Simple lie detector diagram

[sokrat]

Hi all

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.

S 8O KRAT

 

[radix]

Re: lie detector

Just curious. How many people here believe that lie detectors actually work?

Even if you measure blood pressure, pulse, respiration, skin resistance, and let's through in pupil dilation for good measure, what are you actually measuring? You're measuring a physiological "response" to a question. Is that response a lie? That is something the equipment doesn't tell you.

Radix

 

[IC_Digital]

In my country lie detectors are used not only for True/False detection, but also for the reaction of the body after some shock. It?s a part of tests to enter Special Forces

 

[sokrat]

Re: lie detector

Just curious. How many people here believe that lie detectors actually work?

Even if you measure blood pressure, pulse, respiration, skin resistance, and let's through in pupil dilation for good measure, what are you actually measuring? You're measuring a physiological "response" to a question. Is that response a lie? That is something the equipment doesn't tell you.

Radix

Dear radix

before any repply please read the post first :roll:

i say " simple lie detector & It is not as sophisticated as the ones the professionals use "
NOTE :
This forum for Hobby Circuits and Small Projects





Thanks

S 8O KRAT

 

[radix]

Re: lie detector

Dear Sokrat,

Actually I did read your post and I believe I understood it quite well. I wasn't commenting on the sophistication of your design. The part of your post that I found interesting was that the design "can be incredibly useful when you want to know if someone is really telling you the truth". That assumes that even the most sophisticated "lie-detector" available today is capable of detecting a lie.

If you have any understanding of lie-detectors you know that it doesn't actually detect a lie. It detects a bodily (physiological) response to a question. It is up to the polygrapher to try to make a determination of whether or not the response is a lie.

I'm not slamming your post, I was just curious as to how many people that read this post actually believe that lie-detectors work. May I should have started a poll instead? :?

Cheers,
Radix

 

[sokrat]

Re: lie detector

OK :wink: radix


If you have other design or more good infromation 8) send it :idea:


S 8O KRAT

 

[geppoilfolle]

Re: lie detector

I know there is also a software lie-detector, based on the stress of the voice of the lier. I don't remember the name of this program, but i think you have no difficult to find it by g00gl3 or similar, if you want. I remember also that the only need is a good sound card and a good microphone. Could be quite nice to compare the program whit the circuit proposed in this forum, or also to use the two toghether.

Bye all

 

[sokrat]

Re: lie detector

I know there is also a software lie-detector, based on the stress of the voice of the lier. I don't remember the name of this program, but i think you have no difficult to find it by g00gl3 or similar, if you want. I remember also that the only need is a good sound card and a good microphone. Could be quite nice to compare the program whit the circuit proposed in this forum, or also to use the two toghether.

Bye all

Dear geppoilfolle


If you remember link tell me


S 8O KRAT

 

[Audioguru]

lie detector

The "lie detector " toy does not detect lies. It detects how much pressure the probes have on the skin and it detects when a person is sweating. Many people sweat when they tell the truth.