Found in ancient American documentation this circuit uses semiconductors from the thyristor family such as SCRs, Triacs and unijunctions. The circuit can control loads up to 550 W with the indicated triacs.
This circuit triggers a relay when the phone rings. An application is like remote doorbell. The circuit...
This circuit uses a resonant reed switch at the trigger frequency. The circuit is from General...
This circuit was obtained from the Texas Instruments component datasheet which can supply currents of...