Recreation first analog to digital with 1942 Thyratron tubes

[Jonpaul]

Bonjour, just got a new set of matched 1953 vintage RCA 2050 Thyratron Argon tetrode tubes.

Installed into the SIGSALY Quantizer ADC recreation, now calibrated perfect 6db/step CAL.

From my IEEE Spectrum Feb 2019 article.

Your thoughts appreciated.

Jon

 

[bondini]

From my IEEE Spectrum Feb 2019 article.

Hi Jonpaul,

What was the title of your Spectrum article?

 

[MarcelvdG]

Interesting. I knew Bell Labs used cathode ray analogue-to-digital converters in the late 1940's and early 1950's, but I didn't know about thyratron ADCs.

Edit: I had read about the American digital voice encryption in WWII, I just didn't know it was called SIGSALY, nor that it used thyratron ADCs. I always assumed it used an earlier version of the later cathode ray ADCs. (Turing later designed a much simpler voice encryption machine based on analogue modulo addition (Delilah), but that couldn't handle fading.)

https://en.m.wikipedia.org/wiki/SIGSALY

 

[OldHector]

Thanks, that was an interesting read!