2 simple electricity detector using BJT transistor

This a very simple detector of electricity in our surroundings. The detector will demonstrate on how sensitive is the three transistor connected the same way as the diagram below. The LED will light when electricity is detected.
very simple electricity detector
With this transistor configuration, the current amplification through the LED is the product of the gains of the three transistors. Example if each transistor has a gain of 150, the total current amplification is around 150 X 150 X 150 or 3.375 million times. You can use this circuit to detect static electricity, current carrying wires, human body or any thing that has electricity.
Part list:
Q1,Q2,Q3 - 2N2222, BC547, 9013 or similar NPN transistor
LED - red , yellow or orange
R1 - 270 ohms 1/4W
R2 - 2 kilo-ohms 1/4W
plate - piece of metal or just ordinary wire conductor

2 comments: