I know the GB Pro has a very fast recovery speed, but this evening, I found out just how fast it is. Was tired but bored after work, decided to wax and armorall my machine. I rarely flip it into discrim mode, but just for kicks, I decided to see how it'd do in an air test. Set gain to 100%, discrim to 40 and battery level was at the 2 bar mark with the 5" coil on.
Grabbed a rock that had some color in it (tested with 22k acid). The spot of color is approximately 5mm in length (see attached photo, rock still wet after washing off acid remnants). The ruler in the photo is graduated in millimeters. Swung slow just over the patch of rust and color, maybe about 2.5 to 3 feet/second. I really didn't expect much, but to my great surprise, GruntZipGrunt came thru my headphones!. Mind you, the "Zip" was very short, staccato-like, but crisp and clear. It was repeatable till I moved the coil about 1.5 inches away.
Most of you reading are probably coin/jewellery/relic hunters....but if your machine ever emits a short repeatable zip over a rock, consider applying a sledgehammer with extreme prejudice to the rock. There could be good stuff within!
Grabbed a rock that had some color in it (tested with 22k acid). The spot of color is approximately 5mm in length (see attached photo, rock still wet after washing off acid remnants). The ruler in the photo is graduated in millimeters. Swung slow just over the patch of rust and color, maybe about 2.5 to 3 feet/second. I really didn't expect much, but to my great surprise, GruntZipGrunt came thru my headphones!. Mind you, the "Zip" was very short, staccato-like, but crisp and clear. It was repeatable till I moved the coil about 1.5 inches away.
Most of you reading are probably coin/jewellery/relic hunters....but if your machine ever emits a short repeatable zip over a rock, consider applying a sledgehammer with extreme prejudice to the rock. There could be good stuff within!
