This alarm siren circuit has a latch. We found it in an article in the January 1975 Radio Electronics magazine. Note the power given by Rx and the speaker. It can be increased by changing Q1.
Using SCRs, this circuit from a 1967 General Electric manual allows full wave load control with SCRs....
This power supply for TTL and CMOS circuits with a voltage of 5 to 15 V was found in the Special...
This circuit is from a Radio Electronics from February 1970. The circuit has a light bulb as an...