Techmoan video, tape cleaning machine. Seems to have a lot of 74xx chips.

[Ed.Kloonk]

@2:50

Seems to be more chips than needed for the functions it has. What do you think?

[filssavi]

My guess is that the auto rewind functions pre and post cleaning are implemented in digital logic (either FSM or specific timing logic). Probably that implementation is a lot cheaper (and more reliable) than an electromechanical one (no rubber belts to rot, felt to dry up and crumple away, plastic gears to strip, etc)

[newbrain]

My guess is that the auto rewind functions pre and post cleaning are implemented in digital logic (either FSM or specific timing logic). Probably that implementation is a lot cheaper (and more reliable) than an electromechanical one (no rubber belts to rot, felt to dry up and crumple away, plastic gears to strip, etc)

I second the idea of a small FSM: we see 7400, 74107and 74123, going from memory, they are NAND gates, flip-flops (JK?) and a monostable.
So, more or less what you need to have some states and temporization.

[eti]

Seems logical.