Simple Lie Detector

[ahya]

question

hi! how accurate is this project? i just want to know because we will defend this project and can you give me some documentation about this projects... it so cool.. thx anyway...

 

[audioguru]

A digital ammeter might need a battery to power it that is separate from the battery in this circuit.

 

[ahya]

hi! i just need to know how accurate this project is and can someone give me documentation about this project, i really need it badly...

 

[Nigel Goodwin]

hi! i just need to know how accurate this project is and can someone give me documentation about this project, i really need it badly...

It's not at all accurate, lie detection is a very complicated subject, and not terribly accurate anyway!.

 

[audioguru]

The project shows resistance changes, not lieing.
Some people get nervous and sweat when they lie. Then their skin resistance becomes lower. Other people don't sweat when they lie so then the project is useless.

 

[ahya]

thanks for answering my question but can any1 post a word doc about this project? thanks in advance...

 

[audioguru]

Why post a Word Doc?
It is a simple ohm-meter.

 

[Roff]

Why post a Word Doc?
It is a simple ohm-meter.

A Word doc makes it really easy to turn it into a report for a school assignment. ???

 

[blueroomelectronics]

hi! how accurate is this project? i just want to know because we will defend this project and can you give me some documentation about this projects... it so cool.. thx anyway...

What are you defending it from?

 

[Hero999]

A Word doc makes it really easy to turn it into a report for a school assignment. ???

Too, easy, change the name, print it off and there you go.

 

[audioguru]

Why would little kids want to play with this simple circuit?
Why would anybody want to play with this stupid and simple circuit??

 

[Hero999]

Is it so bad if it gets people into electronics?

I don't mean to sound like that old fart of a moderator on the other forum but please don't discourage people.

I agree that this circuit is crap but we need silly circuits like this to get people started off. I'd rather someone attempt to build something like this for their first project rather than attempting something truely silly like a 3kW inverter or just beyound their level of understanding like a random number generator without a microcontroller when they don't even know you can power a radio that requires 12V@100mA from a mains adaptor that can 500mA, without a series resistor.

 

[audioguru]

My first few electronic projects were kits. An FM tuner, a stereo multiplex adapter for the FM tuner, an audio amplifier and an oscilloscope.

Then I made a Wien Bridge sine-wave/square-wave generator from the project in a magazine. They all worked well.

I made a transistorized voltmeter that didn't work well. Something like this lousy lie detector circuit.

 

[Krumlink]

My first electronics project was a alternating flasher using the 555. That's becuase the 555 was around when I Started Old farts (Im joking, I bow to your superiority).

I then made a inverter oscilliator that then made a dual LED flasher and that was in turn controled by light. I brought it to school and People thought it was a bomb.

Another was A high frequency oscilliator (555 again ). I would turn it up as High as it could go and People would be freaking out because Only a couple could hear it and nobody believed them. AWESOMEST DAY EVER!

I then brought Spaghetti to school, and that wasted all day. It was really fun watching the teachers asking what voltage is, amperage is, wattage and stuff. Most of those teachers were crap, only teaching what they could read out of a book.

 

[HiTech]

My first project was a D cell, a lightbulb and some hook up wire! I took it to the dinner table with me while I ate! From there I got one of those 200 in one kits and then it was off to the big times: Heathkit HW-101 100 watt SSB transceiver!!

 

[AND_ECE]

oh wow what a nice design!!!! for mw cos am a 1st timer of this field
what bout a buglar alarm consisting a transistor

 

[chir]

this ckt is good but i knew this ckt befor itself

 

[HiTech]

this ckt is good but i knew this ckt befor itself

^^^^^ ^^^^^^

 

[kingkoi]

help me sir

I have gathered all materials for this Simple Lie Detector.

Except for 0-1 mA Analog meter, it is not available in our place.

All they have are 20mA Analog meter. But I will still try to find 0-1 mA.

To all of you Sir, i would like to know what would be the appropriate replacement for the 0-1 mA analog meter.

Thank you sir..

 

[Hydrogenboy]

Hey,
I have read that some of you think that this project is stupid, and I know that I can/have done better than this, but I just want to make a Lie thingy, because I never know when someone is lying. So, I think I have found all the parts, but I just want someone to make sure they are the right ones.

• Analog Meter
**broken link removed**

• Transistor
**broken link removed**

• Capacitor
**broken link removed**

• Resistors
**broken link removed**

Pot
**broken link removed**


I believe this is all that I need to buy, I might have the Resistors, if I looked hard enough, but I want to make sure these items will work. Will they? Thanks.