Found in a 1990s US publication, this alarm circuit detects when a light beam is interrupted. Optical resources may be used for the sensor and instead of the alarm a relay may be used.
This old circuit from a documentation from the 70s disconnects a TV from a signal obtained on the...
This traditional complementary symmetry circuit provides 20 W of rms power at a load of 8 ohms...
Using a CA3130 and a power transistor, this circuit can deliver a current of up to 500 mA with the...