This circuit was found in 1980's Radio Electronics. The circuit produces a 1500 Hz modulate 35 kHz. The components used are still common.
This circuit was obtained from an English magazine from 1976. The transformer has a current of 1.5...
We found this circuit in a 1974 documentation. The NPN transistor can be the BD135 and the PNP the...
In this 1964 Electronic Design circuit, the frequency division of the signal is done according to the...