Description

This app offers a cheap and easy to use method to help detectfakebullion coins, by examining their resonance frequencies.Theresonance frequencies of an object are determined by theobjectsshape and material. If the shape and weight of a silver coiniscorrect, but the material is not actually silver, then aresonancetest could detect this. This is also known as a "ringtest" or"ping test". Unlike the manual "ring test", this app doesnotrequire that the user knows exactly how each coin should sound.Theapp will also detect resonance frequencies above the range ofhumanhearing. This youtube video shows how to use thisapp:http://www.youtube.com/watch?v=5pZnqp3bl3A Currently, thesecoinsare supported: 1oz American Silver Eagle 1oz Silver Buffalo,flatedge 1oz Silver Buffalo, reeded edge (Sunshine mint) 1ozLibertySilver 1oz African Wildlife Elephant 1oz Silver Maple Leaf1ozPhilharmonic 1oz Australian Kookaburra 1oz Australian Koala2ozAustralian Lunar 1oz Chinese Panda Swedish 100krcommemorativeSwedish 5kr 1954-71 Morgan and Peace silver dollars1oz Krugerrand1oz Australian Gold Kangaroo 1oz American Gold Eagle1oz GoldVienna Philharmonic 1oz Gold Lunar 1oz Gold Buffalo 1ozGold MapleLeaf $20 Double Eagle gold coin 20 Franc gold coinBrittishsovereign gold coin There is also a "generic" feature wichsupportsALL .999 1oz silver coins with diameter 36-42mm. Just enterthediameter of your coin, and the app will automaticallycalculatewhat it's resonance frequencies are. How to use this app:1. Forbest results you should perform this test in a reasonablysilentroom. Some electronic devices may produce high-pitch noiseswhichcould interfere with the test. 2. Select the type of bullioncointo test from the drop-down list. 3. Press the microphone buttontostart the test. 4. Blue lines indicate the expectedresonancefrequencies of the selected coin. 5. Balance the coin onyourfinger, near the microphone of your smartphone. Tap the coinusingyour fingernail, or use some hard object. Do NOT use a secondcointo tap the first one, since the sound from the second coinmayaffect the results. The sound level required depends onthesensitivity of the microphone in your Android device. Formostdevices is it sufficient to gently tap the coin withyourfingernail. 6a. If the sound matches the expectedresonancefrequencies of the selected coin, you will see a greencheck-mark.6b. If there is too much noise, or if the sound does notmatch theexpected frequencies, then you will se a red cross. 6c.SomeAndroid devices have microphones which are unable to recordhighfrequencies above ~10kHz. If the app detects two out ofthreeexpected frequencies, it will indicate this with thefraction"2/3", and report that device limitations might be thereason whythe last frequency was not detected. 7. Some practice maybe neededto produce a clean enough sound from the coin. The appissound-activated, you can tap the coin again to do anothertest.Needed permissions: Record audio - To record the sound of thecoin.Storage - Necessary to enable "sharing" of testresults.Disclaimer: There are no guarantees whatsoever regardingthefunction and accuracy of this app. There are many factorswhichcould cause this app to report false positive or falsenegativeresults. This app should only be used to complement othertestingmethods, not replace them. Forum thread for discussionsandinformation about thisapp:http://forums.silverstackers.com/topic-38955-android-app-uses-resonance-test-to-detect-fake-silver-coins.html