If you were using HP devices, they drove each tube individually with a 4-bit flip-flop memory card and a 1 of 10 decoder made from neon lamps on a photosensitive plate. The decoder cards were the brains, memory, and decoder for the unit.
AFAIK, most other manufacturers used custom solutions or scanned with 74141s (I think that's the driver IC) just like LEDs and LCDs are done today. You could do it super fast because neon is instant.
As I recall, there were few HP peripherals on the old bench until I built a rack and stack sequential device tester that supported handlers. None of the old equipment had IEEE488 GPIB interface bus. Much of the new equipment in my rack and stack was HP equipment, all had GPIB.
We used to make the full complement of decoder/drivers at my local Fairchild facility and later at Nat Semi. The internal part name for 74141 was , IIRC.
That's pretty cool. I missed the era where 74 series stuff was designed.
Man, those designs look so simple today! Towards the end of my career I was supporting Cyrix MediaGX and M2 uPs - around the 200mHz-300mHz period of the uP wars. We were faster than AMD for a few months, then in #3 position and losing ground. National Semi had no business being in the uP business - under funded, under staffed, pushing the limits of our fab. You wouldn't believe the stress levels of a uP test engineer during the CPU wars.
FAST(Mxxx devices) devices (Fairchild Advanced Schottky Technology) were the current hot thing when I first started. A couple of years later we introduced FACT (Cxxx) devices (Fairchild Advanced CMOS Technology) along with the first AC/DC test platforms in the house, the MCT2000 based on x86. Then National bought Fairchild and they pared down the duplicate device offerings. In most cases they kept the Fairchild parts and discontinued the equivalent National part. Those MCT2000s were real workhorses. We upgraded the CPUs every couple of years to reduce test time.
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