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.
We found this circuit in an old documentation, using an operational of the time. The circuit...
This circuit is from a 1967 publication and applies to incandescent lamps up to 600 W. Triacs must be...
The TL431 integrated circuit consists of a programmable shunt regulator with an internal...