Looking For Usable Multimeter - Cheap
William Sommerwerck wrote:
This discussion reminds me of the article on digital voltmeters in
"Electronics World" about 50 years ago.
Back then, they were huge, taking up (if I recall correctly) a 3U or 4U
space. The meter they described was a Non-Linear Systems model. Its ADC was
electromechanical, (!) using a relay-controlled voltage divider on a
highly-accurate voltage source to create successively closer approximations
to the input voltage.
There were no commercial LED displays, of course, so the results were
displayed using incandescent lamps to side-illuminate numbers cut into
polycarbonate blocks! (I don't know why NLS didn't use Nixie tubes.)
HP made a voltmeter plugin for their 5245L frequency counter. That
was mid '60s vintage.
--
You can't fix stupid. You can't even put a band-aid on it, because it's
Teflon coated.
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