This circuit is intended for detecting 3 levels power grid voltage, and it can be adapted to operate with the most diverse voltages. The circuit uses neon indicator lamps.
With a coil formed by 7 turns of 26 AWG wire this circuit operates in the 27 MHz range. But you...
The circuit shown is a commercial electronic voltmeter sold in Japan in the 1960s. The circuit is fully...
This amplifier for recording heads was found in a Radio Electronics from September 1963. The...