A partial collection of my DMM's 
Check out that PROVA 803, with not one but
TWO function knobs, one for each channel! I've never seen that before.
13 is an unlucky number, you should send one to Dave.......
Don't laugh guys, it's all I can afford right now. I am eyeing an Agilent or a Fluke, once I get some income..
It says it's automotive, but that's just because it has an inductor for spark plug wires to show RPM's and dwell angles. It actually works decent, compared to a friends fluke, it was actually pretty spot on which surprised me. But for voltages above 600v, I wouldn't trust it. It says CAT II 600v, then says it handle 750v AC and 1000v DC? Um, ok.. lol
Well, I just ordered a Fluke 87V.
Been wanting one for a few years and after being spoiled in the Air Force, always having a Fluke in my tool box. Now I need to find an affordable Hall Effect DC ammeter clamp.
I'll post a pic when it arrives.
Great choice sir. Out of the large number of flukes that I have I have never bought an 87v yet. It's on my list tho...
Here is most of my collection, there's also a cheap analog meter that I'm not sure even works anymore that I am not including and I'm sure if I look hard enough I'll find at least one more.
I've had the Fluke the longest, it was old when I got it, 12 years ago or so, it's been well (ab)used.
Two differential voltmeters: the Fluke 887A (AC/DC) and Fluke 895A (DC only).
Both are specified at 25ppm accuracy on DC ranges. The difference is the 895A has infinite input impedance at balance on all ranges, whereas the 887A presents 10M input impedance on the 100V and 1000V ranges.
The pictures demonstrate the difference. The 895A (on the right) is measuring a 10V voltage source directly. The 887A (on the left) is measuring the same voltage source, but in series with a nominal 10M resistor.
On the 10V range, they measure the same (well, 10.00035 on the 887A and 10.00000 on the 895A -- that's as close as I could match them during calibration).
On the 100V range, however, the 887A reads 4.9978 -- it's neatly divided the voltage in half with the 10M series resistor.
This thread is quite interesting indeed. Some truly amazing pieces of equipment out there, and it's nice to see lots of it still in service too!
It's funny seeing the juxtaposition of vintage Flukes and Keithleys amongst dime-a-dozen chinese specials, too!
Those are two interesting pieces of equiptment. I assume you have them referenced to an external source, or do they have their own intetnal one. Is the ac/dc a thermal rms converter.
Those are two interesting pieces of equiptment. I assume you have them referenced to an external source, or do they have their own intetnal one. Is the ac/dc a thermal rms converter.
Both contain temp-compensated zener diodes for internal reference voltages. The DC-only version has inputs on the back so you can connect an external reference to the KV divider inside. The AC/DC version is average responding. There's yet another model (the 931A/B) that measures RMS using a thermal converter.
All of these are plentiful on eBay, with gigantic price gaps between the clean/tested ones and the junky ones that need a bath and a tune up.
I guess it's about time I made a contribution to this thread. I won't bore you with the gray-and-yellow meters around here. But here are some items from Mr. Modemhead's Multimeter Museum.
Back row: Weston 7320, Weston 6100 "Roadrunner", Beckman 3020
Front row: Fluke 8020A, Beckman RMS225
All are made in USA circa 1980 except for the RMS225, which is more like 1990-ish. I couldn't afford these when they were new, so they are all recent acquisitions. The 8020A and 3020 required repairs, but all are functional.
... I won't bore you with the gray-and-yellow meters around here.
I wouldn't mind seeing those gray & yellow meters of yours, especially ones with histories where you fixed them.
What's with the Weston? Looks just like the Fluke. Great condition. They all look like they were made yesterday!
What's with the Weston? Looks just like the Fluke.
I asked Dave Taylor (drtaylor) who originated that side pushbutton design and he was of the opinion that Fluke did. The Weston is no cheap clone though.
Take a look inside. Awesome hand-drawn PCB layout. When I hold it to my ear I hear disco music.
I wouldn't mind seeing those gray & yellow meters of yours, especially ones with histories where you fixed them.
I made a little gray and yellow sculpture for you. A few needed repairs, but a bottle of IPA and some fusible resistors takes care of most problems. I fibbed earlier, I did save my pennies and buy the leftmost 87 around 1990. With an updated LCD and white backlight, it's still my favorite meter.
Excellent to see your contribution to this thread Mr Modemhead.
*snip
That is rather interesting, I forgot that average responding voltmeters can be that accurate by themselves. Then I remembered that they were almost neck and neck with your average thermal rms converter in a high end multimeter(70/80's vintage.) It is rather interesting that it seems like they used a possibly dual matched diode for this. To bad I cannot find any information on the diodes. My average responding voltmeter (Ballantine 323-07) utilizes 2 matched back diode(unitunnnel) true rf stuff these days.
I wouldn't mind seeing those gray & yellow meters of yours, especially ones with histories where you fixed them.
I made a little gray and yellow sculpture for you. A few needed repairs, but a bottle of IPA and some fusible resistors takes care of most problems. I fibbed earlier, I did save my pennies and buy the leftmost 87 around 1990. With an updated LCD and white backlight, it's still my favorite meter.
Thanks for the DMM artwork.
Are they all bought used and broken ? Really, from the photo, they're all look so bling & shiny.
Fusible resistors ? Whats that for ?
Just the stacked-up ones (and the second 87) in that shot were advertised as 'broken', but when half of them end up only having dead batteries, it's not too much of an achievement to get them going again.
And the ones that look the least abused physically always have the best odds of success, no surprise there.
Fusible resistors open up when too much power is dissipated, preventing further damage. You will find at least one in just about every Fluke design.
I know for sure who to consult 1st, when I scored a cheap, heavily abused & broken Fluke meter in the future.
I know for sure who to consult 1st, when I scored a cheap, heavily abused & broken Fluke meter in the future.
Just don't pay $150 USD + $35 s/h from this seller
http://www.ebay.com/itm/321254188871PS. It probably has one of the worst descriptions as well.
I have an old kinzo 18D26 that i use in "sacrificial" mode (is that huge cap discharged, yeah lets see...)
Mastech MS8230B El cheapo - ebay
MD10759 - another cheapo but works great and very accurate in low ranges
See Pics for the other meter
Might be time to get the other one calibrated