Jump to content
Jonathan Porter

My Personal Method Of Ferrite Balancing

Recommended Posts

2 hours ago, cobill said:


Is this Treasure Talk the source for your chart, and if so, the software update according to ML fixed the ground balance issues...or did it?

"With the update, we have improved the ground tracking so that the detector is much less susceptible to the typical events that will cause the tracking to deviate from the ideal level."

"detecting your pick will still cause an audio response but it won't impact the tracking."

"there will no longer be a need to continually re-ground balance with the ferrite, unless perhaps moving to a completely new area."



The more I read about GB, the more confused I become! Really appreciate JP's posts.:biggrin:



  The pic was from the Minelab website, just as you show in your link. I agree with what JP says in the beginning of this post :

"I also recommend users adopt the GB configured to their USER button approach and to go into Manual mode when checking deep targets or committing to dig, leaving the GPZ in Semi-Auto will allow the GB to drift either through exposure to the pick whilst digging or just general drift through the coil not moving, either way the GB will be out which is not obvious unless you pump the coil. "

The update seemed to make the detector more stabalized with the semi auto mode in my opinion, as that is what I always use, but I notice it still drifts a little, I will have to rebalance with ferrite maybe every 2-3 hours. But it could just be different soil conditions, EMI (which I notice increases during the day), Saturation, Pick, Coil not moving,  blah, blah blah,  who Knows for sure ???? I get like you, more confused, as more things are introduced....

  One thing I was experiencing a lot on the Yellow T-130 ferrite ring, was it would still sound off a little when balancing to it (It would not dissipate out all the ferrite noise) , then I moved to another Ferrite that was in Minelabs specs, and it works great so far. Just personal experiences, Im sharing...

  • Like 1

Share this post

Link to post
Share on other sites

It really isn’t that complicated. Ferrite balance is performed with the Ferrite, Semi-Auto is preferred because then the ferrite balance can’t shift unless the detector temperature shifts. Ferrite balance is not dependant on ground but instead dependant on the detectors temperature, X signal is in the ground in varying degrees, the detector will react to the X signal if the Ferrite balance has not been performed correctly or if the coil generates signals off the Ferrite that cannot be balanced out. If the Ferrite balance is out the resultant X signal will blend with or elevate ground signals potentially causing spurious indefinable signals and generally make the detector noisier to listen to, all of this will affect depth.

It takes 20 seconds to perform a GOOD ferrite balance, in Normal Ground Type mode the detector reacts to Ferrite signal much more aggressively as it does with ground signals and salt and saturation signals, as such I HIGHLY recommend using Semi-Auto to avoid these things throwing the Ferrite Calibration out.

There will always be a tiny amount of residiual signal off the Ferrite, especially in the very centre most sensitive part of the windings. This is normal behaviour, so long as there is NOT a HUGE or LOUD signal off the Ferrite.





  • Like 4

Share this post

Link to post
Share on other sites

Oh dear, now I need a thermometer???

Jonathan, what temp, how much change?

 I don’t think I knew about this...or my little brain leaked....


  • Haha 3
  • Oh my! 1

Share this post

Link to post
Share on other sites

I'm still unclear on why auto tracking is not sufficient on the GPZ, especially for milder soils here in the US.

There was discussion in 2015 how it was much faster and more sophisticated than the GPX auto tracker and so should be used, but now it's somehow too slow again after semi auto came out..? My experience has been it tracks fine in my ground and I simply pull the QT trigger if it's taking more than a second or two to catch up to me. I detect pretty fast and it's never slowed me down.

I thought the GPZ was supposed to "remember" the ferrite in any tracking mode? If not, then why use the ferrite at all in auto at all since it'll just be tracked back out a few minutes later?

Seems to me Semi Auto is best used in places with a lot of ferrite component in the ground - like Australia. There aren't a lot of places like that here in the US. Or potentially in places with a lot of salt since JP has said a number of times that salt throws X balance off, but that confuses me too since it looks like salt should be part of the G component of tracking where Semi Auto is the same as Auto anyways and there has never been much talk or definition about G or how exactly salt messes with X balance without being part of X...

  • Like 3

Share this post

Link to post
Share on other sites

Hey Jasong,

   I have been using Auto since the unit has been released and found plenty of gold.  I guess I could have missed stuff, but I would never know.  In Minelab's instructional manual, I'm sure they recommend running in manual.  I found in the manual where Minelab states this -


Auto ground balance automatically tracks the ground mineralisation levels and adjusts the ground balance as necessary to maintain stability and detection depth. Auto is the recommended setting for Ground Balance Mode

That being said, I tried Semi-Auto a few times in the past and didn't notice much change.  I tried it again today, but believe it or not, it seems to really work well (go figure).  

I ran Semi-Auto all day, used the Ferrite ring twice.  I pumped the coil up and down throughout the day, no real change in threshold.  

Going back to what JP said originally - why can't you just run in manual ground balance all the time, like many would do with fixed ground balance on the GP or GPX units?  I have never went into Manual balance on the GPZ 7000, so I'm clueless on how it performs.  Would you use the Ferrite Ring also in Manual? 


I also recommend users adopt the GB configured to their USER button approach and to go into Manual mode when checking deep targets or committing to dig, leaving the GPZ in Semi-Auto will allow the GB to drift either through exposure to the pick whilst digging or just general drift through the coil not moving, either way the GB will be out which is not obvious unless you pump the coil. 


  • Like 1

Share this post

Link to post
Share on other sites

Rob, did you try Semi Auto in the same places that you ran Auto in the past without noticing much difference or were they different spots this time? Can you elaborate on the ways you noticed Semi Auto method working better this time? 

Were you in a place with some amount of mineralization or was it fairly mild? Your general part of AZ is so variable in the intensity of ground mineralization that it's hard for me to guess, I've seen the gamut from requiring Difficult at 10 sensitivity to being able to do Normal full bore, all within 5 miles.

Share this post

Link to post
Share on other sites

Quick-Trak equals Forced Fast GB on both Ferrite/X Balance and G balance simultaneously, so it is not advised to use Quick-Trak unless the Ferrite is present. In Semi Auto Mode Ferrite/X balance equals Locked Ferrite/X balance but slow tracking G balance, hence why I slowly pump the coil after releasing Quick-Trak and why I continue to pump the coils occasionally during detecting sessions because it is slowly tracking the G balance. In SEMI-AUTO MODE Ferrite/X balance is LOCKED!!!

G balance changes often, Ferrite/X balance only changes if any of the following happen, Big temperature change of the electronics when in any mode (Auto, Semi-Auto or Manual), Saturation signal when in Auto Mode, Salt signal when in Auto Mode. When in Semi-Auto Mode Saturation and Salt cannot effect the Ferrite/X balance only the G. When in Manual Mode everything is locked unless Quick-Trak is triggered, however it is strongly advised the Ferrite be present when doing so.

I can’t be any clearer on this subject now, hope this makes sense. Remember in SEMI-AUTO MODE the FERRITE balance is LOCKED and can only change if the temperature of the electronics moves or changes a lot. Usually this happens mostly in winter between first start up and about an hour later as the electronics go from dead cold to operating temperature. In SEMI-AUTO MODE ground cannot effect the Ferrite/X balance only the regular G balance.



  • Like 2

Share this post

Link to post
Share on other sites

Hey Guys,

   Jasong - Yes, I was in the same area, but not the exact location.  In Semi-Auto the unit seems to run smoother from what  I noticed vs. Auto mode.  I used to always run Auto, but found at times it got noisy even after a ground balance with  the Ferrite. 

JP - No question you are an expert on all this, but I can tell you, it' down right confusing.  You wouldn't believe how many emails I have gotten from this thread, asking me if I really understood all this X-balance, G-balance, temperature change, using the Ferrite or NOT, what mode to be in, and should you use the Ferrrite.  Most of all the customer have stated, "it don't show any of this in the instructional manual?"

I must tell you, the customers that were on fence about buying a GPZ 7000 just jumped back.  Reading this for a new customer, or someone thinking about purchasing is way too confusing.  

I'm real surprised Minelab hasn't clarified any of this.  If it wasn't for you, most of us wouldn't have a clue about all this technical stuff.  

  • Like 2
  • Thanks 2

Share this post

Link to post
Share on other sites
1 hour ago, Jonathan Porter said:

G balance changes often, Ferrite/X balance only changes if any of the following happen, Big temperature change of the electronics when in any mode (Auto, Semi-Auto or Manual), Saturation signal when in Auto Mode, Salt signal when in Auto Mode.

I've seen you say this often. If this is true, how is salt affecting the ferrite balance? Salt is not a ferrite. Salt is a conductor, like gold. So, will gold and other conductors affect the X balance too if salt does?

Also, what I can't wrap my head around is this:

1.) Ferrite is X.

2.) X is in our soils, thus ferrite is also in our soils.

3.) Semi auto tracks to the yellow ferrite presumably because that component isn't in our soils, and we now keep X constant to the ferrite and not our local changing soils.

4.) X continues to change in our soils but our X value in our detector stays steady. IE: not tracking the ferrite in the ground anymore

So, how is that not causing noise as the soil's X component changes yet our detector is staying tracked to the ferrite?

Why not just keep the detector always configured to the ferrite by adding some kind of offset into the firmware if it needs the ferrite data and not our local X soil data?

  • Like 1

Share this post

Link to post
Share on other sites

And …. Saturation only affects X balance, not ground balance. 

And …. Semi Auto locks the X balance when you release the button (I proved this well in my testing) but allows the ground balance to track slowly. 

As an added note, my 14" coil was smoother in Semi Auto, than when I used to always have it set to Auto.  As JP has mentioned in the past, if you don't want to use the Ferrite, then he suggests Auto, but if you use the ferrite, we should lock it in with SemiAuto.

we will figure this out, yet...

As I questioned on a different link, what exactly saturation is …. still has me confused. 

Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Similar Content

    • By Northeast
      'ello, 'ello, 'ello, what's all this then?
      Wonder how the dongle is done?

    • By Jonathan Porter
      Have a video on Audio Smoothing up on the Minelab YouTube channel for those interested.
      Hope this helps
      Prior thread in subject
    • By Steve Herschbach
      The Minelab GPZ 7000 audio Smoothing function was directly derived from the Stabilizer control used on the GPX series. From JP at http://www.detectorprospector.com/forum/topic/715-gold-i-found-in-victoria-with-the-gpz/?p=6424
      "On the subject of Audio Smoothing: Off on the GPZ = 20 on the GPX 5000, Low equals 15 and High equals 10."
      JP at the link referenced obviously prefers Smoothing to be left off. Some people are experimenting with higher audio smoothing settings combined with either hotter Gold Mode settings or higher Sensitivity settings or both. I think this is a good thing so do not go thinking it is "wrong". There is no right or wrong per se, it is all about what works for each prospector and their personal tolerance for noise or the lack thereof. Experimentation is good.
      I thought it would be informative to copy what the GPZ manual (page 66) has to say about the Stabilizer control. Warning: the GPX Stabilizer control is backwards. The highest setting if 20 is the off position. Lower numbers increase smoothing. So the GPZ at off is same as GPX at 20 (off). Note that the GPZ High setting is the same as the GPX default setting of 10. The default for the GPZ 7000 is Low Smoothing which is the equivalent of a setting of 15 on the GPX.
      One final note. RX Gain as referred to on the GPX is the same as the Sensitivity control on the GPX.
      From the GPX manual:
       I guess I should say that my preferences tend to follow JPs - I run with audio Smoothing off under nearly all circumstances. But I wanted to make this post to create a thread on the subject as it is very clear people are having success with other ways of thinking and again, I like out of box thinking. Lunks settings at http://www.detectorprospector.com/forum/topic/830-lunks-zed-settings/ are at the other end of the spectrum. I also liked Jason's observation on the subject at http://www.detectorprospector.com/forum/topic/827-minelab-video-gpz-7000-ground-type/?p=8276
    • By CCRV
      Hey guys, 
      I hate being the guy asking for help on the forum. But, I'm really struggling and hope some of you with more experience on the GPZ might be able to share some insight.
      So, here's the scenario. I have what I think is an old equipment pad I've been working. I've nicknamed it my "trash patch" since it is just hammered with trash, probably why it doesn't appear to have be detected much even though close by areas have been beat to death. I found my first nugget in there with my GPZ at about 8", The problem, so much trash I couldn't even keep a single target under the 14" coil. I went back this week and spent 2 1/2 days (sun up to sun down) with my GB2 cleaning about a 2500sf area of trash. I can't begin to know how many targets were removed, but I can tell you my legs are so sore from that many squats I can barely walk today. Once I got the area clean, I was super excited to get back over it with the GPZ and see what I could find.
      And, here's where we get to the help part. This entire pad has basically been built with about 3" of crushed hotrock. I thought getting the trash out was the biggest issue, but it wasn't. I can't figure out setting on the GPZ to get through the top layer. Either it just wobbles and whines all over the place, or you choke the settings down so hard it won't pick up anything. I can't find a working medium. Short of racking and shoveling 3" of rock off this area, which moves way outside the bounderies of enjoyable hobbie for me, I'm not sure what to do.
      Anyone have some detector settings I might try, or other ideas would be greatly appreciated.
      Attached are 8 little micro nuggets I pulled off the surface cleaning trash with the GB2. Everything I have got more than 2"s below the rock layer has been larger.
      Thx, Beau

    • By jasong
      I'm not sure if it's coincidental but since the update I've run into a number of areas that cause a strange oscillation on the GPZ.
      Basically, I can set the coil on these pieces of ground and not move it at all and it will just go "wee-woo-wee-woo" constantly and loudly as if there is a target underneath, it never balances out, manual or auto. Rebalancing over the ferrite does not seem to affect it, wether the ferrite is over that spot or away from the spot. 
      At first it was small spots and I thought it was EMI related, but now I've found entire washes that do it, yet the next wash over is fine. I was inclined to think it was due to salt, but there is so little salt around here that I went ahead and tasted some of the dirt (yep) and it wasn't salty. Usually I can taste salt if its bad enough to interfere with my machines. These washes have a lot of black sand and a lot of banded iron formation chunks laying about. usually running in normal and switching to difficult takes it away for the most part but sometimes it's still there.
      Just odd that it never balances out. Has anyone else run into ground like that before? Most bad ground won't sit there and oscillate if you stop moving the coil even if its bad enough to not balance out.
    • By normmcq
      When the upgrade first came out, a lot of ZED users were reluctant to change. I for one, thought if it was recommended, I should do it. I personalty believe it is more stable and more sensitive. I started to find very small pieces of trash in some areas that were virtually target free and some gold that was missed by some competent ZED users. The seven smaller pieces were found at Rye Patch and the others were found close to home in a very pounded area with all kinds of detectors. These were all found after the upgrade
  • Create New...