This shield circuit is from an American documentation from 1969. The components can be modified according to the relay and power, and the coupler can be of a modern type.
We found this circuit in Harris' 90s documentation. The circuit applies to modern operational...
Found in a 90s magazine for radio amateurs, this circuit can generate frequencies up to 45 MHz...
This is yet another balanced modulator circuit for SSB transmission. This two-diode circuit was...