This circuit for the 1750 m band was published in the September 1989 Radio Electronics magazine. The range depends on the antenna system and receiver used.
This oscillator has its frequency controlled by crystal and its frequency can be between 100 kHz...
This small crystal microphone transmitter was indicated in an 80s spy book. The range depends on...
The circuit shown is from the 1994 Linear Applications Handbook by National Semiconductor. The...