Oscillator HA7210 (CB22402E)

This circuit is from an old documentation and can be used to generate signals in different frequency bands.

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...