Found in a 90s Popular Electronics, this circuit triggers a load from the audio signal applied to its input. The controlled load depends on the MOSFET.
Found in an American 1980s documentation, this circuit generates frequencies in the range...
This circuit, obtained from the component manual used, has an ultra narrow 1 kHz range given by...
Molex is using the FFC / FPC Premo-Flex jumpers for inter-board and inter-plate interconnects...