How do vending machines detect 1 doller from 5 doller?

[Passions]

Is it with a laser that scans the bills?

 

[Killbat]

They might have a CCD in there. To detect the value and/or detect frauds.

 

[dennilfloss]

$1 are metallic copper alloy coins whereas $5 are paper bills.

Redefine (Incubus)

 

[xero]

actually......$5 bills have a little strip inside them that tells the sensor (whatever that may be) that it's a five....and $1 bills dont have the strips.

 

[403Forbidden]

$1 = lifetime supply of coke and 25 cents too

 

[kranky]

Dennilfloss appears to be speaking on behalf of the Great White North.
The Loonie.

 

[Imaginer]

Then what about the CHANGE machines in video arcades and also at Gameworks? They can accept $1, $5, $10, and $20s.

 

[Windogg]

Each bill has a different magnetic signature. Bill sorters also work the same way.

Windogg

 

[Imaginer]

So a counterfeit bill would not work right?

 

[drboogie]

What about the older bills without the stripe? The machines still detect the difference between a 20 or a 10 or a 5 even if the bill is an older series.

 

[piku]

You know that if your REAL careful you can take the strip out of 5 dollar bills then tape it to a $1 bill, then use it in a machine then just use the 5 at a register.



You didnt get that from me

 

[dc]

piku, i tried that when i was 13, no go. heh

dc

 

[PCAddict]

What sucks is the new design bills don't seem to work in most of the vending/change machines out there. I've had trouble with those new 5-dollar bills.

 

[vi edit]

midgets

 

[Mday]

it's not CCD.

US currency uses metallic ink (composition classified, and hell if i know) and machines use sensors to detect the patterns. this is why the new bills do not work with older\non-upgradable\non-upgraded machines. the sensors probably do spot checking much like fingerprint recognition is done by computers. (no the entire thing is not scanned and recorded as this is BEYOND current speeds to do properly). the spot checking is probably inherent in the design of the currencies themselves.

the polyester strip tells the machines nothing. the water mark is actually an area where the "paper" is not as thick and tells the computer nothing.

US currency is not smart money, that is, they have no real computer components in them (yet).

I learned this stuffs from NOVA, on PBS. i saw the episodes several years ago.

 

[Mday]

oh, the paper is actually cotton.

 

[Mday]

oh, machines may have gotten more sophisticated since the those episodes aired.

BTW, the bills are actually tested several times and in several places in that pass.

 

[Descend492]

Dennilfloss - I have super-respect (that's above normal respect, for all you lingo-impaired kiddies out there) for anybody who listens to Incubus. Especially from SCIENCE.

 

[xero]

incubus is pimp as hell!

 

[ratkil]

When you have problems with the new bills in changes machines, just wrinkle the hell out of it. They usually work then.

 

[oldandquitemad]

Vi_Edit LOL LOL LOL!

 

[Shazam]

Here's a good article on this subject:

http://more.abcnews.go.com/sections/tech/Geek/geek000601.html