Found in a 73 magazine from the 1980s, this circuit generates signals from 3.2 to 22 MHz. FETs can be general-0purpose current types. No information about the coils is given.
Pressing and releasing S, the capacitor C1 charges and discharge slowly through the oscillator...
Found in a 1968 US publication, this circuit is designed to measure very weak signals. The...
This receiver receives signals from the VHF band with earpiece or application in a power stage. The...