Found in a 90s Popular Electronics, this circuit checks if a remote-control transmitter is emitting signals. The sensor is a general-purpose type found in many electronic devices.
Found in a 73 magazine for radio amateurs of the 1980s, this circuit uses a dual-gate MOSFET. This...
This is a bridge for the measurement of low value resistances and high values too. The circuit...
This complementary or bilateral emitter follower was found in American documentation from the 90s....