This circuit is designed to measure very weak currents, in the order of picoamperes. We found it in an American documentation from the 80s. The integrated circuit is from that time.
This two-port monostable of the 4001 was suggested by an article in the April 1988 Radio...
We found this circuit in a documentation from the 70s. Semiconductors are from the era and can be...
This circuit is from 1992 documentation. The transistor can be a TIP42 with a good heat sink for...