Found in a 1965 Electronic Design the purpose of this circuit is to control the gain of a stage by applying an external voltage. The circuit operates at high voltages.
This circuit with TTL output was found in a 1968 EEE. The transistor can be of general use. The...
This circuit for controlling high power LEDs (up to 2A) is from a General Electric documentation from...
This very simple circuit was found in a 1977 documentation. The L1 coil has 3 turns of AWG wire 22 to...