Motion sensor (CB8762E)

This sensitive motion sensor with inductive sensor was found in a 90s Elektor. The circuit uses only transistors to activate a buzzer.

| Clique na imagem para ampliar |

Metal Detector (CB18341E)
This interesting circuit was found in a 1967 Japanese documentation. Transistors are types of...
Simple anemometer (CB23571E)
This assembly circuit using a small motor as a generator was found in Radio Electroics magazine from...
Solar Battery Test (CB1355E )
This circuit is of great use today, when solar energy is becoming increasingly important. The...