The two circuits shown show how to obtain an SSB / CW control for receiving this signal top at a common receiver. The circuits were found in an old American manual from the 80's.
Instead of LED bulbs, LEDs with a series 470 ohm 1k resistor can be used in this 80's circuit....
In the figure we have the way to implement a 3-Input logic function OR inputs using common diodes....
This circuit is from Radio Electronics from July 1983. The operational amplifier is of the...