Simple Lie Detector

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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.

Schematic

Parts

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

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.

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.

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Comments

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Ace Simple Lie Detector-RE: person requesting how to video... Friday, September 04, 2015 4:55:20 PM

To the person asking that a "how to build this" video be sent to him: (prince-something was username)... Dude, if you cant build THIS circuit, (which by the schematic you could almost thumb-twist together) maybe you should consider NOT going anywhere NEAR ELECTRONICS, OR ANYWHERE you could hurt yourself or others... In other words, ask George to tell you about the rabbits..! And dont leave home without wearing your helmet!!

Atif Simple Lie Detector Sunday, February 08, 2015 5:19:29 AM

can we use digital meter in place of analog???

prince coffie Simple Lie Detector Sunday, September 28, 2014 9:52:11 AM

please am finding it difficult to build this circuit and i need your help by sending me a video tutorial of how to build the simple lie detector.hope my request will meet your kindest consederation

md zarif Simple Lie Detector Saturday, March 22, 2014 1:09:44 AM

yes, this is the really very nice project and i made also.. its working bindas....

anonymous Simple Lie Detector Monday, September 09, 2013 12:59:02 AM

Dear Sir or Ma'am, I would like to ask if the pointer of the analog meter goes down when somebody lies or is my analog meter the problem? Also, when it is being tested, does the meter have to move from 0 then so on or from any number as long as it moves then it is lying? please reply asap. i need thisproject two days from now :(

prateek Simple Lie Detector Thursday, November 22, 2012 10:58:06 AM

is this really works if yes plz mail me back coz i wana do this project

sneha Simple Lie Detector Tuesday, November 06, 2012 2:03:46 PM

I want to ask about how does analog meter works in dis lie detector??

ramya Simple Lie Detector Friday, August 24, 2012 7:29:13 AM

ARE THE 4.5V IN THE DIAGRAM BATTERIES ? HOW MUCH WE NEED TO GIVE THE POTENTIAL VOLTAGES

ramya Simple Lie Detector Friday, August 24, 2012 7:26:01 AM

i am a BTECH 3rd year student .i want to submit this project in my college as a minor project so please give me it's complete information project report and pdf file .please send as early as possible we have a limited time.thank u ..................

anonymous Simple Lie Detector Monday, August 06, 2012 4:00:21 AM

AHEM. Professional lie detection examiner specified "ask yes or no questions only" by preparing brackets (sets) of questions ahead of time

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Ace	Simple Lie Detector-RE: person requesting how to video...	Friday, September 04, 2015 4:55:20 PM
To the person asking that a "how to build this" video be sent to him: (prince-something was username)... Dude, if you cant build THIS circuit, (which by the schematic you could almost thumb-twist together) maybe you should consider NOT going anywhere NEAR ELECTRONICS, OR ANYWHERE you could hurt yourself or others... In other words, ask George to tell you about the rabbits..! And dont leave home without wearing your helmet!!
Atif	Simple Lie Detector	Sunday, February 08, 2015 5:19:29 AM
can we use digital meter in place of analog???
prince coffie	Simple Lie Detector	Sunday, September 28, 2014 9:52:11 AM
please am finding it difficult to build this circuit and i need your help by sending me a video tutorial of how to build the simple lie detector.hope my request will meet your kindest consederation
md zarif	Simple Lie Detector	Saturday, March 22, 2014 1:09:44 AM
yes, this is the really very nice project and i made also.. its working bindas....
anonymous	Simple Lie Detector	Monday, September 09, 2013 12:59:02 AM
Dear Sir or Ma'am, I would like to ask if the pointer of the analog meter goes down when somebody lies or is my analog meter the problem? Also, when it is being tested, does the meter have to move from 0 then so on or from any number as long as it moves then it is lying? please reply asap. i need thisproject two days from now :(
prateek	Simple Lie Detector	Thursday, November 22, 2012 10:58:06 AM
is this really works if yes plz mail me back coz i wana do this project
sneha	Simple Lie Detector	Tuesday, November 06, 2012 2:03:46 PM
I want to ask about how does analog meter works in dis lie detector??
ramya	Simple Lie Detector	Friday, August 24, 2012 7:29:13 AM
ARE THE 4.5V IN THE DIAGRAM BATTERIES ? HOW MUCH WE NEED TO GIVE THE POTENTIAL VOLTAGES
ramya	Simple Lie Detector	Friday, August 24, 2012 7:26:01 AM
i am a BTECH 3rd year student .i want to submit this project in my college as a minor project so please give me it's complete information project report and pdf file .please send as early as possible we have a limited time.thank u ..................
anonymous	Simple Lie Detector	Monday, August 06, 2012 4:00:21 AM
AHEM. Professional lie detection examiner specified "ask yes or no questions only" by preparing brackets (sets) of questions ahead of time