Electric Field Detector

Hi guys..!! Today i am posting an other circuit that is an "Electric Field Detector". 
It is a wonderful project and i designed it 7 years before for my school project. And it worked very well. I still have that and it is working well. I was about to fill the target of 500 circuits based on 2N3904 and i was awarded by my teachers for this circuit and an InfraRed interruption Switch of Burglar alarm circuit.

Well here is its basic circuit. It is based on three transistors and three resistors, one led and a battery.
Later i'll be posting its modified circuit diagram. I did its modification and made it about 30 millions gain. And that modification will detect electric field and tell you about how much electric field is detected. So visit this blog regularly..!!

 

You can click on this circuit to enlarge this schematic.

Components:

• 3 - Transistors  = 2N3904      [Alternative = KT312, BC547, 2N2222]
  
• 1 - Resistor      = 100k Ohm   [0.25Watt] 
• 1 - Resistor      = 1M   Ohm    [0.25Watt]
• 1 - Resistor      =  220  Ohm   [0.25Watt]
• 1 - Small Piezo-buzzer and LED
• 1 - Toogle Switch (Or Any Type of switch)
• Probe                   ( Or Twist any hard copper wire to make a probe. It will work too.)

Beside these components a 9v Battery or a DC power supply is also required. Or you can use 3 small button battery of 3v in series that will make 9v too.