hybridfree/eevblog-posts huggingface dataset:
Great rip off is Aussie spirit - Page 1
Forum section: electronics / testgear

author: nukie
author_rank: Frequent Contributor
timestamp: May 24, 2013, 05:42:56 am
content: This is 2013 prices extracted from the Australia National Measurement Institute for calibration services. Yes I know they run a Josephson standard but $1500 base charge for a Multimeter Calibration?! It makes Agilent calibration services look like a bargain now!The NMI DC capability is indeed impressiveWith least uncertainties of measurement of -(0.2 uV/V + 10 nV) to (2.8 uV/V + 200 nV) up to 1100 Vvs AgilentWith least uncertainties of measurement of10 uV/V + 0.4 uV from 1 uV to 0.22 V6 uV/V from 0.22 V to 2.2 V5 uV/V from 2.2 V to 22 V8 uV/V from 22 V to 1000 Vhttp://www.measurement.gov.au/Services/calibrationtesting/Pages/LowFrequencyElectricalandMagneticQuantities.aspx

author: ConKbot
author_rank: Super Contributor
timestamp: May 24, 2013, 07:21:25 am
content: almost $4k from NISThttp://www.nist.gov/calibrations/voltage.cfmBesides, who do you think Agilent goes to?They spend big money for traceability to the big standard, and everyone else sends stuff to them to get their traceability though Agilent, and eventually the end user gets the sticker on his DMM from the plant cal lab...

author: mzzj
author_rank: Super Contributor
timestamp: May 27, 2013, 06:43:06 am
content: Roughly same price as Finland's national measurement standards lab.National Measurement Labs are at the top of the food chain. They are not interested to calibrate your average fluke 179 handheld, there are other services(Like Agilent) for that.When you need to calibrate your HP/Agilent 3458A that 1500 $AU is not that bad. Besides, getting accredited calibration for 8½ digit multimeter even from Agilent is pretty much same price level as Aus. NMI.

author: EEVblog
author_rank: Unknown
timestamp: May 27, 2013, 07:19:50 am
content: Quote from: mzzj on May 27, 2013, 06:43:06 amYes, and their prices reflect.Their are not in the volume calibration market.QuoteA 3458A would be the minimum you'd consider sending to NMI. They usually do the gold standard and reference calibrators for the other cal labs.

author: Unknown
author_rank: Unknown
timestamp: May 27, 2013, 07:23:33 am
content: Can Agilent AU do a full cal on a 3458a? Last time I checked (a couple of years ago), only their Loveland facility had that ability.

author: EEVblog
author_rank: Unknown
timestamp: May 27, 2013, 07:58:59 am
content: Quote from: alm on May 27, 2013, 07:23:33 amI recall them saying they could, but don't quote me on that.Test uncertainty ratio would be small, and would likely require much beard stroking and metrology hand waving.
When to use Low-Z mode on meter? - Page 1
Forum section: electronics / testgear

author: rwgast_lowlevellogicdesin
author_rank: Frequent Contributor
timestamp: May 27, 2013, 06:52:33 pm
content: The other day I bought a klein MM200 which turned out to be broken, so I took it back and exchanged it for an MM2000, which I really pleased with, the accuracy is great!I just set up a 4.096 v reference to test the meter, then I added a 1k/51k 1% resistor divider to test the meters mV capability (it is advertised as only going down to 400mV) , This should generate 78.7mV, my meter read 78.8 so I'm pretty happy with that! But then I switched it over to Low Impedance mode and it read around 62mV. I know Low-Z is helpful to eliminate ghost voltage on mains, but is there any time it should be used in electronics?

author: PA0PBZ
author_rank: Super Contributor
timestamp: May 27, 2013, 07:03:04 pm
content: Ghost voltage is not only seen with mains, you can have the same in low voltage electronics due to capacitive coupling between the wires. A low impedance mode will take care of that. But I agree, it is not used a lot.

author: metalphreak
author_rank: Frequent Contributor
timestamp: May 28, 2013, 12:58:54 pm
content: Low impedance mode means the resistance across the inputs of the multimeter are lower. Couple this with the rather high resistance voltage divider and it's easy to see why you get a lower value.From the manual:Input Impedance (Nominal): > 10M?, < 100pFInput Impedance (Low-Z): > 3k?, < 200pF, up to 600V RMSInstead of 10Mohm in parallel with the 1k resistor (negligible effect) you now have 3k in parallel. Now you have 750ohms of parallel equivalent resistance in series with the 51k resistor. Assuming all the values are 100% accurate (resistor and input impedence given) you'd get a measurement of ~59.36mV.(didn't really answer your question, and you might have known the above, but I felt like sharing for others)
New HIOKI DMMs available, DT4281, DT4282 - Page 1
Forum section: electronics / testgear

author: zaoka
author_rank: Frequent Contributor
timestamp: December 06, 2012, 09:08:53 pm
content: Quotehttp://www.hioki.com/newproduct/DT428182/DT428182_e.html

author: zaoka
author_rank: Frequent Contributor
timestamp: January 02, 2013, 04:19:40 am
content: They release a new video (Japanese).... check out angle view for display...DT4281, DT4282??

author: Shuggsy
author_rank: Regular Contributor
timestamp: January 02, 2013, 06:23:18 am
content: Looks pretty good. I'd like to see Dave put it through its paces with his voltage standard and Keithly current sources then take the thing canyoning...

author: SeanB
author_rank: Super Contributor
timestamp: January 02, 2013, 06:42:20 am
content: Impressive, nice viewing angle, but a little gimmicky with the covers. Not much use if the leads are already in there.....Otherwise I like the AC with DC offset readings, very useful indeed.

author: dr_p
author_rank: Frequent Contributor
timestamp: January 02, 2013, 02:08:00 pm
content: Well, you can't switch to that range untill you unplug the leads. It seems like a good idea to me.

author: ilikepez
author_rank: Regular Contributor
timestamp: January 04, 2013, 05:43:22 am
content: Price isn't too bad either, if its similar quality to a US made Fluke.

author: EEVblog
author_rank: Unknown
timestamp: January 04, 2013, 07:39:24 am
content: Quote from: Shuggsy on January 02, 2013, 06:23:18 amThey are welcome to send me one!Dave.

author: EEVblog
author_rank: Unknown
timestamp: January 04, 2013, 07:48:28 am
content: 0.05% + 5 on DC current is very impressive. Fluke 289 class specs.Dave.

author: ve7xen
author_rank: Super Contributor
timestamp: January 04, 2013, 08:02:01 am
content: Quote from: SeanB on January 02, 2013, 06:42:20 amMy early 90s-vintage HP 974A uses a pretty much identical scheme to protect you from trying to measure voltage with the probe in the current jack. When I first got it I thought it was pretty clever, and it's the only meter I've seen it on (until now). I think I prefer the modern solution of bleating at you, as my brain seems incapable of remembering whether you have to turn the dial first or move the jacks first. It does a good job at what it's meant for though - no blown fuses yet!

author: EEVblog
author_rank: Unknown
timestamp: January 04, 2013, 08:07:08 am
content: Quote from: ve7xen on January 04, 2013, 08:02:01 amGossen have had shutter protection for decades.Dave.

author: retiredcaps
author_rank: Super Contributor
timestamp: January 04, 2013, 08:27:29 am
content: The cheap Fluke 17B $20 lookalikes (YH112) have them as well.http://www.ebay.com/itm/330746556287If it was free shipping, I would consider ordering one for teardown.

author: zaoka
author_rank: Frequent Contributor
timestamp: May 27, 2013, 02:34:19 am
content: Some new models available:?DT422x?/DT425x??
New Meter, Thermocouple broken? - Page 1
Forum section: electronics / testgear

author: rwgast_lowlevellogicdesin
author_rank: Frequent Contributor
timestamp: May 26, 2013, 02:00:49 am
content: So I have had my eye on an extech 530 as my main meter for a while, but yesterday I went to home depot and picked up a Klein MM200 for about $50 bucks to use as a secondary meter when accuracy isn't as important. The major reason I bought this thing is because I am working on a digital solder station and I needed something capable of reading 1000 degrees +.Last night is the first time I used the meter, I noticed the func button looked a little faded but everything else was packaged very nice, so I don't believe it was a return. The meter works just fine so far, except on the temperature setting... I plugged the thermocouple in so its negative prong was in the COM jack and its positive was in the V/uA/nA jack. The problem is the thing always reads in the 70's with or with out the thermocouple plugged in. I compared the temp reading to a .5% DS18B12 (i think thats the model) sensor, and it was only a few degrees off. I then stuck the tip of the Tcouple under my tongue no change, and just now I touched the shaft of a 30 Watt iron and still got a 77 degree reading. Does it sound like the meter/thermocouple may be faulty or is there something I am missing? I've never had a meter that did temp before, I tried hitting function on the temp setting, but it did nothing.

author: Rerouter
author_rank: Super Contributor
timestamp: May 26, 2013, 02:22:08 am
content: it soulds like the input to the meter is dodgy, that or the thermocouple is open circuit,to test this, leave your probes in instead of a thermocouple and short them together it sould dramatically change the reading, if it does not its the meter input,
Solmon SL20 mod and teardown - Page 1
Forum section: electronics / testgear

author: Alana
author_rank: Frequent Contributor
timestamp: May 25, 2013, 07:53:00 pm
content: Got my hands on some second hand test equipment and parts, including this iron.I played around with it and decided to use it as my main iron, but in order to do it as i like to do it i needed to add a power switch. After i did that i realized that this is old soldering station, entirely analogue and someone here may be interested in what's inside. Pics were taken after i added power switch and from what i can see this unit was already modified by its original owner.Chips are 2x LM339 and one LM324. Power to the heater is controlled by BT136 triac.

author: SeanB
author_rank: Super Contributor
timestamp: May 26, 2013, 06:42:28 am
content: Not exactly old, still available as new ( I have one) and with the spares available cheap, like the complete iron ( fits SL20 and 30) and the transformers and the main board. Somebody took the time to mount it in that case, it comes in a sloped plastic case normally, they cut out the front panel ( where the board sits )and mounted it in the metal case. Only issues you will have are the DIN plug corroding inside with years of use and going intermittent, but a new socket is quite cheap or free if you have an old XT board lying around to take the keyboard connector out of it. In the original white plastic ( mine is now yellow) it has a power switch, though some people leave it on always with no problems. Replacement tips are cheap, got plenty around, and they are cheap new retail by me. Got 2 sitting next to me in a baggie I picked up free a few weeks ago.
Handheld Oscilloscopes - Page 1
Forum section: electronics / testgear

author: WanaGo
author_rank: Regular Contributor
timestamp: May 23, 2013, 11:26:19 pm
content: Hello AllI am looking for a decent handheld oscilloscope, and just wanting to know if anyone has any input of good/bad otherwise.Mainly using it for bench testing, however also for in the car and various things out and about. I know for equivilent money I could get a nice bench scope, however would prefer the portability.I came across the SIGLENT SHS810, and the SIGLENT SHS1102, along with the Hantek DSO1102B and Hantek DSO1202B. There are a few others too.I think I am mainly interested in the SHS810.Anyone know much about them? Good/Bad etc?I found this youtube review, however its in Russian, but it seems to give a fairly good overview on what the unit looks like and displays like:?????? SIGLENT?? SHS800Any input would be appreciated.Thanks

author: WanaGo
author_rank: Regular Contributor
timestamp: May 23, 2013, 11:33:07 pm
content: I also just found Sigilent SHS815 and the Sigilent SHS820, but it seems the SHS820 has less memory depth.http://www.tester.co.uk/downloads/dl/file/id/113/shs800_series_datasheet.pdf

author: rolycat
author_rank: Super Contributor
timestamp: May 24, 2013, 12:31:45 am
content: mikeselectricstuff has a review of the Owon HDS3102M-N here:There's a teardown too:

author: WanaGo
author_rank: Regular Contributor
timestamp: May 24, 2013, 01:26:34 am
content: Thanks,Watching the vids now.Just realised the SIGLENT scopes are quite bad for sample rate with dual channel... hmm.Looking again and I see the Hantek DSO has a BV range which has 1M memory compared to the Kb the B range has. That puts it back in the spotlight for me a bit.Hantek also has a higher screen resolution over the SIGLENT.Will take a look at this Owon one in more detail now.

author: WanaGo
author_rank: Regular Contributor
timestamp: May 28, 2013, 09:38:56 pm
content: Decided to go with a Hantek DSO1152S+LAN option, which is a 150Mhz handheld, 1M Memory, 1GS/s etc, Isolated inputs to GND and between channels.Will see how it goes when it arrives.

author: rf-loop
author_rank: Super Contributor
timestamp: May 29, 2013, 09:06:51 am
content: Quote from: WanaGo on May 24, 2013, 01:26:34 amCan you explain this your changed thruth....As far as I know 60, 100 and 150MHz models haveFor normal memory, realtime sampleratesmax 1GSa/s for 1 channel with 40k memorymax 500MSa/s for 2 channels with 20k + 20k memoryFor long memorymax 500MSa/s for single channel in use 2Mpoints memory (example Hantek 1M if even it is true)max 500MSa/s for both channels simultaneously and 1M + 1M memory (example hantek 500k+500k)This smaller memory leads to slower samplerate with slower horizontal speeds.what is now "quite bad"?
EL302P output regulation speed test - Page 1
Forum section: electronics / testgear

author: IanB
author_rank: Super Contributor
timestamp: May 05, 2013, 04:21:10 am
content: I was curious about how fast my EL302P power supply can react to sudden load changes and how stable the regulation would be. This was prompted by my observation that when I connect a bulb to the output the current limiting cuts in almost instantly to limit the cold filament surge current. I decided to test this with my oscilloscope to examine more closely what happens.I did the test below with a 12 V 12 W automotive bulb. I set the power supply to regulate at 8 V and 1.5 A and measured the current with a 1 ohm series resistor in circuit with the bulb.For test #1 I switched the power supply on first to regulate at 8 V and then connected the bulb. For test #2 I used the same circuit but I used the output on/off switch on the power supply instead of an external switch.Test #1: Connecting load to power supply with output already onWe can see here a momentary overshoot of the current to about 3 A before recovering to the regulated 1.5 A. The overshoot spike has a duration of less than 500 µs and is caused by the discharge of the output capacitor on the power supply. Once the capacitor has discharged the current regulation is immediate and stable at the set value.The voltage climbs as the bulb filament warms up until the power supply switches over to voltage regulation once the filament is hot enough to limit the current.Test #2: Using the output switch on the power supply with the load already connectedThis time we see that the current is well controlled with no overshoot. When using the power supply's own output switch it electronically ramps up the output voltage at a measured rate and introduces voltage or current regulation as soon as either set point is reached (in this case the current).This shows the benefit of having a purpose designed output on/off switch on a laboratory power supply. Since all power supplies have some capacitance on the output for improved voltage regulation you are always at risk of a current spike if you suddenly short the output of the power supply while it is switched on.

author: icon
author_rank: Regular Contributor
timestamp: May 24, 2013, 03:29:30 pm
content: Quote from: Paul Price on May 24, 2013, 02:04:30 pmYou've given me a lot to think about.John

author: IanB
author_rank: Super Contributor
timestamp: May 24, 2013, 03:34:30 pm
content: Quote from: Paul Price on May 24, 2013, 02:04:30 pmIt's an illustration of a regulatory control problem. In this other thread, you can see how the makers of a different power supply completely failed to design an effective solution to the same problem:https://www.eevblog.com/forum/testgear/comparing-two-power-supplies/

author: Paul Price
author_rank: Super Contributor
timestamp: May 24, 2013, 06:46:08 pm
content: Ianb,A Beautiful Presentation,Thank you for explaining the purpose of your presentation.Information like this can really help beginners and even remind experienced engineers how power supplies should and do work.
Who said you can't play with a scope? - Page 1
Forum section: electronics / testgear

author: madires
author_rank: Super Contributor
timestamp: May 24, 2013, 09:03:10 pm
content: Just the audio output is missing :-)

author: Hydrawerk
author_rank: Super Contributor
timestamp: May 24, 2013, 09:18:20 pm
content: That's possible on every scope with Windows... Nothing special.You have probably seen this or similar video.Tetris on HP 54603B:http://www.stream.cz/uservideo/446115-tajna-vestavena-hra-v-osciloskopu-hp-54603bAsteroids on Agilent 54624A:http://www.stream.cz/uservideo/575185-akcni-strilecka-hra-skryta-v-osciloskopuHow to launch the Asteroids on Agilent 54624A:http://www.stream.cz/uservideo/575187-jak-spustit-akcni-strilecku-v-osciloskopuThere are even those jumping letters on Agilent scopes, but that's not a game at all. Everyone has seen it. And then there is an Etch-A-Scope in DSOX2000 and DSOX3000. I have tried it on my DSOX2000, only one printscreen was made. No video yet!https://www.eevblog.com/forum/reviews/my-new-toy-%29-agilent-dsox2002a-sex-on-a-stick!/?action=dlattach;attach=44113;image
Janatek Annie-USB (500MHz LA)...Clearance - Page 1
Forum section: electronics / testgear

author: JimmyMz
author_rank: Regular Contributor
timestamp: May 23, 2013, 11:54:54 pm
content: Here is the linkhttp://www.tequipment.net/JanatekANNIE-USB.htmlThe cost is only 35% of the list price...which means 65% off, and quite a great deal.Some notes and a link to the product's homepage-----------------------------------------------------------Beside offering 8 channels, the Annie USB has a 3K memory buffer available for each channel if sampling rate is 500MHz, but at sampling rates 200MHz and below, a full 1 Meg memory buffer (per channel) is utilized. The Annie USB also offers triggering (1, 0, X-don't care) on all of the eight channels, and a 8 bit pattern generator.I know it's not the Intronix LogicPort (32 channels), but it does offer 1Mb of memory per channel at 200MHz and below sampling rates, and that's terrific. I'm not quite sure of the compression used on Janatek's offering, but I'm fully aware Intronix uses a wonderful algorithm to make up for the 2K memory buffer, so let's try to not turn this topic into a "Intronix is so much better thread." This thread is for those looking for a great deal on a quality logic analyzer, and lets try to be happy for those that could use the cost savings. Friendly discussion is of course encouraged! Here is a link to the manufacturer's informationhttp://www.janatek.co.nz/janatek_nz/ms/la/annie-usb.htmlPersonally, I have been searching for a capable Logic Analyzer at a great price point, so I just bought this device. Another great coincidence is that the retailer making this offering is tequipment, whom I consider a solid dealer, and I honestly can't say enough good things about them...this deal just proves why I find them so lovable. I hope this clearance sale helps at least one forum member out, if it does, then this topic was successful.

author: JimmyMz
author_rank: Regular Contributor
timestamp: May 24, 2013, 03:00:49 am
content: They went back to full price within 3 hours. I hope that means someone bought one.
Issues with Voltcraft IR 900-30S pyrometer - Page 1
Forum section: electronics / testgear

author: Magnifito
author_rank: Newbie
timestamp: May 23, 2013, 06:33:08 pm
content: Hello!As you may see I'm new here, but I hope to find this forum a good ship for me as I embark on my journey in electronics world.Let's get to the point. I bought in an auction a Voltcraft IR 900-30S pyrometer for less than a half price (~45$ instead ~106$). It was sold as "retourwaren" which as I presume is a german term for equipment returned to the seller. It should be in working order and if it isn't I have 10 days to send it back and get my money back. As it turns out it works really well showing my desk's temperature or my freezer's. I tried to measure my body's temperature and it shows 30 degrees Celsius. I thought "it isn't made for that purpose", but when I measured my oven which should be over 200°C it still showed 30°C, next was my heat gun and boiling kettle and they also were 30°C. The K type thermocouple works perfectly fine, it's the IR measurement that have issues.Should I return it or I'm doing something wrong? I'm well aware of shiny metal objects, spot size vs distance and different emissivity of materials.Here's some basic specification:30:1 opticsTemperature range: -50 to +900°CAdjustable degree of emissionMeasuring range K-type: -50 to + 1370 °CThanks in advance!Edit:I'm not sure if this thread should be in "Test Equipment" or "Other Equipment & Products" so sorry if it's in wrong section!
M4070 LCR Meter - Page 1
Forum section: electronics / testgear

author: rstor22
author_rank: Regular Contributor
timestamp: April 06, 2013, 03:45:34 pm
content: Hello Everyone,I am looking to purchase an L/C meter and originally was thinking of the LC200A (my budget is under $100USD):http://mpl.jp/lc/LC200A%20%20EN%20V5.0.pdfRecently I came accross the M4070 LCR meter:http://kwansnet.dyndns.org:1080/shares/public/User%20Manual/M4070/M4070%20ManualV1_1.pdfWhich seems to be better than the LC200A (see chart at link below):http://www.ebay.com/itm/M4070-AutoRanging-LCR-Meter-Up-to-100H-100mF-20MR-1-accuracy-5-digit-display-/321036981265?pt=LH_DefaultDomain_0&hash=item4abf4b9411I want to get everyone's opnion on the M4070 LCR meter and if it is worth it for the price (approx $60 USD).Thanks!

author: Hydrawerk
author_rank: Super Contributor
timestamp: April 06, 2013, 04:40:27 pm
content: I would never buy it. It is a strange LCR meter. It has too few functions. It is even impossible to manually set the test frequency (1kHz.....100kHz). Never buy unknown products from unknown manufacturers. I recommend the CEM DT-9935 or similar LCR meter, they are all based on the almost same chipset. See this for pros andcons:https://www.eevblog.com/forum/testgear/cheap-lcr-meter-cem-dt-9935/

author: rstor22
author_rank: Regular Contributor
timestamp: April 08, 2013, 07:01:59 pm
content: Thanks for the feedback Hydrawerk. At the moment I really only needed a capacitance meter so I ended up purchasing a BK Precision 820 for $15, similar to the following:http://crownassets.pwgsc.gc.ca/lotImages/FS173573.JPEGI'll hold off on the LCR meter until I am ready to purchase a proper one.

author: Hydrawerk
author_rank: Super Contributor
timestamp: April 10, 2013, 02:58:18 pm
content: Why not, most LCR meters will not work up to 1000mF capacity.

author: pmaggi
author_rank: Contributor
timestamp: May 13, 2013, 02:20:25 pm
content: I've recently bought this lcr meter. I've played around a bit with it and it seems to work ok. All the components that I have measured with it are within the specified error.Although is a bit bigger than I expected and it looks a bit "chinese", it works.For only $49.99, you can´t go wrong

author: ekwan1970
author_rank: Newbie
timestamp: May 23, 2013, 10:19:38 am
content: I also bought this one, because the review is good.http://www.jestineyong.com/review-of-jingyan-m6013-autoranging-capacitor-tester/

author: N TYPE
author_rank: Regular Contributor
timestamp: May 23, 2013, 12:59:26 pm
content: Jestine Yong is a boss when it comes to SMPS repair
B&K Precision 2810 - Page 1
Forum section: electronics / testgear

author: (In)Sanity
author_rank: Regular Contributor
timestamp: May 21, 2013, 03:29:59 am
content: So over the weekend I scored (?) one B&K Precision 2810 meter dated 1978 for around $2.The crazy part is it's still spot on accurate on all range, DC, AC, Ohms, Current. On DC and AC it's within 1 digit, ohms is just a couple digits out and current not far behind. It actually rounds up at the right spot on DC volts vs my 3457A.I can't find a thing about this meter anywhere. Does anyone have any documents for it, specs, etc..etc ? Yes I'm a bit of a B&K fan. I guess I should have got my fluke 8050A in the picture as well as the meter on the Tektronix 2465BDM and let's not forget the Harbor Freight POSThanks,Jeff
Voltcraft VDO-2152A scope firmware (= GDS-1152A-U) - Page 1
Forum section: electronics / testgear

author: harm
author_rank: Contributor
timestamp: May 21, 2013, 02:02:14 pm
content: I've aVoltcraft VDO-2152Ascope with corrupted firmware. So I'm looking for update firmware file for this scope.I thnk it's the same asGW Instek GDS-1152A-U.Any help will be appreciated.Thanks!Harm
Using 2 scopes for 4 channel measurement - Page 1
Forum section: electronics / testgear

author: Harvs
author_rank: Super Contributor
timestamp: May 21, 2013, 02:24:15 pm
content: I picked up my new scope today and thought it was a good time to break out the programming manual.I did some tests feeding the trigger out of the DS2072 into the external trigger and channel 1 of the DS1052, and got a trigger delay of 210ns +/- 5ns across all time bases on both scopes. So I though that wasn't too bad, the trigger delay could be corrected for, so it just leaves the uncertainty over +/-5ns.So I learn't a few SCPI commands (I never realised it was as easy as it is,) and hacked together a quick piece of test software to see if the concept was going to work. I recon it worked ok, and it'll be easy enough to write an SPI decoder for it. The screen shot attached was using a 200kHz SPI bus that's driving a DAC. Both 2nd channels of the two scopes are capturing the same clock signal to show the channel alignment.

author: free_electron
author_rank: Super Contributor
timestamp: May 21, 2013, 02:54:51 pm
content: yep. that works fine. i used to do that with two 54645d's. that gave me 4 analog and 32 digital channels. ideal to debug a huge fpga.i had the fpga actually generate a trigger signal and both scopes looked at that. zero delay

author: marmad
author_rank: Super Contributor
timestamp: May 21, 2013, 02:55:36 pm
content: Quote from: Harvs on May 21, 2013, 02:24:15 pmThere's a mini-discussion of the Trigger Out at the Rigol DS2000 thread(starting here). BTW, the trigger delay when using the External Trigger is slightly less: ~163ns +/- 4ns (of jitter) - see image showing 8x 250ps jitter.These delay times (~160 and 210ns) are not very good, IMO, and rather a disappointment of the DS2000. I think a typical Trigger Out delay should be closer to 50ns maximum - and certainly with less jitter.
Why do some multimeters have dedicated mV ranges? - Page 1
Forum section: electronics / testgear

author: Robomeds
author_rank: Frequent Contributor
timestamp: May 18, 2013, 05:55:51 pm
content: I was looking at a Fluke 73iii I own and started thinking, why does it have a dedicated 300mV range? I can understand why someone might want to measure a low voltage. I'm not questioning the desire to measure sub 300mV ranges but really, why can't/isn't this incorporated into the autoranging DC voltage range? Is there a significant change in input impedance in the mV range?Incidentally I have seen this on several of my non-Fluke meters as well.

author: Monkeh
author_rank: Super Contributor
timestamp: May 18, 2013, 06:11:58 pm
content: Quote from: Robomeds on May 18, 2013, 05:55:51 pmOnly about 2.99GOhm, typically.

author: Robomeds
author_rank: Frequent Contributor
timestamp: May 18, 2013, 06:36:19 pm
content: gigaohms.... hmmmm....

author: Monkeh
author_rank: Super Contributor
timestamp: May 18, 2013, 06:40:05 pm
content: Your Fluke seems to be 10M on mV, though. Pays to check the specs..Not sure why it has a separate range for the same impedance.

author: Robomeds
author_rank: Frequent Contributor
timestamp: May 18, 2013, 06:50:34 pm
content: Well the 87-iii and 73-iii show the same impedance in both the mV and V settings according to Fluke. However, I do see that if I start the meter in high impedance mode the 400mV range does gain 3.99 Gohms of impedance. By default the 87-iii has only 10Mohm resistance in either DC volts range. That could explain why the 87 has such a range but not the 73-iii which doesn't have a high impedance setting.

author: ModemHead
author_rank: Frequent Contributor
timestamp: May 18, 2013, 06:52:17 pm
content: On Fluke auto-ranging DMMs, there is usually a 10Meg resistor in series with the input, and one of several other grounded precision resistors is switched in by the microprocessor to form a divider for 1:10, 1:100, etc. But for the millivolt range, the 10Meg resistor is grounded, and the ADC input is taken straight off the input jack (1:1) through the ohms sense resistor or through a separate resistor of about 1Meg. The input impedance thus remains at about 10Meg for all ranges.Given this input divider reconfiguration, I suppose it's easier to just have another switch position.
898d+ solder station adjustment - Page 1
Forum section: electronics / testgear

author: kozlojak
author_rank: Contributor
timestamp: May 18, 2013, 05:06:14 pm
content: I have seen people talking on this forum about adjusting the temperature read out on the 898d+ 2 in 1 solder stations, but have not seen any instructions on how to do it. Does anyone know how to do it or can they point me in the right direction?
HP 3456A problem - Page 1
Forum section: electronics / testgear

author: Harvs
author_rank: Super Contributor
timestamp: May 17, 2013, 08:05:11 am
content: I've got a 3456A that I think has a problem, trying to measure a resistance above about 100k is a hopeless exercise.The 3 least significant digits oscillate at about 1Hz. It gets worse the higher the resistance measured, with a 10M resistor it can't hold a value within 1% It also does this to a lesser degree on the voltage ranges.I always figured it was just something I was doing wrong. But I figure if I get a 500k 1% metal film resistor, and clamp it directly into the screw down binding posts, I should reasonably expect that I would make that measurement, or is there something stupid I'm missing here?I remember a thread maybe a year or two back (I can't find it now) which I think Vincent was talking about some caps in them always going bad over time. So I was thinking maybe there's some power supply ripple getting through and putting things out of whack?

author: mikes
author_rank: Regular Contributor
timestamp: May 17, 2013, 10:44:35 am
content: Are you setting it to 100 PLC, and filter on to reduce noise in the measurement?

author: Harvs
author_rank: Super Contributor
timestamp: May 17, 2013, 12:00:54 pm
content: Quote from: mikes on May 17, 2013, 10:44:35 amYep, instability in measurement is still there.My Escort 3146A 5 1/2 digit is solid as a rock measuring the same things, and it should be the lesser meter as I see it.

author: saturation
author_rank: Super Contributor
timestamp: May 17, 2013, 05:44:47 pm
content: I have 3 of these, no issues measuring ohms to any range. Have you run a self diagnostic on the 3456a?

author: Harvs
author_rank: Super Contributor
timestamp: May 18, 2013, 12:44:22 am
content: Yeah don't show anything on the self test.Thanks for that vital piece of info, that yours don't do it. Leads me to a more certain conclusion that there is something a miss.I'll crack the lid and measure some voltages.
Analog oscilloscope problem - Page 1
Forum section: electronics / testgear

author: stev.dk
author_rank: Regular Contributor
timestamp: May 16, 2013, 05:58:06 am
content: On normal working mode (real time mode?), theres no problem. When i press the store button, an insane amount of noise is displayed on the screen. On a square wave or a static signal (like 5v), im able to remove most of the noise (almost all noise left, is when the signal changes) using the pot for setting the vertical position, and the balance trim pot. Even tapping the pot seems to make a difference. At some positions the signal is present, but overloaded with noise - at other positions, theres nothing but noise.Sometimes when im trimming the pots, it seems like the whole display is flickering, so a noise peak, that was present 50ms ago, is now gone and visa versa (a clean signal 50ms ago, suddenly have noise).So i think it might be the signal coming from the store function to the display, that is somehow getting contaminated. Does this sound legal, or did any of you guys have a simular problem, that was caused by something else?The scope is a gould os-1420, theres a user/service manual here:http://www.mr2.net/marknias/gould1420.pdfPlease note, theres nothing wrong with the probes or the input signals.

author: stev.dk
author_rank: Regular Contributor
timestamp: May 17, 2013, 09:25:01 pm
content: Ok so this is wierd...I took the cover off, and put the scope on its side to make some measurements. I only got around to measure one voltage line, and the problem vanished. Without putting the cover back on, i turned it on its right orientation, and the problem came back. I once again put it on it's side, and again it was working perfectly. Slowly turning it to it's right orientation... and it still works.I havn't been able to reproduce the problem since, but im sure it will return eventually - anyway i put the thing back together. Im waiting for my new multimeter to arrive, so i can do a "service" on the thing.... At least as far as the manual goes, and do some further checking for intermittence.

author: madires
author_rank: Super Contributor
timestamp: May 17, 2013, 09:35:23 pm
content: Bad solder joint?

author: PaulAm
author_rank: Frequent Contributor
timestamp: May 17, 2013, 09:54:40 pm
content: I'm not familiar with that scope, but I had a problem that appeared only when tapping the scope. Finally tracked that down to a cracked ceramic substrate resistor. Drove me nuts trying to find that one. Try tapping around or freeze spray. Sometimes thermal shock will open an intermittent.
Agilent 4+16 7000 series scope with 3 yr warranty (From Agilent) £2700 - Page 1
Forum section: electronics / testgear

author: maiakaat
author_rank: Regular Contributor
timestamp: May 17, 2013, 04:24:28 pm
content: http://www.ebay.co.uk/itm/Agilent-PREMIUM-USED-MSO7014B-Mixed-Signal-Oscilloscope-/171040521352?pt=BI_Oscilloscopes&hash=item27d2cf3c88I thought I'd post this, way more than I could or would pay for at my level

author: ben_r_
author_rank: Frequent Contributor
timestamp: May 17, 2013, 05:39:10 pm
content: Most of us around here know about this already. They will even accept MUCH lower if you make them an offer!
Is this old Scope DVM-638 multitester a repackaged Fluke? - Page 1
Forum section: electronics / testgear

author: rvmeush
author_rank: Contributor
timestamp: May 18, 2013, 07:52:19 pm
content: I have an old Scope multitester that looks very similar to some old Fluke meters such as the 8020B. Can anyone tell me if this Scope meter is really a repackaged Fluke, and if so what model? Thanks.

author: Lightages
author_rank: Unknown
timestamp: May 18, 2013, 07:56:48 pm
content: Many companies copied the Fluke look. This is one of them. Another tell tale sign that this has nothing to do with anything Fluke is that it has a transistor tester.

author: Fsck
author_rank: Super Contributor
timestamp: May 18, 2013, 07:58:10 pm
content: Quote from: Lightages on May 18, 2013, 07:56:48 pmit also has a capacitor discharger!

author: free_electron
author_rank: Super Contributor
timestamp: May 18, 2013, 08:37:44 pm
content: I had one of those as a kid. Mine was a hung-chang. It also had the slanted top around the display like the flukes had

author: mariush
author_rank: Super Contributor
timestamp: May 18, 2013, 08:38:09 pm
content: I don't see it. The text says "discharge capacitor before connecting", you probably only looked on one side.My guess is that it's a clone.

author: Fsck
author_rank: Super Contributor
timestamp: May 18, 2013, 08:49:17 pm
content: Quote from: mariush on May 18, 2013, 08:38:09 pmyeah, sleep deprivation wreaks havoc on my attention span. I've never actually seen a DMM with special capacitor slots, ever.
BK Precision 4040A vs Rigol DG1022/A and DG4062  - Page 1
Forum section: electronics / testgear

author: Electro Fan
author_rank: Super Contributor
timestamp: May 17, 2013, 09:08:33 am
content: Does anyone have any experience with the BK4040A? I think the 4040A might hold it's own against the 1022/A but maybe not so much vs. the 4062. Thoughts? Thankshttp://www.bkprecision.com/products/signal-generators/4040A-20-mhz-sweep-function-generator.html
MSOX-2024a WavGen - Page 1
Forum section: electronics / testgear

author: jstarr
author_rank: Regular Contributor
timestamp: May 15, 2013, 03:52:33 am
content: I have to send off my scope for service as the holdoff doesn't seem to be working correctly. Before doing so I want to get an opinion if the WavGen option is working less than expected.The MSOX2024a Wavgen with square wave at anything from 5 -10 Mhz seems to lose the 5th harmonic. I have compared to an external square wave source (Rigol AWG) - in the attached picture - Channel 1 is the Rigol AWG and Channel 2 is the MSOX2024a WavGen. Shouldn't the MSOX Wavgen have some better odd harmonic characteristics?

author: DRT
author_rank: Regular Contributor
timestamp: May 15, 2013, 10:39:36 am
content: No, it looks about right. The Wavegen output has a rise time of around 19ns - see this thread for a similar discussion on the 3000 series Wavegenhttps://www.eevblog.com/forum/blog/new-agilent-scopes/msg229832/#msg229832

author: ben_r_
author_rank: Frequent Contributor
timestamp: May 15, 2013, 03:16:32 pm
content: Wow... Seems kinda slow. Makes me happy I didnt sink the $500 into the WaveGen upgrade and put that money into a real Agilent arb waveform gen.

author: jstarr
author_rank: Regular Contributor
timestamp: May 15, 2013, 06:18:32 pm
content: I was disappointed as well. I would have updated to the new Riogol 4000 series instead. I assume there is no way these software licenses can be sold or transferred?j

author: ben_r_
author_rank: Frequent Contributor
timestamp: May 15, 2013, 06:25:04 pm
content: Quote from: jstarr on May 15, 2013, 06:18:32 pmNope, they are tied to the specific units serial number.

author: Hydrawerk
author_rank: Super Contributor
timestamp: May 15, 2013, 07:57:24 pm
content: The MSOX2024a Wavgen hasprobably100Msamples/sec. The Rigol AWG micht be better. Which model did you use?
ADXL345 spike value - Page 1
Forum section: electronics / testgear

author: eminempark
author_rank: Newbie
timestamp: May 16, 2013, 09:18:29 am
content: I would like to ask why in the sensed data that I have, it has a spike value. For example:(x y z)(0.027 0.988 -0.113)(0.035 0.988 -0.125)(-2 0 -1.004)(0.035 0.984 -0.125)(0.035 0.984 -0.125)For your information, i'm using accelerometer ADXL345 sensor. Why it can be happened?

author: ConnorGames
author_rank: Regular Contributor
timestamp: May 16, 2013, 10:32:59 pm
content: Do you have a scope? If so, check that the power supply and the i2c lines are nice and clean. I have also found these chips quite sensitive to inadequate decoupling. Make sure there is at least a few uF of ceramic capacitance as close as possible to the supply pins. On my 9dof stick from sparkfun, adding a 10uf ceramic in parallel with the existing .1uF dropped the noise floor to 1/4 of it's previous value.I am assuming the code you are using is not at fault, but make sure to try some example code from the web if you are not doing so already.Good luck!
Interesting chips you have seen - Page 1
Forum section: electronics / testgear

author: SeanB
author_rank: Super Contributor
timestamp: May 16, 2013, 05:05:40 pm
content: While stripping an old Playstation the other day I found this interesting gem hidden inside the optical drive. Unusual in that it has all the optics of both the laser and the photodetector in one package, all on multichip modules with as well the photodiode amplifier. All that is outside the package is the diffraction grating/mirror and the focus and tracking lens assembly, all on a nice die moulded and machined zinc alloy casting.The rest is common, aside from the massive thermal pad between the 2 heatsinks and the processor and support chips. Even covers the memory chips but they are not cooled by the heatsink. Power supply only has a single 12V rail that it provides.Anybody got interesting chip pictures you want to share here?
Siemens S 43205-M-A (TV-Antennen-Messprozessor) - Page 1
Forum section: electronics / testgear

author: ddrl46
author_rank: Regular Contributor
timestamp: May 14, 2013, 08:03:29 pm
content: I've had this device for about a year and managed to get it more or less working but I haven't been able to find any information about it on the internet. I wonder if anyone on this forum knows what it is or has any documentation on it.

author: vk6zgo
author_rank: Super Contributor
timestamp: May 15, 2013, 02:14:57 am
content: I'm pretty sure it is a Signal Strength Meter for adjusting "free to air" TV receiving antennas & distribution systems.The raster display is probably for displaying analog TV pictures.Even if you don't have analog TV anymore,the signal strength part should still be useful,depending on the tuning range.

author: Fraser
author_rank: Super Contributor
timestamp: May 15, 2013, 10:33:41 am
content: I can confirm that it is an analogue terrestrial TV signal analyser. I have a similar unit from the same manufacturer. Its quite a beast and not exactly portable ! I believe my unit was used to monitor signal quality rather than to align aerials. Its driven by an 8bit microprocessor and my unit refuses to boot correctly. The large MEMCAP had leaked on the CPU board.I translated the front panel using Google translate and that helped workout the various functions.I have yet to find any documentation on these units but then I have not looked that hard. I bought it on a whim and it is so much larger than my other TV signal meters that I doubt I will ever use it.

author: ddrl46
author_rank: Regular Contributor
timestamp: May 15, 2013, 01:22:31 pm
content: Quote from: Aurora on May 15, 2013, 10:33:41 amMy unit is powered by a Motorola MC6800 and the memory backup batteries have also leaked, luckily those were on a separate card. I'm not sure if it's actually doing what it's supposed to do since pretty much all the buttons do the same thing (make the number on the front count up to 57.36 and make the screen display two black bars as seen in the third image) and become unresponsive after that (maybe something to do with the card with the batteries).This one also came with a battery pack that bolted onto the back and contained 6 2v lead acid batteries (which are of course dead).Could you post pictures of your unit?
LCR Meter: Extech LCR200 vs BK Precision 879B - Page 1
Forum section: electronics / testgear

author: mathsquid
author_rank: Frequent Contributor
timestamp: May 13, 2013, 09:19:08 pm
content: I want to buy an LCR meter that is capable of measuring ESR, and these are the two models I'm considering. I would probably go for the BK Precision 879B over the Extech LCR200 except for one thing. The extech will measure ESR at 100kHz while the BK only goes up to 10KHz. I read that 100kHz is the standard frequency that ESR is typically measured at, but I'm not really sure how important that is. Can someone give me some guidance on this?Thanks in advance,M.S.

author: PA4TIM
author_rank: Super Contributor
timestamp: May 14, 2013, 11:42:57 pm
content: http://www.pa4tim.nl/?p=3775must give you enough info to make a desiscion.
Uni-T ut61E - Page 1
Forum section: electronics / testgear

author: Unknown
author_rank: Unknown
timestamp: May 14, 2013, 09:55:29 am
content: I have a Uni-T ut671 E, which I like kind of, however I'm not happy with the software, I bought it as I wanted a data logger multimeter, the software is crap, it won't work with windows 7, when I install it , it states ports 1,2,3,4, yet install the software and I get ports 7,8,9,10, I don't even have these on the computer which has 1,2,3,4 so I emailed Uni- T, asking them for the fix ,or proper software, been 2 months not a dickie from them, customer service from Uni-T is crap, so ut61e is going on e-bay, to be replaced with a Gosson Metrowatt.The one thing I really hate is bad customer service.

author: iloveelectronics
author_rank: Frequent Contributor
timestamp: May 14, 2013, 10:05:23 am
content: Quote from: Telequipment on May 14, 2013, 09:55:29 amDo a search for UltraDMM here. A forum member wrote this software and it supports the UT61E.

author: Unknown
author_rank: Unknown
timestamp: May 14, 2013, 11:29:12 am
content: Ok thank you

author: Wytnucls
author_rank: Super Contributor
timestamp: May 14, 2013, 12:05:35 pm
content: The UT61E logging software is not great, but it installs and runs fine on my Win7 machine.
Power Supply Calibration? - Page 1
Forum section: electronics / testgear

author: somlioy
author_rank: Regular Contributor
timestamp: May 13, 2013, 02:37:29 pm
content: HiI had to repair my E3644 and now it needs a calibration. I dont fancy sending this heavy beast away, so I'd prefer do to it my self.So the question is how could I calibrate this to get it close to its specs? I'm considering buying a bench meter (3478 or 3457). With either of those the voltage part should be ok?What about the current part? Could a homebuilt dummy load do or is it prefered to use a proper programable electronic dc load? Service manual suggest a 0.01ohm , 0.01% shunt tho, which I dont have.

author: babysitter
author_rank: Frequent Contributor
timestamp: May 13, 2013, 03:24:57 pm
content: Either calibrate it against your own multimeter, or look out for another electronics guy in your neighbourhood. Maybe go doorbell ringing to the next tv repair shop.GreetingsHendrik
Need DSO/MSO That Has Dual Time base - Which Do you Recommend? - Page 1
Forum section: electronics / testgear

author: jstarr
author_rank: Regular Contributor
timestamp: May 13, 2013, 03:32:28 am
content: My Rigol MSO 1102D can be set for two different horizontal settings on Ch1 and Ch2 and two very different signals can be triggered and viewed simultaneously. I would like to get a new 200 Mhz scope with similar capability, more measurement features, bigger screen.... can someone recommend one?thanksj

author: Hydrawerk
author_rank: Super Contributor
timestamp: May 13, 2013, 02:49:14 pm
content: GW Instek GDS-2000A has alt trigger, but probably not independent horizontal controls.https://www.eevblog.com/forum/testgear/gds-2000a-new-economic-oscilloscope-by-gw-instek-comes-to-market/If you want a scope with real independent four channels, you can buy the expensive GDS-3000.Well, the scope is not perfect. It was never popular among hobbyists. It has only 25kpoints memory per each channel.Then some Siglent might have independent trigger and horizontal setting per each channel, but that scopes are not much better than your Rigol DS1000, they are quite basic.