Solar radio (CB20485E)

This circuit is from a 1991 publication. The integrated circuit used is an integrated radio from that era.

Simple Alarm (CB16496E)
This circuit triggers an oscillator when any of the sensors is opened. The circuit can be powered by...
Electronic Bird (CB18670E)
This circuit imitates the singing of a bird intermittently with the intermittency determined by C1...
Super simple amplifier (CB23699E)
This is a high gain circuit with 3 transistors connected in direct coupling. The circuit is from a...