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Vacuum tubes in a 1402?? - indeed :-))

Hidden away, in a deep dark place in the 1402 card reader/punch, is a vacuum tube test amplifier (overdriven to be a switch) used to drive the neon tubes on the 2 test alignment rotating disks. One rotating disk for the card reader event timing, and one rotating disk for the card punch event timing.

Evidently the directive, sometimes called "Solid State in '58", did not apply to test/alignment equipment. There is a suspicion that the vacuum tube test amplifier was well hidden to reduce customer/competitor comments and questions ;-))

For further details and usage, see - well, we gotta work that out ;-))
Photo by Ken Shirriff, uncovering the unit by Anonymous