This simple neon lamp oscillator produces a 140 Hz, 40 V peak-to-peak signal. The frequency is given by the capacitor that can have its value changed. Note the high supply voltage.
The operational amplifier used in this application is uncommon today. This Raytheon circuit can be...
This conventional bistable power control circuit using triac was found in the June 1970 Radio...
This short-range experimental transmitter emits a signal with many harmonics, without modulation. It can...