Hamboneyard.comSurplus · Vintage · Shack-tested
Linear amplifier keying circuit — photo 1

Description

It's a keying circuit, folks. It's built to work with a negative-ground powered DC relay. The 4.7k 2-Watt resistor supplied with this board is installed between the solder pad marked "In" and the center pin of the amplifier's input or "Radio" socket.

Full description and all photos on eBay

More in Amplifiers