Found in 1967 documentation, this circuit makes use of period transistors and drives a common light bulb. Nothing against it being adapted to use LED.
This General Electric circuit was published in 1970. The LED is infrared and the voltage according...
This small two-transistor amplifier was found in the April 1994 issue of Electronics Now magazine. This...
This circuit operates at a voltage of 1.3 V from a single mercury cell. We found in an old...