This circuit for receivers was found in an American documentation from the 90's. The circuit operates at up to 500 MHz. The integrated circuit used is uncommon nowadays.
This simple circuit shows how you use a TTL to decode logic levels from a BCD output to drive a...
Obtained from a 1969 documentation, this circuit can operate at frequencies up to 500 Hz, counting up...
The circuit of a 1968 publication can be implemented with more modern transistors such as BC548 for...