This shield with full-wave triggering was found in the Radio Electronics Experimenter magazine of 1989. The Triac must be according to the load that must be controlled.
We found this circuit with a Q factor of 25 in the Linear Applications Handbook by National...
Found in a 1967 Electronics World, this preamplifier uses an integrated circuit from that time,...
This circuit uses a special 1950's RCA strobe tube. It can be built with equivalent components for the rest...