Alternating Tone Siren 555 (CB25340E)

We found this alarm circuit in a Radio Electronics magazine from July 1990. The power transistor must be equipped with a heat sink.

| Clique na imagem para ampliar |

Ramp Generator (CB1434E )
This circuit was obtained in a 1973s documentation. The transistors may be BC558 for the PNP and...
Differential temperature alarm (CB26159E)
The sensors in this circuit that triggers when the temperature goes out of a certain range are...
MC34071 Active Band Pass Filter (CB15282E)
Other operational amplifiers series, such as MC34072, MC34074, MC35071, MC35072, MC35074 d MC33071...