Okay fellow detectorists here's the scoop on today's hunt (12:15 to 5:45pm) and some info on an air test that I did with the 8 inch coil and the 11 inch DD coil. First the hunt... went to the park in town after dropping my nephew off at work and had decided before hand to hunt and area that is really not used very much anymore. It is a large field in front of a baseball field that is still used by the local teams. I pretty much wandered around aimlessly, Sens @ 92 and as low as 50, due to EMI, Disc at 20, GB @ 65-72. The reason for this was to check and learn my new 11 inch DD coil. I figured the best way for that to happen was to take it out where there is a minimum amount of trash, so I could concentrate on just good targets. Well the joke was on me as you can see from the pictures. Don't get me wrong, I am not complaining in the least. I think the DD coil does a great job, there are just a few things I had to get used to. 1. The coil, as I have read else where, loves bottle caps. I did learn that on some of them the Gamma would switch from dime to quarter and back. These would always be caps. Some would ring up as pennies, some would ring up as quarters. I have never dug so many bottle caps as I did today. But that is part of the learning process. 2. It seemed to me that the pinpoint mode would change location on the coil depending on what type of target was under the coil, and the target would be a little deeper than indicated. I was able to recover all targets that I attempted to find, but some took a little longer than I am used to, even with my pin-pointer. Again, part of the learning curve with the new coil. Over all I am very happy with the performance with the Gamma and the 11 inch coil. I recovered the deepest targets that I have ever dug today and the Gamma Identified them as good targets. 2 copper pennies at 6 to 6 and a half inches (measured by using the length of my digging tool), and a quarter at 7 inches, measured the same way. I was beyond tickled. Even if they weren't wheats and the quarter wasn't silver, I was still very impressed. This is a new experience for me and it was great. I included the picture of the trash cause I wanted everyone to see what a lot of people don't realize. All of those trash targets showed up as good targets on the detector. Now If I had gone to a place that is used more frequently, I may have recovered more coins. I still can't get over the fact that I didn't get 1 nickel today. Every nickel target was either a pull tab or can slaw. This is the same with my Pioneer 505. I have only dug 18 nickels this year, compared to 45 quarters, 64 dimes, 208 zinc pennies, and 60 copper pennies. It just seems that there aren't that many nickels to be found, cause I dig all nickel signals, because I found my only gold ring under a nickel signal. On to the air test.
These are the results of my air test on my Gamma 6000 with the 8 inch round coil and the 11 inch DD coil. The first number in each column is the maximum distance that the Gamma would ACCURATELY identify the target. The second number is the maximum distance that it would SOUND OFF on the target. As you can see, the concentric coil more than holds it's own against the DD coil where depth is concerned. Where the DD coil beats the round coil is in the size of the magnetic field at depth. It maintains the length of the coil at depth whereas the the round coil field kind of looks like an ice cream cone that starts at the coil and narrows at depth, so it would be easier to miss a deeper coin the further away from the coil it is. What really surprized me is that the disc mode identified deeper/further away than the all metal mode. This is opposite of what happens with my Pioneer 505. Maybe Monte will chime in and help me to understand why this is. Possibly it has something to do with the test being conducted in the air instead of a ground full of various minerals and stuff. Whatever it is , it was unexpected.
8 inch Concentric coil
disc mode All Metal mode
nickel 7" - 11" 6 1/2" - 11 1/2"
penny 7" - 11 1/2" 6 1/2" - 12"
dime 8" - 11" 7" - 12"
quarter 9 1/2" - 12" 8" - 12 1/2"
11 inch DD coil
nickel 7 1/2" - 11 1/2" 5 1/2" - 12"
penny 7" - 11" 6" - 11"
dime 8" - 11" 6" - 11"
quarter 9" - 11" 7" - 11"
Sensitivity at 92 which is as high as I could go before it got really unstable. There was a little chirping at 92. No ground balance, no Disc. I hope these results help shed some light on the coil situation. I am very impressed with the performance of the stock coil. I learned a lot by performing this test on my own equipment and hopefully it will help some others out there in cyberspace. I plan on taking my 505 to a small school campus and the park tomorrow for a coin hunt. I will post result in the bounty hunter forum if anyone is interested. Thanks to all for reading and Happy Hunting.
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These are the results of my air test on my Gamma 6000 with the 8 inch round coil and the 11 inch DD coil. The first number in each column is the maximum distance that the Gamma would ACCURATELY identify the target. The second number is the maximum distance that it would SOUND OFF on the target. As you can see, the concentric coil more than holds it's own against the DD coil where depth is concerned. Where the DD coil beats the round coil is in the size of the magnetic field at depth. It maintains the length of the coil at depth whereas the the round coil field kind of looks like an ice cream cone that starts at the coil and narrows at depth, so it would be easier to miss a deeper coin the further away from the coil it is. What really surprized me is that the disc mode identified deeper/further away than the all metal mode. This is opposite of what happens with my Pioneer 505. Maybe Monte will chime in and help me to understand why this is. Possibly it has something to do with the test being conducted in the air instead of a ground full of various minerals and stuff. Whatever it is , it was unexpected.
8 inch Concentric coil
disc mode All Metal mode
nickel 7" - 11" 6 1/2" - 11 1/2"
penny 7" - 11 1/2" 6 1/2" - 12"
dime 8" - 11" 7" - 12"
quarter 9 1/2" - 12" 8" - 12 1/2"
11 inch DD coil
nickel 7 1/2" - 11 1/2" 5 1/2" - 12"
penny 7" - 11" 6" - 11"
dime 8" - 11" 6" - 11"
quarter 9" - 11" 7" - 11"
Sensitivity at 92 which is as high as I could go before it got really unstable. There was a little chirping at 92. No ground balance, no Disc. I hope these results help shed some light on the coil situation. I am very impressed with the performance of the stock coil. I learned a lot by performing this test on my own equipment and hopefully it will help some others out there in cyberspace. I plan on taking my 505 to a small school campus and the park tomorrow for a coin hunt. I will post result in the bounty hunter forum if anyone is interested. Thanks to all for reading and Happy Hunting.
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