Found in American documentation from the 1980s, this circuit uses common components. The operating frequency range depends on the plug-in coils.
With a touch of S1 this circuit keeps a small strand of nichrome warm enough to light a cigarette....
This Hartley telegraphy oscillator operates with the transmitter signal generating a tone in a...
This circuit turns on a lamp in the dusk and turn off in the down. Only incandescent lamps can be...