This circuit was found in a Ferranti documentation from 1969. The transistors are common types of the company at the time. Smaller equivalents may be used. The output power is of the order of 150 mW.
This circuit can be tuned in a 100 kHz band around the frequency of the crystal. The transistor can be...
The figure shows how to obtain a digitally programmed resistance using the 4066. The circuit is...
This audio oscillator has its frequency determined by C1, C2 and the inductor. The inductor can be...