# How to Detect Fake MONEY (USD)

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Easily spot counterfeit money at home with this trick, without any special equipment. Enjoy.
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UPDATE: (infos from different sources)
Many of the early bill changers took advantage of the fact that U.S. bills are printed with magnetic ink. They could therefore use magnetic heads (like the ones in a cassette tape recorder) to pick up signals from the bills. Areas of the bill (like the background behind the president's face) would generate signals at a specific frequency, and the detection of this frequency would validate the bill. Different bills generate different frequencies, so the frequency can also help determine what the denomination is.Many of the early bill changers took advantage of the fact that U.S. bills are printed with magnetic ink. They could therefore use magnetic heads (like the ones in a cassette tape recorder) to pick up signals from the bills. Areas of the bill (like the background behind the president's face) would generate signals at a specific frequency, and the detection of this frequency would validate the bill. Different bills generate different frequencies, so the frequency can also help determine what the denomination is.

# Genuine dollar bills have a certain conductivity, and checking for the resistance of a bill can authenticate it.
# Inks and papers have different fluorescent properties, and these properties can help tell real from counterfeit bills.

It is a special ink that CANNOT be removed. If no ink shows up it means the bill is a counterfeit.
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You can check this video on metacafe or my channel for other "how to" videos.

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## 36 Discussions

there is also another way. hold a bill in the light. a secret image should appear. 5\$- three five on the left and one five on the right 10\$- before- a white circle after- a head shold appear in the circle 20\$- TWENTY USA, USA TWENTY should dissapear, and a head should appear next to the twenty with a green circle thing on it.

You need to go a little farther with your explanation. The watermark(image of a head) in the blank, white area on the right side of the 10, 20, 50 and 100 dollar bills SHOULD MATCH the face printed in center of the bill. We received a \$50 bill that one of my employees didn't catch because they saw a face in the watermark area, BUT it was the wrong face. Someopne had bleached a 20 dollar bill and printed a \$50 bill on it. THE FACES HAVE TO MATCH!

at gap they cannot report shoplifters and the must accept money unless one side is white. You could use a 1 mil bill and they couldn't stop you.