We found this circuit in a 1963 Radio Electronics. It can be used for remote control. The frequency depends on the coil and the power is supplied by a single battery.
A VCO or voltage-controlled oscillator, which uses only two of the LM3900 amplifiers, is shown in the...
This simple inverter, which we found in a 1987 publication, uses a homemade transformer made based...
This small circuit for the medium or short-wave range, depending on the coil, was found in a...