This circuit for VCR recording heads was found in the February 1990 issue of Radio Electronics magazine. The circuit is use do observe signal in an oscilloscope.
This crystal-controlled oscillator was obtained from an American 1980s documentation. The circuit...
The battery charger suggested in the figure has its current limited by resistor R1. This component may...
In this circuit, from a 1977 FET documentation, the FET can be BF245 or MPF102. The circuit...