Found in old documentation, this circuit can use modern equivalent components. The signal has good strength thanks to the use of a power transistor. The Q1 transistor is a unijunction of the time.
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...