Low Voltage Test (CB22158E)

This is a simple voltage tester for voltages from about 2V to about 15V with the indicated resistor and red LEDs.

8W Transistor Amplifier (CB1318E)
This circuit with complementary output transistors was found in a 1980s publication. Modern...
Emergency Light (CB17503E)
This circuit activates an incandescent lamp (or LEDs) when the light stops hitting the sensor, which...
1 kW power meter (CB5448E)
This circuit is found in an American documentation from the 80's. The circuit measures the power of...