This circuit is from Radio Electronics from March 1985. The circuit uses common components at the time and LEDs as indicators. The power supply is 9V.
The TAA865 integrated circuit used in this 1986 project is no longer common today. The circuit is a...
) These two circuits were obtained in a 1977 Radio Handbook. The transistors are from that time,...
The circuit shown is from the Motorola Linear Databook of 1990. It is based on the Motorola T...