We find this encoding circuit in an American 1980s amateur radio documentation. The circuit can be implemented with equivalent modern components.
This circuit is as shown in a 1976 technical documentation. It can currently be assembled with any...
Equivalent transistors, like the BC548 and BC558 pair can be used in this circuit that we find in an...
This circuit, from the On Semiconductor thyristor manual, is suitable for incandescent lamps or...