Published in a February 1978 Radio Electronics magazine article, this digital circuit uses some of the integrated circuits of the time. The circuit uses a LED bargraph.
The circuit consists of a MAT (Very High Voltage) oscillator that, applied to a protected metal...
A narrow range of frequencies around 1 kHz is rejected by the high Q filter shown in the figure,...
This transmitter circuit for the 27 MHz band uses 4 common FETs and has the details of the coils...