Door buzzer or alarm (CB20492E)

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

Instrumentation Amplifier (CB4928E)
This circuit makes use of older operational amplifiers, but can be designed on the basis of modern...
Photodiode Amplifier (CB14483E)
Equivalent operational amplifiers can be used in this circuit of the 1990 Linear Databook,...
Class D Amplifier (CB14057E)
This switched, switched or PWM amplifier was obtained in the 1972 RCA linear integrated circuit...