This circuit from General Electric was found in a 1967 documentation. The SCR is of the time, as are the transistors, but equivalents can be used.
This receiver is from European documentation from the 90s. The integrated circuit is uncommon, and the coil...
This is the traditional unregulated power supply configuration with full wave rectification. For currents...
To implement this function, we need a relay with double contacts, as shown in the figure. With a...