This is the circuit of a modified Heathkit kit. The circuit was found in a Radio Electronics from December 1965. The author of the circuit included improvements to the original circuit.
We adapt this circuit of Radio Electronics - March 1990. The magazine no more exists, but the...
This circuit is a digitally controlled variable capacitor. We found it in American documentation from...
In the circuit shown in the figure, when the input voltage rises to 27 V, the TL431 triggers the...