Here are the details of the specific parts you will need
Part Total Qty. Description Substitutions
- R1 1 33K 1/4W Resistor
R2 1 5K Pot
R3 1 1.5K 1/4W Resistor
C1 1 1uF 16V Electrolytic Capacitor
Q1 1 2N3565 NPN Transistor
M1 1 0-1 mA Analog Meter
MISC 1 Case, Wire, Electrodes (See Nots)
Notes
1. The electrodes can be alligator clips (although they can be painful), electrode pads (like the type they use in the hospital), or just wires and tape.
2. To use the circuit, attach the electrodes to the back of the subjects hand, about 1 inch apart. Then, adjust the meter for a reading of 0. Ask the questions. You know the subject is lying when the meter changes.
http://www.aaroncake.net/circuits/lie.htm
Simple Lie Detector
- 19th July 2002 08:11 PM #1ElectroMaster
AdministratorSimple Lie Detector
Here's a simple lie detector that can be built in a few minutes, but can be incredibly useful when you want to know if someone is really telling you the truth. It is not as sophisticated as the ones the professionals use, but it works. It works by measuring skin resistance, which goes down when you lie.
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- 9th December 2004 12:34 PM #2Tom McCurdy
Details of Parts
0
- 21st December 2004 03:31 AM #3haerifar
nice post thanks
0
- 4th January 2005 09:14 PM #4Shion Uzuki
LOL cool
0
- 12th March 2005 04:08 AM #5Projek_01
Nice. Thanks for the great ideal
0
- 12th March 2005 04:13 AM #6Projek_01
Hi, I live in a small city and I cant seem to find the correct transistor, do you think there could be any subsitutions? Thanks
Do you think any of these would work?
2N1711
2N3417
2N3439
2N3440
2N3440
2N3771
2N4124
2N4126
2N4400
2N4401
Thanks again0
- 1st June 2005 11:48 PM #7ibook
the meter, does anyone know where to get one of the cheap. I went to local electronics store and the cheapest I saw was 5 bucks. What meter did you use OP. or could you cut me a link to some cheap ones.
0
- 15th June 2005 04:32 AM #8theinfamousbob
I would use the meter out of one of those cheap battery testers that are about $4 US i think...
0
- 18th June 2005 06:23 AM #9yogpra
hi it was gr8
but ..is there any chance that our skin resistance does not go down when we lie..if so the lie detector would say a lie...
thanks
bye0
- 18th June 2005 07:18 AM #10Roboticinfo
reply
Yep
your skin resistance can go down because you are nervous or scared.
So it is hard to tell0
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