Ground Balancing The GPZ 7000 In Salty/alkali Or Saturable Ground

[Jonathan Porter]

My recommended GPZ 7000 Ground Balance Method for Salty Saturable soils:

 

1. If no "Dust Iron" Ferrite, perform a "Walk and Sweep" at start up or after a "Reset Audio and Detection Settings" via Quick Start. I highly recommend you perform this in ground that is not too waa waa (salty) and keep the coil above 30 mm to avoid saturation signals.

 

2. If you have a "Dust Iron" Ferrite and the area your in is Salty, then perform the Octopus sweep over the Ferrite laying on the ground but limit the speed of the sweep to avoid salt signals and also minimise the amount of sweep distance (tighten the sweep up).

 

3. Once the above procedure has been performed go into the "Ground Balance Mode" menu and select Manual, this will then lock the GB so that Saturation and Salt signals do not affect the GB after that point. You can configure the USER button to take you directly to the Ground Balance mode menu option to save on time if you like.

 

4. Go detecting just like you would with a GPX 5000 in Fixed Mode using Fine Gold or Enhance. If you feel the need to ground balance place the "Dust Iron" Ferrite on the ground and perform the Octopus sweep for 3 to 5 seconds or until the unit is quiet (this should be checked regularly). There should be minimal or nil noise over the Ferrite but you need it there once the Quick Trak button is pressed in to get a good GB even if the Ferrite part of the GB is still good. For those without a Ferrite you should do a mini "walk and sweep" with Quick Trak held in, preferably where the salt signal (waa waa noise) is less, keeping the coil above 30mm to avoid Saturation signals.

 

Notes: By using Manual mode you stop the Salt and Saturation signals from interfering with the GB, salt signals can throw the GB out if in tracking mode, this also happens on a GPX 5000 when in Tracking mode. If the detector is exposed to strong Salt and Saturation signals when the Quick Trak button is depressed you could end up with an atypical Ground balance which is not good for effective metal detecting.

 

People need to take into consideration the GPZ's ability to sample very early, due to this it's more aggressive on Salt signals and Saturation signals (probably by a magnitude of 2 or more but not as bad as a VLF), hence operators need to keep that in mind in Alkali or Saturable ground.

 

By using Manual mode and attaining a good GB at start up and maintaining it by regularly checking with the Ferrite during the session you will not have to worry about Salt or Saturation signals affecting the GB. A slower sweep speed has always helped with salt so be prepared to slow down, salt signals vary from ground to ground even over small distances. If unsure it is salt your dealing with just lift the coil to waist height away from your body and listen for a faint to loudish broad signal, if so Salt is present.

 

JP

 

[DDancer]

Well I'm down here near Kal and seeing a lot of saturation in area's that I don't feel are salty.  I'll give it a go.  Gotta see if I can talk the ML dealer here into giving me a Ferrite~ seems ML only told him to give them to people he dealt with and the bead only came out just before I left the states.

Curious how the bead will help with black as ironstone hills.

Partner and I have been calling the saturation signal the "howlies" and to date only dumbing up the machine helps.  Try manual next.  Funny pumping the coil to check balance in the howlies does not show any out of balance condition most of the time...

Any thoughts or is this just riding in line with what is being said about how auto is grabbing the salt as it sweeps to howl...?

 

I'll catch up with this post when I get back into town.

Thanks.

[Norvic]

Is there any benefit using the ferrite in non salty soils? but of course leaving the GB in tracking as per norm rather than manual as per salty.

[1515Art]

JP, thank you very much. really helpful. I was in Lovelock NV today, but skipped going out to rye patch because it rained pretty hard all night long and was still sprinkling this morning. I'm going to try again next week and if I hit any of the hee haa s it will be nice to have a way to deal with it, guess this could also be the answer on a salt water beach as well.

[Sourdough Scott]

So, what can we use in place or substitute in place of a dust iron ferrite? 

I have no idea when our dealers can get them and then to us?

[Steve Herschbach]

Have you contacted your dealer? They should have them any day now.

I must be the only guy on the planet not having any particular issues with my GPZ. I just go use it, it finds gold. I don't expect much difference using the ferrite. JPs suggestions will only reduce salt issues, not eliminate them.

I keep the volume fairly low, swing slow and very evenly to turn the moan/groan of the salt response into its own sort of threshold. Any break turns out to be a target just like a break in the regular threshold. I am not entirely certain I want to eliminate the salt response. JP has really helped me by encouraging me to turn off the tracking in the salt, which is probably detuning my salt/gold response.

[Sourdough Scott]

Yes, have contacted the dealer. Should be getting them soon. Otherwise I have had zero issues with my 7000. But want to have a ring if needed.

[Steve Herschbach]

Well the point then is do not be in a rush to use a substitute since Minelab specifically recommended against that. More chance of making it work worse instead of better if there is no problem needing fixing.

But do get one - they are free! I am not sure how much they will help but Chris and I have been assured they will not hurt.

[Norvic]

My dealer sent me a ferrite free, no prompting. He is on the ball, always has been. I have not used as yet, don`t see the need, unless advised otherwise, and JP has not answered my query as yet in regard to that. C`mon young fella I won`t bite. Very happy with the GPZ, I suggest GPZ owners give Sandys Bognene settings a trial you will be pleasantly surprised.

[nvchris]

Norvic,

 

Can you link to Sandy's settings?