THIS IS FROM A STORAGE UNIT SO I DOENT KNOW HOW TO USE IT BUT I HUCKRD THE CABLES UP TO A BATTERY & TUTCHED THE WIRES TO GETHER & THE NEEDLE MUVED BACK & FORTH!
THATS ALL THE TESTING I DID! I THINK ITS COLL THAT THAY PUT A SQAER MAGNIFIEING GLASS ON IT!