The circuit presented uses two common transistors and is powered by the circuit being tested. The circuit is for TTL logic, since its supply is 5 V.
Found in documentation from the 70s, this circuit uses an operational one from that time. It goes for...
This circuit is from an old American publication. It divides a 40 to 60 MHz TTL signal by integer...
This 2004 circuit is based on the ionization effect that occurs in old incandescent lamps with...