Using a varactor or varicap, this 1969 Electronics World circuit has a modulation range from 75 kHz to 52 MHz. Modern equivalent components can be used.
This source can supply currents up to 1 A. The circuit is from Motorola's 1993 Linear Interface ICs....
The purpose of this receiver is to monitor the signal from a nearby transmitter. It was published in an...
In the figure we have a symmetrical power supply stabilized by a zener diode. Transformer and...