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.
This circuit was found in a 1965 General Electric documentation. SCRs and unijunction may be...
The BA1404 integrated circuit (not very easy to obtain) consists of a complete stereo FM...
This circuit is from a Radio Electronics documentation from July 1959. In this documentation the...