We found this circuit in a William Sheets. The circuit is for frequencies up to about 500 kHz.
This amplifier with the RCA CA3018 integrated circuit was found in the August 1970 issue of Radio...
This circuit generates sinusoidal signals that depend on the input oscillator. The circuit is from...
This fast-acting circuit uses any phototransistor as a sensor. The circuit drives a 30 V relay, but...