Motorcycle headlight monitor (CB9117E)

This simple circuit was found in Popular Electronics from the 1980s. The circuit uses an LED as an indicator.

LED Binary Counter (CB4345E)
This circuit came out in an American magazine that no longer exists. It's the Electronic...
Code Switch (CB10287E)
This circuit originally came out in a Budget Electronics from 1981. The American magazine no...
LM382 Preamplifier (CB15083E)
This is the traditional audio preamp configuration with the National Semiconductor LM382. The...