This circuit oscillates in the fifth harmonic of the crystal frequency. The circuit is from a 90's documentation. L1 must be according to the desired frequency.
This circuit was obtained in a 90’s Popular Electronics. The frequency depends on C1, a component...
This short-range circuit can act as a wireless microphone. We got the schematic and the printed...
This sophisticated function generator circuit appeared in the September 1972 issue of Radio...