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.
May 2017 - Mouser Electronics already has for sale the new Littelfuse SP2555NUTG diode arrays for...
This circuit of a 1991 PE Hobbyst Handbook allows the brightness of the incandescent lamp to be...
This circuit was obtained in a 1980 publication, but it can be easily assembled today, as all...