برترین 9 برنامه مشابه به Theory of Machines and Mechani
Bullion Test 1.14
This app offers a cheap and easy to use method to helpdetectfakebullion coins, by examining their resonancefrequencies.Theresonance frequencies of an object are determined bytheobjectsshape and material. If the shape and weight of a silvercoiniscorrect, but the material is not actually silver, thenaresonancetest could detect this. This is also known as a"ringtest" or"ping test". Unlike the manual "ring test", this appdoesnotrequire that the user knows exactly how each coin shouldsound.Theapp will also detect resonance frequencies above the rangeofhumanhearing. This youtube video shows how to usethisapp:http://www.youtube.com/watch?v=5pZnqp3bl3A Currently,thesecoinsare supported: 1oz American Silver Eagle 1oz SilverBuffalo,flatedge 1oz Silver Buffalo, reeded edge (Sunshine mint)1ozLibertySilver 1oz African Wildlife Elephant 1oz Silver MapleLeaf1ozPhilharmonic 1oz Australian Kookaburra 1oz AustralianKoala2ozAustralian Lunar 1oz Chinese Panda Swedish100krcommemorativeSwedish 5kr 1954-71 Morgan and Peace silverdollars1oz Krugerrand1oz Australian Gold Kangaroo 1oz American GoldEagle1oz GoldVienna Philharmonic 1oz Gold Lunar 1oz Gold Buffalo1ozGold MapleLeaf $20 Double Eagle gold coin 20 Franc goldcoinBrittishsovereign gold coin There is also a "generic" featurewichsupportsALL .999 1oz silver coins with diameter 36-42mm. Justenterthediameter of your coin, and the app willautomaticallycalculatewhat it's resonance frequencies are. How touse this app:1. Forbest results you should perform this test in areasonablysilentroom. Some electronic devices may producehigh-pitch noiseswhichcould interfere with the test. 2. Select thetype of bullioncointo test from the drop-down list. 3. Press themicrophone buttontostart the test. 4. Blue lines indicate theexpectedresonancefrequencies of the selected coin. 5. Balance thecoin onyourfinger, near the microphone of your smartphone. Tap thecoinusingyour fingernail, or use some hard object. Do NOT use asecondcointo tap the first one, since the sound from the secondcoinmayaffect the results. The sound level required dependsonthesensitivity of the microphone in your Android device.Formostdevices is it sufficient to gently tap the coinwithyourfingernail. 6a. If the sound matches theexpectedresonancefrequencies of the selected coin, you will see agreencheck-mark.6b. If there is too much noise, or if the sounddoes notmatch theexpected frequencies, then you will se a redcross. 6c.SomeAndroid devices have microphones which are unable torecordhighfrequencies above ~10kHz. If the app detects two outofthreeexpected frequencies, it will indicate this withthefraction"2/3", and report that device limitations might bethereason whythe last frequency was not detected. 7. Some practicemaybe neededto produce a clean enough sound from the coin. Theappissound-activated, you can tap the coin again to doanothertest.Needed permissions: Record audio - To record the soundof thecoin.Storage - Necessary to enable "sharing" oftestresults.Disclaimer: There are no guarantees whatsoeverregardingthefunction and accuracy of this app. There are manyfactorswhichcould cause this app to report false positive orfalsenegativeresults. This app should only be used to complementothertestingmethods, not replace them. Forum thread fordiscussionsandinformation aboutthisapp:http://forums.silverstackers.com/topic-38955-android-app-uses-resonance-test-to-detect-fake-silver-coins.html