Found in American documentation from the 1980s, this circuit has a diode feedback. At the exit we have an indicator LED. The LM3900 is a transconductance operational amplifier.
This small MW transmitter emits its signals at a distance of a few tens of meters, depending on the...
Found in a 90s 303 Circuits, this circuit has an output power of 100 mW. L1 consists of 890 turns...
The coil and sockets of this circuit found in a QST depend on the frequency band that is intended...