Low battery indicator 555 (CB9551E)

This circuit can operate with different voltages, depending on the zener used. We found it in a 90s American documentation.

Overload protection (CB24883E)
This circuit is a continuation of the previous one, serving as a protector against overloads in...
One Transistor High Power Switch (CB990E)
This circuit can handle 25 A unde a 32 V voltage using a hight power old transistor. This...
500 mW amplifier using the 741 (CB6991E)
This circuit was found in 80's Popular Electronics. Transistors are commonly used. The...