On interfaces, paper tape readers/punches,

[Tony Duell]

> I do indeed have a board around here someplace that I have no info on,  b=
> ut=20
> it's got a row of those -- 12? -- and the outputs of them seem to be coup=

I assume 'those' means HE567s

> led=20
> to a couple of 7400 chips.

Had it been 7 or 8, I'd have guessed they were set to the row and column 
tones for a standard teletphone DTMF keypad, and that the logic combined 
them to produce a separate output for each key.

With 12, it _might_ be a selective calling decoder from a private radio 
system, or soemthing like that.

-tony