This circuit was found in a 70s documentation. The transistor is from that time. L1 has 4 turns of wire 20 in the form of 3/32 inches and L1 has 10 turns of the same wire,
This circuit was found in General Electric documentation from 1964. It makes use of a PUT, called the...
This mid-frequency amplifier circuit was found in an American publication from the 1950's. The...
The circuit with a common operational amplifier uses a zener as a reference. The circuit is from...