This circuit was found in a 1967 General Electric documentation. Tunnel diodes can oscillate at very high frequencies. These are not currently easy to obtain components.
This circuit is from the 1993 Motorola Linear Interface Circuits. The source does not have to be...
This range is normally used in marine communications as indicated in the 1989 documentation. The...
This shield circuit is from a 1968s Motorola documentation. The relay is according to the supply...