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GPZ 7000 Auto, Semi Auto, Manual ???


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What ground balancing mode does everyone use? Only reason I ask, is I recently saw a video with Johnathan Porter on Facebook, , where he got a faint signal, that ended up being a nugget. He mentions if he was in auto, passing over the target 3-4 times, more than likely the signal would have went away. 

  Now I hunt in auto, and I can't count how many times I've come across a faint target, and it went away after a few swipes of the coil. Now I wonder how much gold I've missed....?

Dave

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Dave, I hunt in semi-auto as Jp suggested ...

I have tried to ground balance out very small nuggets and could not...But, if he says it can be done then I believe...

Of course you can't know what you missed if you missed it.haha

fred

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I have not used an auto ground tracking detector that doesn`t track out some gold, the Z auto tracking is miles ahead of the SDs-GPXs which I found you could not trust to run in auto tracking, but even the Z tracks out some, not much but (unless as Fred suggest there missed?). Most signals it tracks out are mineralisation, just a very odd one gets through.

Set your user button to manual GB and switch to it each time you hit one of those iffy signals easy to do and soon you`ll gain confidence and go mostly with the repeatable signals. This is one of the features that sets the Z out from the PIs, it allows you to cover ground without being held up checking too many iffy signals. Now if only ML`d get rid of that pesky quick track button and replace it with a GB alternate between manual/auto button as per the PIs they`d make it even better, give us the option of taking that crappy process out if we wish.

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  • The title was changed to GPZ 7000 Auto, Semi Auto, Manual ???

Couple of things that need to be thought about with any auto GB but more so with the GPZ. An edge of detection target will present itself to the detectors electronics as potential ground noise so the Auto GB is going to mess with it somewhat, this is why I always move away from a potential signal response onto clean ground, center the GB under the coil, and then get the GB averaged again by carefully sweeping before moving slowly back in over the target zone. 

In the case of the GPZ and why you should use Semi-Auto GB over Manual (I'll discuss the differences between Auto and Semi-auto below), the GPZ has a dual receive coil design (super D or DOD as some like to call it), this coil design is difficult to make because the two receive windings have to be kept in phase, you the operator can easily throw the coil out of phase through poor coil control. Out of Phase means that one receive winding is generating a different response compared to the other. If you are working variable ground where the GB is very active the interchange between different GB scenarios can cause a tonal break in the threshold as one winding passes into the new GB scenario while the other receive winding is still in the old scenario, this interchange is heralded by a target like signal response which usually the Semi-Auto GB quickly deals with. If you are using anything less the Audio Smoothing OFF then you will generally not hear these small interchange responses as the filtering masks them along with faint edge of detection tonal target responses.

If you use Manual GB those interchanges will sound very target like forcing the operator to either check them out or if the ground is really variable ignore them through attrition! Either way your technically blind while the interchange signal is in effect, using Manual the interchange response is much more aggressive and longer in duration forcing a compromised on what targets are investigated, effectively leaving quite a large amount of undetected ground. A thing to note, quite a lot of nugget signals are nested in those interchanges of mineralisation.

The nugget in the FB video sounded like a broad very faint variable tonal response but experience has taught me to check these types of signals out, because I was originally in Semi-Auto GB the target response between the High/Low Low/High channels was interfering with the response, this caused the Lead In and Tail Out of the target to be extremely wide as the two channels fought each other, especially on the Tail Out (the only way I can describe this type of signal response effect is when two magnets are moved near each other with like poles, they repel each other). Setting the GB to Manual on similar ground nearby brought the target response more into the Low/High range focus allowing me to centralize the response and confirm it was indeed an edge of detection target. In this case the target turned into a deep 6 gram slug.

6 gram Nugget Dig

Differences between Auto & Semi-Auto:
Auto GB on the GPZ 7000 is doing 2 things at once, it is actively tracking the ground and at the same time is very slowly tracking any Ferrite like signals in the ground. Semi-Auto is only actively tracking the ground with the Ferrite balance being fixed.

I do not like to use Auto in the majority of ground types in Australia as we have a lot of ground conditions that interfere with the active Ferrite balance, one is Salt and the other is Saturation. If you follow the normal Ferrite balance procedure in Auto mode and then encounter salty or saturable ground the Ferrite balance will drift away from optimum allowing Ferrite signals into the signal response (assuming there are Ferrite like signals there). These signals add to the threshold and ground noise potentially masking targets or in a worse case scenario sound like target signals that disappear.

Semi Auto locks the Ferrite balance, so when you use the Quick-Trak button over the Ferrite the detector is actively looking for Ferrite like signals and trying to track them out (triggering the Quick Track button in any GB mode does this), when you release the button the detector locks the Ferrite balance so the only way any Ferrite like noise can get into the signal train is either through temperature changes or not having preformed a good Ferrite Balance in the first place.

Hope this helps
JP

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Thanks for the great question and the great responses. For whatever reason, I have not gotten around to doing the software updates on the GPZ. I run in auto, but I usually do some sort of scrape on most signals I get, sometimes a couple. I've been hitting signals on layers of black sand that disappear after a few scrapes. I also usual run really hot settings. I guess I need to do the updates.

Chris

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Picture was from last weekend out with Dave, we broke a skunk finally.  Dave good luck on your mission this weekend!

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Thanks Chris nice finds from last Sunday. There is about 7 grams of gold in a baggie from last Sundays hunt laying in the desert somewhere ☹️ Approaching about 1500 hours on the GPZ, I think Im moving to the Semi mode ... ? , thanks Steve, Jonathan, Norvic, n Fred for the great advice...

Dave

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Thanks Steve and Jonathan...nothing I do has been earned. Rather it is the wonderful work of Steve and Jonathan and of course many others that get me running somewhat correctly. If only I had days, weeks and years of continuous experience; rather than the odd week or day... 

fred

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1 hour ago, fredmason said:

Thanks Steve and Jonathan...nothing I do has been earned. Rather it is the wonderful work of Steve and Jonathan and of course many others that get me running somewhat correctly. If only I had days, weeks and years of continuous experience; rather than the odd week or day... 

fred

I hear you Fred you about the odd week or day, on my side, work sure does get in the way :)....

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