audioguru

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

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Uncle $crooge

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.

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What's so bad about Microsoft?

Get Opera it's simply a superb browser.

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.

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Uncle $crooge

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.

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MechTronics

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!!

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Don't make me reach through this monitor to slap you a good one!

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

^^^^^ ^^^^^^

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Don't make me reach through this monitor to slap you a good one!

kingkoi

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
http://www.thesourcecc.com/estore/pr...ine&tab=3#more

• Transistor
http://www.thesourcecc.com/estore/Product.aspx?language=en-CA&catalog=Online&category=Semi+Conductors%2fIC's& product=2761617

• Capacitor
http://www.thesourcecc.com/estore/Pr...roduct=2720802

• Resistors
http://www.thesourcecc.com/estore/Pr...roduct=2719018

Pot
http://www.thesourcecc.com/estore/Pr...roduct=2711720


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.

audioguru

You need a cheap 1mA analog meter movement, not an over-priced old multi-meter. I don't know if anybody sells a meter movement anymore.

You need a linear 5k potentiometer, not an audio one.

The circuit detects that a person is sweating, not lying. Some people lie all the time and do not sweat. Some people sweat when they are telling the truth.

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Uncle $crooge

wmmullaney

Aw, c'mon audio, why do you think? I'ts so cool, this is a great starter poject.

(Are all Canadians like that?)

audioguru

The lie detector circuit doesn't detect lieing. It is just an ohm-meter that detects sweating and the amount of pressure on its probes.
If you want to know if somebody is sweating then just look at them, you don't need an stupid simple ohm-meter.

If you want to know if someone is lieing then look on Google at all the things that are needed for experts to guess (frequently wrong) if they are lieing.

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Uncle $crooge

Roff

It is a good idea to warn people that this is really not a lie detector, but it's still a magical little electronic thing that you can build yourself, play with, show your friends, and marvel at what you hath wrought.
Hell, I started out with things as simple as putting a couple of small turns in a piece of copper wire, putting it across a flashlight battery, and wondering why the little coil was the place that glowed red.

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Ron

kozer

hi to everyone!!!this is my first post!!!in my school they tell us to make a simple circuit with orcad and i find lie detector a good simple project but i cant find in libraries where M1 and electrodes are...Can you help me by telling me the names of the parts plz...??????