Using operational amplifiers of the time, we found this circuit in documentation from the 90s. The configuration can be adapted to use modern operational amplifiers.
This circuit has both frequency and duty cycle control. We found it in the October 1992 Radio...
This power supply is indicated for the supply of not very powerful car radios of the AM and FM...
In the absence of a modulation signal, the carrier of this simple short-range transmitter is cut...