Nox Series 10x5 Instability

[RickUK]

I was using my 10x5 coil on my Nox last sunday,the ground conditions are about as highly mineral as you can get and also very short barley stubble,i tried using the coil for a few hours but because i was near a giant pumping station the Coiltek coil could only run with sensitivity down to about 16 although it was reasonably stable i did not feel happy with it.

Changed over to the 6'' coil and Bingo and it was running as smooth as silk and also able to run the sensitivity back up again,i think the trouble with the 10x6 running erratic on the day was this massive pump station near the field,i had to run it in multi freq due to the black mineral soil.....only found a few roman coins any before the heat beat me at about 13.00 and came home again.

In normal conditions i would think it would run very stable.

[Wh1sk3y]

I went out this last weekend with the 10x5. Hiked out into the tailings turned the machine on lowered sens till it stopped chattering which was 16. Set the machine down and threw rocks off of the bedrock for 15 or 20 mins. The coil was super quiet so I slowly began raising sens back up to 18. Still quiet. Found a couple pieces in the .2 to .4 range. It seems like it was worse at sunrise and gets betters as the sun gets higher in the sky. My area has no cell service or source of emi, so I suspect it was emi from the sun? As the day went on I worked back up to sens 20. I wonder if was the sunrise conditions or the coil needed to "warm up"? From now on I'll start with the 6" coil and switch as the day goes on. Thanks all for the advice.