Crystal oscillator (CB9504E)

This circuit was found in a 90s Popular Electronics. It can generate signals from 3 to 10 MHz.

JFET Solar Transmitter (CB19441E)
This' 90s circuit emits a signal in the FM band with a few tens of meters in range. The coil is...
Darlington Push Pull Stage (CB6971E)
This circuit was suggested by Popular Elecronics from the 90's. The circuit has high input...
Conventional Astable (CB25650E)
This circuit using 2N2904 general purpose transistors is from a December 1993 Electronics Now...