Found in an old American documentation this FM modulator makes use of a varactor diode. The circuit can be easily implemented given the small number of components used.
Based on the operational amplifier 741 this circuit can be found elsewhere on this site. This...
We found this circuit in an integrated circuit cookbook from 1974. The circuit can provide larger...
This circuit was found in a 1973 Radio Elettronica magazine from Italy. The circuit can be...