chatter with 12.5 coil

[fongu]

I went to my local church and tried using the 12.5 coil that came with my GTI-2500 and I got chatter everywhere I went. The foundation of the church must be
embedded with concrete reinforcing wire. I came home and intend to go back with my 9.5 coil and see if the large coil was getting overloaded. Any suggestions? I found one 1976 dime in the gravel area where cars park for church service. I got a lot of hits that seemed like coins, but continued to be overwhelmed by chatter. I also noticed the top mark that identifies whether dime, nickel or penny seemed to hang up all the time and I would have to push the operate button to get it to sound off when scanning for coins. real slow to respond. this church is over 100 years old and should be capable of producing lots of coins, but I must not be doing something right.

 

[cwilk]

Check that the coil wire is fairly snug around the shaft and that the connection to the box is good. Also try lower sensitivity.

If neither of those work I'd start troubleshooting. Try some air tests in an area far away from any metal, wires, or anything else that might cause interference. Not indoors. See if you can get it to work properly at another site. It could be mineralized ground. I use the big coil a lot, in fact it hasn't been off my machine for about three months. I had a hard time getting used to it but now I'm pretty proficient with it. I always have trouble detecting in gravel with all of my coils. I stick to the grass most of the time. I think in my area a lot of salt and chemicals accumulates in gravel left over from snow removal.

Good luck. Let us know,

Chris

 

[Uncle Willy]

Try lowering your sensitivity to 6 or 6.5. Run your coil at least an inch off the ground.

Bill

 

[Groundshaker]

Look overhead for power lines (EMI). reduce gain (sensitivity) .

I went to my local wally world and picked up a backpack.I keep my extra coils,batteries,digging tools,pouch,belt and some jerky and a bottle of water. When it's detecting time,i grab my detector(s) and my backpack and go....

 

[fongu]

I have the sensitivity at 6.5 and I will try using it elsewhere. It chatters all over the place on the grass. I intend to try the 9.5 coil tommorrow after church and see what happens.