Found in a RE Experimenter Handbook from the 90s, this circuit is intended for the use of LEDs in a flashing system for Christmas trees. The circuit can be expanded
This 1968 Mullard circuit detects fire by smoke using LDR-type sensors. The circuit makes use of...
Found in the American 73 magazine for radio amateurs, this circuit can test common quartz...
With this circuit it is possible to tune the signals in the 50 MHz band in a common AM receiver around...