Manual Clock 7400 (CB22411E)

This circuit to produce clock pulses is manually driven. The circuit is TTL and must be powered by 5 V.

2-Transistor MW Radio (CB18309E)
This commercial circuit is from a Japanese magazine from 1967. It uses germanium transistors, and...
Blown Fuse Alarm (CB6109E)
We found this circuit in a 1967 Electronic design. However, it can be easily implemented even...
Null indicator (CB22313E)
This circuit for measuring bridges was found in American documentation from the 60's. Transistors are...