I know that meter.... HPIB... GPIB... IEEE488B. I wrote device drivers for it and a HPBASIC, C and ATLAS interpreters/compilers...
IMHO, its biggest strength is programmability... we used them in ATE racks to write test sequences for metrology, production, etc... Properly calibrated they were very reliable, consistent (repeatable ) and accurate. Note that part.... "calibrated". For accuracy we had to calibrate all of our equipment. ALL of it. So, I don't know how accurate a 7 digit DMM will be without calibration.
Sure, I have three modern 4 and 5 digit handhelds... but I still have one of these... and the fascinating thing is this is one of the very few things I have never smoked!
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Actually for tube equipment maintance a vintage HP 410C is well suited: 100 Meg input 1500v max 15mV full scale min. AC to 700 MHz and 500V to .5V. Its 1% and analog meter so not high precision but well suited to tube work. A lot were sold. I have worked up a pcb that replaces all the active circuitry with modern parts so repair doesn't need to be too hard.
If you really want to measure 1KV then you need high voltage probes and an arc flash suit. There is a YouTube video about a tech who died in an arc-flash incident because he tried to measure 2KV with a handheld meter. https://steelgripinc.com/arc-flash/...2c4770e42ce132a7be81f5ab3317664&gclsrc=3p.ds&
I just spent $20 at Harbor freight on a meter because it measures capacitors up to 10mF (10,000uF). Now that is useful. If it happens to be only 5% accurate, I could care less but I'm sure it's good for at least 1%.
I just spent $20 at Harbor freight on a meter because it measures capacitors up to 10mF (10,000uF). Now that is useful. If it happens to be only 5% accurate, I could care less but I'm sure it's good for at least 1%.
Measuring 1 kV safely strongly depends on the possible power that can be delivered. There is a difference measuring a tube amplifier or a distribution transformer. Also knowledge and education on the do’s and don'ts are essential.
In energy distribution handheld DMMs as used for hobby are normally not used to measure high voltages.
Bought this one that was made in 1965 last week for 1 Euro. For audio having expensive lab quality instruments will not make designs better, it is correct interpretation of what is measured that counts.
In energy distribution handheld DMMs as used for hobby are normally not used to measure high voltages.
Bought this one that was made in 1965 last week for 1 Euro. For audio having expensive lab quality instruments will not make designs better, it is correct interpretation of what is measured that counts.
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You can always purchase a used Heathkit, Eico or RCA VTVM -- they will do 1kV, 1.5kV. I am still using an Eico 222 I purchased as a kit in high school!
Fluke 45- It looks to be a great service bench meter. Pleanty of accuracy- response to 100 KHz, dual display (a possibly very useful feature). On eBay for around $100.00. For service work you could do much worse. https://accusrc.com/uploads/datasheets/3944_45.pdf
Good info, good lab instrument. OP has one. Just make sure to find a replacement VFD with it as they usually are close to 30 years old.
A Uni-T UT8803E may not have dual displays but it is brand new, affordable and the display is very clear. Good ergonomics.
A Uni-T UT8803E may not have dual displays but it is brand new, affordable and the display is very clear. Good ergonomics.
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Interesting... it has a USB port.
I wonder, can it be programmed?
Using C or even Python, if you had a number of such devices you could actually write some test procedures. You know... input a signal and measure an output.
Buying a 6 1/2 digit meter is the thin end of the wedge. It's worthwhile if you're going to do serious R&D where the accuracy of your measurements matters. After buying a pair of 34410A (you need at least two meters for any serious experiment), you then realise you need decent power supplies. Then a good LCR meter. An arbitrary function generator. Perhaps an electrometer. Perhaps an RF generator. A sourcemeter. Some more DMMs. Computer control. And how do you make all those things you're going to test? You'll need a pillar drill, a lathe, and perhaps a mill. Maybe even two of each to deal with little stuff and bigger stuff. And somewhere to put all this kit. What with one thing and another, your 4 3/4 digit handheld DMM will do just fine. Not trying to put you off, just pointing out where the road leads.
LOL, I'm on that road. I just picked up my 3rd lab linear P/S. You can never have too many. And I still use a DIY SMPS with a fixed +-15/+5 sometimes. Two scopes now too. You can never have too many channels. My 1st was a 2 chan, my second is a 4 chan, and I often slave them together using the Ext Trigger to see 6 channels at trigger time. A perilous expensive road.
The big programable HP power supplies in the early 80s had a means to abort the output. The input data registers all got latched to 1 and then to 0... very fast.
But not fast enough to prevent a very short full power spike with hundreds of volts and a nuke power plant bunch of current.
It wasn't bad enough that I smoked the board's control circuits with reversed polarity 69V @3A... but when I jumped and hit the Big Red Abort Power Button on the front of the test set, every power supply on the test set ( five or six of them.... 4U and 5U... ) sent a spike that not only blew most of the TTL and analog electronics on the board but also fried the logic and signal processing circuitry in the ITA.
The guys who designed the test set didn't read the whole programmer's guide on those power supplies.
It was quite an event.
I'm quite good at finding corner cases that other people never thought about...
At least the failure happened in our R&D lab, not after shipping to the customer. So, I got a promotion, raise and six months of paperwork from the safety guys.
( Funny, how it was all guys... ).