This circuit is from a 1968 publication. Here we have several types of resistive sensors with individual adjustments triggering a single SCR. Power depends on the type of sound device to be triggered.
Mouser Electronics already has in stock the new RF transceivers Atmel / Microchip ATA8820 SIGFOX ™ for...
This circuit can be used as a low Power audio booster for experimental projects such as radios,...
With a mains-rated transformer and 1:1 winding this benchtop circuit was found in the January 1995...