How to Make a Portable Handy Lie Detector in Altoid Tin

Hi. I'm paewookyung, and this is my first posting in this site. please take note that
english is not my mother tongue. so please understand some of my gramatic mistake.;

Anyway, let's get this started!
This is a portable lie-detector built in Altiod tin. maybe you could have some fun useing this thing.

note: this detector is less sensitive then a real one. this could be miss some (many) of the lies.

Step 1: Things You'll Need.

You will need some things below for this project.

1. circuit board
2. 10K& resister
3. 47K& resister
4. 470& resister
5. 1M& resister x2
6. 47K& VR
7. knob for VR
8. 2N3904 transistor x3
9. 0.1 ? mylar cap
10. slide switch.
11. 9V bettery snap
12. LED (one red, one green)
13. solding tools.
14. drill
15. basic tools,
16. valcro
17. aluminum foil
....and most of all, Altoid tin!

Step 2: Make a Finger Pads

make a finger pads by sticking a aluminum foil to the valcro.
And don' forget to stick a wire between the valcro and thw foil!

Step 3: Solding the Circuit

Solder the circuit as a diagram below. And before solding the circuit, cut the circuit board to

suitable size to fit in the Altoid tin

Step 4: Drilling the Altoid Tin

Drill the Altoid tin for a VR.

and DO NOT use a sharp-end drill bit. it will tear the tin into half.

Step 5: Put the Floor Sheet

Put the floor sheet in a floor of the tin to avoid circuit from 'shorting'.

and secure is with a glue.

in my case, I used a piece of box, and secure with a hotmelt.

Step 6: Put Everything in Order.

Put everything in a Altoid tin and secure all of them with a glue, hotmelt, E.T.C

Step 7: Done.

Now your lie detector is ready to go. first, put the finger pad to the finger of the 'suspect'
then, slowly, turn the VR until the 'true' LED is light, and the 'false' LED is dark.
then, ask a question to the suspect , when the false LED get light, the suspect is lying.

Step 8: Enjoy!

Just Enjoy that detector. but take this in your mind, this may not be detect lie so perfectly.



And sorry about mistake the 'welcome' to 'walcome' is the photos.


So...have fun.....

Comments

[Peter Parker 123]

when i made this the red led did not light up why?

[Matthew Yang]

It did not light up because the suspect is telling the truth.

[donnachain]

Thank you.

[unikitty7979]

WHERE IN THE WORLD DO U GET THESE MATERIALS!!!!!

[firexwirexx]

you need to look up the materials on amazon you can find them there

[vishnu 1962001]

How can it detect lie

[ciantodd28]

It monitors your heart rate so it can tell if you lie or not

[irontrooper0777]

If you're like most people, lying makes your heart race. It makes you pant. It drives up your blood pressure and makes you drip sweat. A polygraphmachine detects lies by looking for signs of these physiological changes.

[Dylan3D]

resistance in the skin

[robert0joe]

Can I use AA batteries instead of 9V? Like 2 AAs?

[brian251]

no.. prob not enough to trigger the gate and turn on the transistor. you would need about double the base rq voltage to turn it on fullyu, because of the voltage divider at the front of the circuit.

[LiLGq]

well obviuosly its not bearable because 9v batt has 9 volts while 2AA battz has only 3 volts...

[static]

Here the voltage needs to be high enough to insure there is a small current flow over the skin of the suspect. Probably best to stay with 9V, unless you are willing to work with different resistor values to find if this would function at a lower voltage.

[hintss]

6 in series, I think

[mederick]

no..............but you can get some at pep boys in packs of 20!!!!!!!!!!!!

[watermelonpicker]

What wattage is needed for the 47K potentiometer? And what is this red light problem that people keep commenting about?

[brian251]

not much. i didnt build it yet but if you are asking because of the physical size,,, it appears that was selected so you can adjust it by hand outside the case.

the power it needs to handle is very low if you look at the circut.

i have no idea if this thing works, at quick glance looks like it depends on the finger pad resistance changing so that it triggers the LED on... the trimmer allows you to adjuyst the threshold

[MalakA12]

What measurement of the circuit board

[HookEmNoah]

Where did you get the circuit board?

[2919372]

Where did you get materials?!?!?