Ground Balance With Nel Tornado Coil

[miserman]

I have been trying the 12" X 13" Nel Tornado coil on the F75. While doing the Fast Grab Ground Balance I have noticed that it is sometimes stubborn to Ground Balance. It will sometimes stay on the number that is on the screen until I do the up and down motion 10-12 times I have tested this by manually setting to a high number, say 90, when I know the ground is in the 60-70 range. Then when Fast Grabbing,it will stay at that 90 number until i move it up and down 10-12 times as noted above. It seems to eventually get the number right. I have tried raising it higher above the ground when doing the Fast Grab but that doesn't seem to help. I have read that with the Nel,any ground that is below 40 requires a Manual Ground Balance. I could always do it manually to solve the problem and for piece of mind but I like the convenience of the Fast Grab. I'm not planning on making the Nel my every day coil, but would like to know if anyone has used it with similar results....Thanks for looking

 

[REVIER]

I have a Nel Sharpshooter and a Cors Cannon for my F70...tons of hours using both.
The F70 only has fast grab, no manual GB adjustments.
Personally I have never seen this or had any issue like this using either one.
These coils have been around for a few years and I don't remember anybody else posting about this subject, there might be some but I haven't noticed any.

Could be a defective product...it happens.
If you GB normally using other coils and it only happens with the Tornado that would be a big clue right there.
If you never had experience with a Nel I can see how you can easily assume this is just how Nel coils behave, but I don't believe they do or at least they shouldn't.

Again, overall quality is great on both brands from my experience and from what I gather on the forums but no company or factory makes 100% perfect quality on all their products.

I got a Red Racer coil that was bad out of the box, once, but the company immediately replaced it so stuff happens.

Hope you figure this out but in my opinion it seems like your coil and your detector might not be cooperating as well as they should be and that ain't right.

 

[miserman]

Thanks REVIER for your input. I did a 2nd Factory Reset and that seems to have taken care of the problem. I did the 1st Reset in the house when I first installed the coil but the 2nd Reset was done outside in the field. I wouldn't think it would matter where you do the Reset but anyway it is now Ground Balancing correctly....Thanks for looking

 

[REVIER]

Glad you got it worked out.
Another tip....it does indeed matter where you do a reset as you discovered but there is more.
For those of us that use an F70, Patriot or an older F75 with no DST many have discovered that at sites that are high in EMI doing a factory reset AT THE SITE many times will mitigate that issue and calm down your detector...a lot.
Don't know why this works but it does.

Also the Nel and Cors coils are better insulated than any of my Fisher factory coils to help shield them from EMI and make things much more quiet and stable.
In my heavy EMI filled sites they do, anyway.

 

[vlad]

with no problems. But Nel in the past has had problems with the loops not ground balancing,
and it crossed over into several brands. DD loops are a little trickier to design because the tx and rx each have a different number of windings.
This can have a big effect of resonance if not figured correctly. Throw in a less than perfect impedance match and you have big problems.
Manufacturing tolerance can be from precise to--awful, I have had more problems with this aspect than anything.
If your unit works correctly with the stock loop, and less than acceptable with an aftermarket design something is amiss.....you don't need Sherlock Holmes to recommend it be returned.
You get a chance check out the Mars offerings. (Lots of testing of multiple brands vs each other on youtube.)