Found in a 90's EDN this circuit can be used as a shield. The transistor is a general-purpose type and the frequency of the emitted sound is determined by R1 / C1.
This light-activated switch triggers a 6 V relay. The circuit can operate with 12 V and relays for...
Mouser Electronics is supplying the SMi (Silicon Microestructures) uncompensated low pressure...
This small two-transistor amplifier was found in the April 1994 issue of Electronics Now magazine. This...