I've posted about this board elsewhere, but it's kind of an interesting old board so I thought I'd post here too.
It was used with the CC-30 Communications Station, introduced in the late 1960's. The PCB is dated 4-69.
The switches are spring loaded lever ("mouse trap") type activated by plungers on the ends of the key stems.
Switches in action:
The key matrix is unusual with all of the keys are on one row with each key on it's own column which passes though an unusual diode matrix before connecting to the ICs.
Since the matrix was one row with 65 columns and I wanted to use my Teensy++, I carefully separated the one row into four (AB, CD, EF, G) and then wired up the rows and columns:
The front plate was rather rusty so I refinished it and cleaned up the case:
I've been using it for a week now (typed this on it) and actually rather like it!
Short video of typing on board:
