Coil ground effects

[Jayray]

Has anyone every experienced very erratic behavior using the GP3500 in semi damp conditions (morning dew), hot ground and using other than a coil cover (i.e. chemical compound barrier)?

I was recently detecting in very hot ground and morning dew and my detector was acting very erratic, on the border of thinking the coil was bad or the detector was fried. Now, with this being said, I recently used an adhesive (poly type) to cover the coil instead of using a coil cover and was wondering if that might have any thing to do with it as well???

Here's the punch line, I tried another coil on my detector and it worked just fine (so that ruled out the detector) as well as another detectorist tried my coil on his machine and it worked fine on his (ruling out the coil). So, could it just have been the combination of conditions of the hot ground, combined with the morning dew and the adhesive covering? Any suggestions or comments...Jason ;)

(Some additional info: with the adhesive on the coil, the coil sits off the ground about 1/4 of an inch.

After some peeling off of the adhesive, thinking that might be the cause, I found some air pockets in the compound itself.)

[Seeker]

Moisture in or on the ground really enhances the iron minerals and the alkali you will see this more too when you are hunting in the tall grass and it is wet with dew. Sometimes it is junk inside your coil cover so I don't use them anymore but what some are doing is putting a two part epoxy layer on the coil to keep the wear down..... HH..Geo

[FlakMagnet]

Jayray,

I think you answered your own question pretty well.

The combination of things you describe seems like they

could make your detector behave strangely.

I don't know what the compound is that you are using as coil protection,

but I do know that the two part epoxy that George mentioned works very well.

Grubstake turned me on to epoxy a year and a half ago and I have used it

ever since...pretty much a bullet proof solution.

Hope I run into you one of these days,

Flak

[Jonathan Porter]

I would say it is a combination of air pockets and moisture in between the cover you used and the coil base which is causing the problem, if the conditions are hot and sultry it can be exacerbated even more. Sometimes this can happen with a crack in a plastic housed coil allowing moist air into the workings which then condenses out onto the windings when the air temps drop causing the coil to become noisy, yet when the coil warms up again the moisture burns off and the coil starts to work again. The best bet is to try and keep the area bewteen the coil and the skid plate as dry as possible with minimal air gaps also make an inspection every now and then to clean out any fine mineralised dust or soil as moisture combined with this can be problematic.

Hope this helps

JP

[Nugget Shooter]

Yep JP I agree and in these conditions removing the cover as Seeker mentioned will help solve the problem....

Bill

[joeforthegold]

Jay Ray,

Semper Fi Brother.

I have had problems with a noisy coil before and I turned the machine off and disconnected the chord going to the coil then re-wrapped the chord going to the coil making sure it was not in a bind any where. My experience has been that if the wire going to the coil gets in a bind it will false like crazy.

Thank you for your service to our great country.

Jezisek, J.V. Sgt. USMC 85-92

Joeforthegold

[garimpo]

Jayray....all or some of the "fixes" above may solve your problem...if not and you are still having

a problem...same or less....try putting your "soil" and "boost" switches in Normal...sometime

that will take care of the problem.....