: June 23, 2015, 11:08:14 pm
content: I have a couple of questions.#1. It has an input impedance of 15kohms. That means you might need to use a 50ohm pass through terminator if you want waveform fidelity when coming from the waveform generator. Why would they not include this simple thing as a selectable input impedance?#2. It also has a very low output impedance, again no 50ohm selectable.QuoteWhat are the implications for using this where a 50ohm source is preferred?And one point to consider; its bandwidth is only 1MHz.
My experiences with 6.5 DMM(8846A,34461A  and 8808A - Page 1
Forum section: electronics / testgear

author: commie
author_rank: Frequent Contributor
timestamp: June 19, 2015, 05:07:54 pm
content: Hi Folks,About 4 years ago I bought a Fluke 8846A, good meter but the dot matrix vfdisplay was absolute crap, after about 31/2 years use the display started to go flat.With the display test feature it was possible to see the 'burn', not long after I decided to Ebay it and that was the end of that.Next I bought a Keysight 34461A, and thought it was the dogs bollocks, I liked it so much I bought another and somewhere in between I bought a Fluke 8808A(5.5 meter)Just recently I was reading somewhere that it's nice to have dual readings on the same meter, so how about the 34461A? You can measure ACI and DCI or ACV and DCV but you can't measure volts and current simultaneously. With the Fluke8808A you can, which I find very usefull.Although I had a negative experience with the Fluke 8846A, the 8808A is one good meter
Leader 1100 analog oscilloscope - Page 1
Forum section: electronics / testgear

author: Fureedo
author_rank: Newbie
timestamp: June 20, 2015, 07:02:47 am
content: Howdy!I got this scope on a classified ad.I think I found out by myself how most of it works, but I'd like to find a manual, some info about the 3rd channel, which, from what I can find, can be used as...well, a third channel in addition to an external trigger, or even just how old it (might) be. Google isn't giving me ANY information! it's like this scope never existed!...or existed before arpanet, who knows? I know it sat in a closet for almost 20 years at least...

author: tautech
author_rank: Super Contributor
timestamp: June 20, 2015, 09:12:33 am
content: Welcome to the forum.Wasn't that hard....about 2 minutes....http://www.ebaman.com/index.php/remository/ELECTRONICS/Test-Equipment/LEADER/Model-1100-Oscilloscope-Operation-Manual/You'll need to sign up to download, do so they're a good crowd, in 10 years I've received no spam, nothing at all from them.

author: Fureedo
author_rank: Newbie
timestamp: June 20, 2015, 05:59:14 pm
content: Cool!Thanks a bunch. I think I see how I failed at googling too.

author: tautech
author_rank: Super Contributor
timestamp: June 20, 2015, 08:26:57 pm
content: Quote from: Fureedo on June 20, 2015, 05:59:14 pmNo you didn't, IIRC it only produced a broken link.So I checked a couple of my favourite manual links and ebaman had it.Here's a thread with heaps:https://www.eevblog.com/forum/repair/repair-documents-and-links-sticky-me-please-mods/

author: Electro Fan
author_rank: Super Contributor
timestamp: June 20, 2015, 10:41:41 pm
content: Quote from: Fureedo on June 20, 2015, 07:02:47 amCongratulations! Looks like you found a particularly nice Leader model. Enjoy!
Rigol DM3058 DMM? - Page 1
Forum section: electronics / testgear

author: aadamson
author_rank: Newbie
timestamp: June 19, 2015, 02:28:22 am
content: I have a brand new DM3058... Just plugged it in, with no probes connected to it, in it's default turn on mode (which for FREQ is 200mV). When I select the FREQ button, it seems to read the AC voltage frequency that it's plugged into. If I raise the scale to 2V or 20V or higher, then it goes to ------- as you would expect.Wondering if others with this unit can verify this on theirs? It seems strange that it would read the line voltage frequency. I put probes on it and that didn't change. I momentarily went to ------, but then returned to read the plugged in line frequency.I went through the documentation and couldn't find any reference to this being what it would do. And I'm puzzled.Thanks in advance, and if you have one and can verify, I would appreciate it,Alan

author: acbern
author_rank: Frequent Contributor
timestamp: June 19, 2015, 06:14:43 am
content: It is picking up ac noise which is the line frequency. short the inputs in the 200mv range and it should go away.

author: aadamson
author_rank: Newbie
timestamp: June 19, 2015, 12:33:03 pm
content: Quote from: acbern on June 19, 2015, 06:14:43 amYes, it does. I'm just wondering if this is normal functioning?Thanks for the response,Alan

author: aadamson
author_rank: Newbie
timestamp: June 19, 2015, 04:26:47 pm
content: I called Rigol US this morning to ask about this... They pulled a unit from their lab while I was on the phone and verified that it did the same thing. On fresh power up, in the defaul 200mV scale, with no probes or with probes connected, but not attached to anything, it seems to read the AC Line voltage that is powering the unit.Hope this helps the next person with this same question... Nice to know my AC is that stable I suppose ...Alan
Logic Record/Playback - Page 1
Forum section: electronics / testgear

author: mtechmatt
author_rank: Regular Contributor
timestamp: June 18, 2015, 11:41:20 am
content: Chaps,After a tool to record logic (like a Salae, or any logic anayliser, BUT also PLAY BACK those same signals.Its for remote development, I need to record the signal patterns from a device (a sensor on an engine) and my friend needs to be able to be send said file, load them into his device, and play them back, easily.Lots of devices can record logic, and lots can play it, even those claim to be both recorders AND generators dont have this middle piece of just hitting 'rewind, play'.Any ideas?Or should I just make a basic one on a PIC?Cheetrs

author: jeroen79
author_rank: Frequent Contributor
timestamp: June 18, 2015, 03:32:51 pm
content: QuoteYou could do that.Add a clock (an order of magnitude faster than whatever you want to record) and monitor the logic channels you are interested in.Whenever the logic channels goes high or low an interrupt is calledThen you write the channelID, state and clockcount to your storage.This will keep storagerequirements low as you only record when the signal changes instead of continuously sampling it.Playback is done by resetting the clock and then testing if the clockcount is matches the recorded count of the next record.When that is true you set the state to the recorded state and move on to the next record.And consider input protection.
De Ree DE-5000 in circuit - Page 1
Forum section: electronics / testgear

author: 944longdrift
author_rank: Newbie
timestamp: May 05, 2015, 05:31:50 pm
content: Hi,Ive done lots of googling but cant find the answer to my question which is pretty simple:Can I use a De ree DE-5000 for measuring ESR in circuit?I've thinking about buying a Peak ESR meter but it seems for less money I can get the De Ree which id much rather have if it can do the same job (and more).I know the Peak's ESR test voltage is around 40mV which makes it good for in circuit but I just cant find this info for the De-ree.Any help would be appreciatedthx

author: daneck
author_rank: Contributor
timestamp: May 05, 2015, 06:44:29 pm
content: I have a DER EE DE-5000 and did the following test on a new nominal 1000 micro farad electrolytic:DMM measured (DC) capacity as 1065 micro faradDE-5000 measured capacity as 961 micro faradDE-5000 measured ESR as 0.15 ohmScope shows 48mV peak-to-peak on the ringing ESR test pulseThus, although specs say "Test signal level is 0.5Vrms typical", it was really only about 50mV, at least for the cap used.I have successfully measured ESR (identified bad, high ESR caps) in-circuit for non-problem configurations (no parallel caps or Shottkey devices)Hope this helps!

author: Shock
author_rank: Super Contributor
timestamp: May 05, 2015, 07:22:45 pm
content: It's spelt DER EE DE-5000.As mentioned previously on the forums (somewhere) the DER EE testing voltage is higher but under application this is loaded down to a semi conductor friendly level. Now if this occurs under all situations, that would have to be tested.The DER EE will not discharge capacitors, the Peak only has limited voltage discharging (it's rated at 50V and under). The DER EE will be almost certainly damaged earlier than the Peak.The DER EE has a slew of features the Peak doesn't including kelvin connectors for lowish ohm measurements. PC interface. Dissipation factor, Quality factor or Phase angle for L/C measurement mode. Data Hold. Tolerance and sorting. Dual display with bar graph. Relative function. DC resistance, AC resistance.The Peak tests at 100kHz. The DER EE has the option of 1kHz, 10kHz, 100kHz, 100Hz & 120Hz. The test frequency can make a big difference in the results.

author: 944longdrift
author_rank: Newbie
timestamp: May 06, 2015, 10:55:26 am
content: Thanks for the replies guys, that's a great help!I really wanted to go with the Der ee and thats given me some reassurance.Even though I had a reply from Der ee themselves saying it's not suitable for in circuit, I guess they're probably covering themselves for all scenarios.They also mentioned the test signal is a sine wave (I believe the Peak uses a square wave). Not sure how much difference it really makes but thought it may be worth mentioning for benefit of others.

author: jtronix
author_rank: Regular Contributor
timestamp: June 17, 2015, 04:25:40 pm
content: have you buy and tried DE-5000 for in circuit testing?

author: Lightages
author_rank: Unknown
timestamp: June 17, 2015, 04:27:52 pm
content: You got that answer already in your thread about the Mastech!
Edit: DSOX2000/3000 UART testsignal has 8O1 parity not 8N1 - Page 1
Forum section: electronics / testgear

author: Pinkus
author_rank: Frequent Contributor
timestamp: June 18, 2015, 07:05:49 am
content: EDIT: I will not change the following as it might help somebody later with the same problem. In short: You should know, that the 19.200 baudUART testsignalsof the scope does not come with "no parity" (as I thought) but "odd parity".Thus there is no bug within the scope - the bug was in front of the scopeHello,by creating my comparison (see here:https://www.eevblog.com/forum/testgear/agilentkeysight-dsox2000a-vs-dsox3000a/msg692627/#msg692627) I found something strange:Can someone with a DSOX2000 or DSOX3000 (or MSOX) please check this if you can reproduce the following. I do not want to report this as a bug if it is none (could be my mistake), however it looks to me, the serial UART decoder does have a bug. You will need serial decoders and training signals enabled on your device.What to do to reproduce:1) Press Help, switch on training signals, select UART.On Pad Demo2 now a 19.200 baud UART signal appears.2) Now connect an analogue probe to pad Demo2 it and start the serial decoder.Settings are 19.200 baud, 8N1,Output in ASCII3) Set trigger type to Serial UART (note: settings were timebase: 1ms, vertical: 1V/div)The decoder should show "KEYSIGHT" but ... every 2nd character is missing and in the lister error frames are shown (see attached pictures "19200 Baud...")Only if you manually select the baud rate18.200baud, the decoding of the 19.200 baud signal works flawless!!(see attached pictures "18200 Baud...")I encountered that in firmware 2.38 and now upgraded to 2.39 and it is still the same.For me, the UART decoder does not work correctly (at least not at 19.200 Baud).Can please confirm this somebody? Please do not tell meIam doing something wrong as that would impair my self-confidenceUsed hardware by me: MSOX3024a with several options (all official), 300 Mhz passive probes.P.S.: as the bitrate measurement is also showing 19.200 baud, I am assuming that the used testsignal is fine - I did not double check yet with UART/RS232 signal from a different source.

author: AndyC_772
author_rank: Super Contributor
timestamp: June 18, 2015, 07:19:12 am
content: On my scope (f/w version 2.35), the demo signal has odd parity. The 8N1 setting is wrong, it should be 8O1.

author: Pinkus
author_rank: Frequent Contributor
timestamp: June 18, 2015, 07:22:54 am
content: Oh my god.... shame shame shame - shame on meI will leave the post online as others might need this too. However I will change the title.Dang!

author: Campus
author_rank: Contributor
timestamp: June 18, 2015, 08:00:31 am
content: Hi,it's working as expected for me as well after changing to odd parity. This is with firmware 2.39.Best,Campus
GPIB Printer capture - Page 1
Forum section: electronics / testgear

author: cncjerry
author_rank: Unknown
timestamp: June 17, 2015, 12:10:48 am
content: I have a device that prints calibration results to a GPIB printer on port 8. I've been coding with Agilent visa using vb.net and couldn't find a way to have the PC look like a GPIB device so that a VB program could act like the printer. I have two-way communications working with any device on the GPIB network using vb.net so that works.Any ideas?

author: VK5RC
author_rank: Unknown
timestamp: June 17, 2015, 01:54:02 am
content: Is ke5fx plotter emulation useful ?http://www.ke5fx.com/gpib/7470.htm

author: TSL
author_rank: Regular Contributor
timestamp: June 17, 2015, 02:40:37 am
content: Besindes the excellent plotter program VK5RC mentioned, if you actually need a printer emulator, use this...http://www.printcapture.com/My HP 54720A only talks to printers over GPIB and that program lets me capture its output. See attached.regardsTim

author: cncjerry
author_rank: Unknown
timestamp: June 17, 2015, 06:40:00 am
content: Thanks for the pointers. I tried the printcapture program and I guess it is picking up the wrong VISA as I have Keysight and TekVisa on this machine. I'll try downloading the NI version and go from there.I keep thinking I should be able to do this with vb.net as it has a listener resource manager but wasn't able to get it working with the limited examples available.I know there is a python version as well but haven't found a link.Thanks again.
Fluke 45 Calibration - Page 1
Forum section: electronics / testgear

author: kalinga
author_rank: Contributor
timestamp: June 16, 2015, 09:53:25 am
content: Hello From Sri Lanka,I have a fluke 45 that's giving an error 7 (calibration needed), i was wondering (as a noob) if its possible to calibrate this myself using already calibrated DMM as a reference ?i did read the fluke 45 service manual but cant seem to make any sense out of it.

author: XFDDesign
author_rank: Frequent Contributor
timestamp: June 16, 2015, 03:42:09 pm
content: According to this:http://bee.mif.pg.gda.pl/ciasteczkowypotwor/Fluke/45.pdfthe error is specifically that the calibration data has become useless. This means that all of the factors used to set the original offset errors and such are junk. To that degree, I would suggest that even supposing you had a 7.5 digit dmm handy you would not be able to have a good calibration to any certainty simply for lack of other available (and known) transfer standards to calibrate against.Also

author: kalinga
author_rank: Contributor
timestamp: June 16, 2015, 04:00:43 pm
content: Thanks! Guess I have to send this to a calibration house.Sent from my Nexus 5 using Tapatalk
Tektronix spare parts. - Page 1
Forum section: electronics / testgear

author: McBryce
author_rank: Super Contributor
timestamp: June 16, 2015, 01:29:35 pm
content: Not sure if this is the right place to post this, if not, feel free to move it.I found this on ebay small adds. The guy is selling off a relatively large stock of unused Tektronix spare parts (late 70's vintage), chips and tubes. I thought it might be of use to some of the Tek restorers here. Too old-school for mehttp://kleinanzeigen.ebay.de/anzeigen/s-anzeige/tektronix-ersatzteile-viele-davon-new-old-stock-/178985620-168-1676?ref=searchhttp://kleinanzeigen.ebay.de/anzeigen/s-anzeige/tektronix-roehren-tubes-ersatzteile-teils-nos-neu-ecc88-/195072559-168-1676?ref=searchMcBryce.
Omni-Directional broadband and Directional Antennas for Spectrum Analyzer - Page 1
Forum section: electronics / testgear

author: crmaris
author_rank: Contributor
timestamp: June 16, 2015, 06:37:24 am
content: Hey guys,Can someone suggest me an Omni and a directional antenna for up to 6 GHz frequency. I want something with decent performance which however won't break the bank. I have noticed the Aaronia ones (OmniLOG 70600 680MHz - 6GHz) and the HyperLOG 7060 (700MHz-6GHz) if anyone has experience with them.Thanks!Aris

author: Howardlong
author_rank: Super Contributor
timestamp: June 16, 2015, 07:18:51 am
content: For directional broadband antennas, Kent Britain is your man. He lives an breathes this stuff.http://www.wa5vjb.com/products1.html

author: Lightages
author_rank: Unknown
timestamp: June 16, 2015, 07:34:47 am
content: Do you really want omnidirectional, as in spherical pattern, or as in cylindrical? For a wide band antenna in a cylindrical pattern you want to consider a discone antenna. At the spread of frequencies you want to look at they are pretty flat across their functional range.

author: crmaris
author_rank: Contributor
timestamp: June 16, 2015, 12:05:50 pm
content: Thanks for your replies!I need an omni antenna to capture and measure wireless streams (including 802.11ac hence I need one above 6 MHz) and a directional one for more specific measurements.So I think a spherical one and not a cylindrical will do.
Looking for a Motorola VP22 motherboard (Pentium III PGA370 815E chipset ) - Page 1
Forum section: electronics / testgear

author: free_electron
author_rank: Super Contributor
timestamp: June 17, 2015, 06:19:38 am
content: I am looking for a :The specialty about this thing :815E based mother boardMicroATX <- mechanically importantCPU is positioned directly behind connectors as opposed to much further down <-mechanically important4PCI slots <- this is the tricky bit. most motherboards are 1 agp 3 pci ... i need 4 PCI....i've ordered some generic motherboards from ebay hoping they will work but those are all 810e based. thise 815e is hard to find.it was made by Motorola ( of all manufaturers ! ) under the product name VP22.don't bother sending me the link to that motherboard shuffler. theyt don;t have any in stock and cannot source them.These motherboards are used in certain agilent machines like 54832D scopes and 1980 logic analysers. They all die becahse the south bridges die. It starts with the loss of peripherals and eventually he pci buss locks up. the fix is to replace the chip ... but i'd rather swap the motherboard.finding the original motorola VP22 board will be almost impossible so the quest is to find a compatible board that can run the PIII 1GHz and runs the scope software without glitches.i am sitting on 3 of these scopes all with the motherboard problem ...integrated intel LAN
UPL calibration - Page 1
Forum section: electronics / testgear

author: acbern
author_rank: Frequent Contributor
timestamp: March 28, 2015, 03:41:40 pm
content: Does anyone here have a calibration- respectively a performance verification procedure for a Rohde & Schwarz UPL audio analyzer?I have aksed RS, and in this case, other than normal, they have not been helpfull at all, did not get anything, not even for sale.Any help or comments appreciated.

author: acbern
author_rank: Frequent Contributor
timestamp: June 20, 2015, 09:20:43 am
content: Nobody out there with owning a UPL? What would already help me is a calibration report, showing what was verified.Thanks
DS Logic - Page 1
Forum section: electronics / testgear

author: wd5gnr
author_rank: Regular Contributor
timestamp: June 15, 2015, 11:26:51 pm
content: I bought a DS Logic off eBay. Good specs. 100MHz on 16 channels with an adjustable threshold. 400Mhz on 4 channels. Custom version of Sigrok.I thought I'd share a few notes (I was going to add them to the Crowdsourced topic, but it was 120 days old so..)On Linux, you DO need to build all the pieces because apparently the stock versions aren't all you need (in particular, libsigrokdecode needed to be the latest).Also, if you don't want to run as root, you need the following in /etc/udev/rules.d/99-dslogic.rules## DSLogic# 2a0e:0001ATTRS{idVendor}=="2a0e", ATTRS{idProduct}=="0003", ENV{ID_MM_DEVICE_IGNORE}="1"ATTRS{idVendor}=="2a0e", ATTRS{idProduct}=="0003", ENV{MTP_NO_PROBE}="1"SUBSYSTEMS=="usb", ATTRS{idVendor}=="2a0e", ATTRS{idProduct}=="0003", GROUP="plugdev", MODE="0660"I have found reference that it could be idProduct is 1, but on mine, it is 3 (I bet 1 is the old one and 3 is the pro). lsusb will tell you. Restart udev or reboot and if you are in the plug dev group you should be ok.Pretty good quality. Not sure the little grounded cables would actually handle anything really going at 400MHz, but honestly a 400MHz LA is only going to go around 200MHz and probably a lot less. So good enough for most of what I do these days.Just to try out 400Mhz, I picked up a serial line and an I2C channel off a demo board.Yeah, 400Mhz is way overkill for this, but it works fine at lower rates too.Not sure why but the search function doesn't appear to work. Probably operator error. Works now for no apparent reason, so apparently operator error.I don't see that the TO pin (trigger out?) works. I also have not tried it with an external clock yet.
Fluke 287(9?) leaking super-cap - Page 1
Forum section: electronics / testgear

author: icon
author_rank: Regular Contributor
timestamp: May 21, 2015, 02:48:21 pm
content: HiI had a look at my 287 a while back, and discovered that, lo and behold, the infamous supercap had spilled its guts.Today, on a whim, I took it into Fluke's UK HQ in Norwich, and had a conversation with a service engineer outside the deliveries door in the back car park - which was a bit odd. He'd never come across the problem, but apparently they don't service hand-held meters there - they're looked after in Eindhoven.Anyway, he took it in, with my details scribbled on a scrap of paper, and promised to get back to me. I hope I see it again one day. If I do, I'll update this thread.John

author: Asmyldof
author_rank: Regular Contributor
timestamp: May 21, 2015, 04:22:14 pm
content: I'll make sure to wave at it while it's "here", make it feel at home a little.

author: dacman
author_rank: Frequent Contributor
timestamp: May 21, 2015, 11:38:47 pm
content: You might be interested in this (mile long) thread:https://www.eevblog.com/forum/testgear/fluke-189-with-leaking-surface-mount-coin-cell/

author: icon
author_rank: Regular Contributor
timestamp: June 13, 2015, 12:06:59 pm
content: Right, so I got my 287 back. The replacement of the leaking supercap was accepted as a warranty issue, which was nice of them, since I'd bought the unit off eBay.Photos attached.John

author: M. András
author_rank: Super Contributor
timestamp: June 13, 2015, 05:20:46 pm
content: there goes the rosh certificatelook the nice new shiny solder. but the quality of it...
antique Voltmeter/Ammeter - Page 1
Forum section: electronics / testgear

author: jpb
author_rank: Super Contributor
timestamp: June 13, 2015, 09:38:24 am
content: As I'm in the process of moving house (I hope) I've been clearing out my loft and came across this very early voltmeter/ammeter.I inherited as a child from some distant relative (he also had a very nice army hat in a special tin box which my brother got - the sort they wore in the 19th century).I thought perhaps a couple of photos might be of interest.