We find this encoding circuit in an American 1980s amateur radio documentation. The circuit can be implemented with equivalent modern components.
I got this circuit from an English magazine from 1977. It can still be easily assembled, as the...
The transistors of this circuit can be BC548 for NPN and BD136 for PNP with load up to 500 mA. The...
This 3-transistor amplifier stage was found in documentation from 1963. The transistors are made...