With this circuit it is possible to tune an AM signal using a 5k potentiometer (4k7). The circuit was found in a publication from the 1980s and the PLL can be replaced by an equivalent one, with tests.
This circuit can be installed inside a toy space gun to produce a “Phaser” effect. The circuit is from...
This circuit was found in a 1988 publication. The circuit is an alarm with interrupt sensors that...
The frequency in this circuit is adjusted by P1 and given by C1. Short pulses, as the ones...