This powerful siren is suitable for warning or alarm systems. The components are current and the transistor 3055 must be mounted on a good heat sink.
This circuit was found in an American documentation from the 60's. The transistors are from the...
This oscillator is indicated for the adjustment of FI of FM radios, having its frequency...
This configuration triggers an external circuit or simply an LED for time given by R1 and C1 (T =...