This circuit was obtained from an American 1980s documentation. The frequency depends on the crystal and the circuit may be a PNP that reaches the generated frequency.
Found in Popular Electronics from the 90s, this circuit is intended for a radar emitting pistol. The...
This circuit can generate signals up to 5 MHz according the power supply voltage. Frequency is...
This transmitter emits a modulated signal at a frequency given by the first transistor in the...