This TV remote control receiver uses a ratchet system to activate an old drum-type selector to change channels. A common system at the time. The circuit is from a Radio Electronics from February 1961.
We found this circuit in an old documentation from 1988. The circuit captures the heartbeat...
This circuit was found in a Popular Electronics from the 90s. The transistors are general purpose, and...
This circuit is from a documentation from the 70s. The transistors are types of germanium of the...