This CW circuit was found in a Radio Amateur Today from the 890s. The CMOS circuit must be powered by an isolated source and has different dash and dot timings.
The Buck-type DC-DC converter (voltage lowerer) shown in figure 11 is suggested by Analog Devices...
This circuit can be used to directly control direct current loads or higher alternating current loads...
This circuit can turn-on (only) a load (relay or lamp) when S1 is pressed. The circuit can be used as...