Found in an old publication, this is a transmitter with a spark coil. The high frequency oscillations of the high voltage spark generate the signal thrown at the antenna.
Found in a 1960 Sylvania manual, this circuit can be implemented with a modern equivalent...
This configuration, already presented in other points of this section and website, is of a...
We found this precise crystal oscillator for the 144 MHz band, depending on the crystal used. The...