This transmitter for the 3.5 and 7 MHz ham radio was found in a 1950s Japan publication. No information was given on the coils and the power supply.
This circuit was obtained from a 2005 Linear Technology application manual. The circuit is...
Small time intervals up o some minutes can be achieved with this circuit. Only incandescent lamps...
This circuit is from a 1977 Radio Shack documentation. It produces a modulated sound of good...