Noisy 18.75 DD coil on a X-70

[Steve in Idaho]

Has any one had a 18.75 DD coil that gives a false signal every time it touches grass or sagebrush when in the prospect mode? I was running in the prospect mode, slight threshold, sens up to 30,and with tracking off. Also tried to turn down the sens but did not solve the problem. I then switched to my 10 1/2" DD coil and it worked with no problems, sens up to 30, auto GB with track off and I could rub the coil on the ground and push it through the sagebrush with no false signals. We were in the high desert country with the temp about 45 degrees and the soil was dry.

 

[BarnacleBill]

This is a guess from a tenderfoot that's never worked the desert.

The ellip HF coil when run at high Sens Prospecting mode will respond to the waving of your hand over the coil. My belief is that this is due mostly to the saline content of your body, sweat, blood etc.

I would not be surprised that in a desert environment, that the soil has a high salt content, not just chloride, but other salts concentrated through the evaporative process. If the grass or brush is taking that salt up and concentrating it even further, then a reaction from that coil would be expected.

The other possibility is static discharge. Dry environment, rubber sole insulated boots/shoes, polyester clothing, waving big plastic stick. The larger DD coil would be capacitively coupling/draining the charge better than the small coil to the soil as you walked along.

HH
BarnacleBill

 

[OldeTymer]

n/t

 

[Steve in Idaho]

Thanks BB, I think that I will see what Minelab has to say. You made a good point and it may have been the high salt content.