AC voltage control (CB8904E)

This circuit was found in a 90s Hands On Electronics. The semiconductor component is a Triac of the time.

Operational Transistor Control (CB12177E)
With this circuit it is possible to control an operational amplifier so that it switches an input...
40W Transistorized Amplifier (CB11574E)
This circuit consists of a traditional amplifier version with complementary output using BD series...
Microphone Preamp (CB6036E)
This circuit was obtained from a Texas Instruments 1985 document. The circuit is powered by 1.5 V...