cvicisso
Newbie level 5
![Newbie level 5](/styles/images/ranks/blevel2.gif)
Bottom Line Up Front: NO ELECTRONICS EXPERIENCE AT ALL! I'm too old/stubborn to learn it at this point, and I have exhausted all other resources. So... please help me b/c you're my only hope! ![Smile :) :)](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
Background info:
- Some pre-1965 U.S. coins contain 90% silver.
- U.S. half-dollars minted between 1965-1970 contain 40% silver.
My goal:
- I would like to be able to determine whether a coin roll (literally, a 'stack' of coins wrapped in paper) contains silver (either 90% or 40%) WITHOUT opening the roll.
My 'vision':
- Silver, as you probably already know, is the most electrically (and interestingly, thermally) conductive metal on earth, so I'm hoping that by passing the coin roll (containing MOSTLY copper-clad coins) through some sort of a simple coil, I can detect the difference in [not sure - fill in the blank?] as the roll is moved sloooooowly through the coil and the conductivity (or whatever) changes as the silver coin passes by the coil. I don't need to accurately 'measure' anything - I don't need numbers - I just need to be able to detect the difference in copper-clad and silver-containing coins. Something like a needle jump or an LED when a certain threshold is passed, for example. The VAST majority of coins will be copper-clad: silver-containing coins will be the very rare exception.
** If I could discriminate between 40% and 90% silver coins (higher needle jump or different color LED for example), that would be super-cool too... but if that's too hard, it's not a necessity.
Am I off base? If not - what shouuld I try to detect/measure? Inductance? How do I [easily] do this?
Thanks in advance for any help you can provide this electronically-illiterate soul!
Background info:
- Some pre-1965 U.S. coins contain 90% silver.
- U.S. half-dollars minted between 1965-1970 contain 40% silver.
My goal:
- I would like to be able to determine whether a coin roll (literally, a 'stack' of coins wrapped in paper) contains silver (either 90% or 40%) WITHOUT opening the roll.
My 'vision':
- Silver, as you probably already know, is the most electrically (and interestingly, thermally) conductive metal on earth, so I'm hoping that by passing the coin roll (containing MOSTLY copper-clad coins) through some sort of a simple coil, I can detect the difference in [not sure - fill in the blank?] as the roll is moved sloooooowly through the coil and the conductivity (or whatever) changes as the silver coin passes by the coil. I don't need to accurately 'measure' anything - I don't need numbers - I just need to be able to detect the difference in copper-clad and silver-containing coins. Something like a needle jump or an LED when a certain threshold is passed, for example. The VAST majority of coins will be copper-clad: silver-containing coins will be the very rare exception.
** If I could discriminate between 40% and 90% silver coins (higher needle jump or different color LED for example), that would be super-cool too... but if that's too hard, it's not a necessity.
Am I off base? If not - what shouuld I try to detect/measure? Inductance? How do I [easily] do this?
Thanks in advance for any help you can provide this electronically-illiterate soul!