Fun With Vintage Digital Meters!
Added 2019-11-29 02:41:03 +0000 UTCSome fun on Thanksgiving 2019 - taking a look at a couple of really neat digital meters I got from the University of Pennsylvania Haul. One mechanical - one LED - Both digital! Really! Enjoy!
The original video of the U of Penn Haul - https://www.youtube.com/watch?v=_znnfw0tQFc
Comments
Fun! I have quite a bit of vintage test gear (including an old Triplett Model 1200) but no panel mount gear. I always enjoy your demos and teardowns of vintage parts.
Brendan Meteer
2019-12-02 15:43:01 +0000 UTCThose are really awesome!
Jessica McIntosh
2019-11-30 17:31:46 +0000 UTCMechanical pulse counters are still mandated today in some safety-critical applications for the simple reason that they preserve and continue to display their last value when power is removed. In some applications, neither redundant supplies nor a backup battery can provide the required persistence. The only current technology that even comes close is ePaper, and though it has some shortcomings, it is slowly gaining ground in such applications.
BobC
2019-11-30 02:03:52 +0000 UTCA day late, but my Thanksgiving is now complete; Family, Friends, a Thanksgiving Dinner that Can't be Beat, and a Brilliant New Video from FranLab. I love the old stuff, and this was a particular Joy, from the Window in the Styrofoam to the delightful discovery that the that the latter Counter was in reality a Voltmeter! Thank *you* Fran, very much!
2019-11-29 20:18:31 +0000 UTCIt’s great to see you back, Fran. 😊
Nicholas Wilson
2019-11-29 19:16:24 +0000 UTCHappy Thanksgiving Fran x!
2019-11-29 11:13:56 +0000 UTCI bet both of those cost quite a bit back in the day... From a time when displays had a '+' sign as well as a '-' :o)
2019-11-29 10:14:27 +0000 UTCI'm fairly certain that the voltmeter is a dual slope integrator type. I designed and built one myself while a college student in the early 70's using TTL chips. The cool thing about the technique is that it can be done with digital and analog "jelly bean" components and doesn't require a specialized A to D chip.
HarveyB
2019-11-29 08:51:14 +0000 UTCThe big 3.58 MHz crystal was very common at the time, and hence very cheap. Millions of them were made for use for the phase reference oscillators in Color TV's and because of their cost became the clock for a wide variety of devices.
HarveyB
2019-11-29 08:33:56 +0000 UTCThe "Golden Era of Cool Things"! Most definitely, Fran. Love this - upping my Patreon sub. Thanks, you are one of those Cool Things!
Paul Pruss
2019-11-29 07:24:16 +0000 UTCIt's Metric - both of them are. ;-)
Keith Wright
2019-11-29 06:15:41 +0000 UTC
