This circuit was found in General Electric documentation from 1964. It makes use of a PUT, called the PNPN planar key at the time. The circuit has two supply voltages.
This indicator circuit used and game machines (arcades) to indicate that the machine is being...
An inproved version of the circuit CIR129E is shown here. The resistorR1 must be at least 5 times...
This circuit is from an old American publication. The indicated transistor is oversized as the 15 V...