Door buzzer or alarm (CB20492E)

This solar powered circuit was found in a 1991 documentation. The transistor is a general purpose NPN.

Preamplifier with tone control (CB9517E)
Found in National Semionductor documentation this circuit combines a tone control with an...
Series Lamp (CB17626E)
This is the traditional configuration of a standard lamp with a rectifier. Only incandescent lamp...
Power Stage for Alarms (CB12353E)
This circuit can be connected to the output of alarms or sirens with the 555, CMOS or TTL,...