Part 2 The Negatives of the GPZ7000

Why does this detector go to high yield when you go to sever? I might wan't to hunt in General or extra Deep. My choice has been taken away from me because of the computer settings. it thinks that high yield is the better setting. I don't like that Hummm.
In Normal this detector picks up clay domes, hot rocks, charcoal and tree roots. Reminds me of the 2000 days. In difficult most are gone. Thank God. I know normal will get you more depth but at what expense. Digging hot ground all day. No way I like to detect in Difficult.
The 240 volt charger. If the climate you detect in is anything like Nth Qld 38c-49c then you may have a problem charging it. Sometimes you get a red light on the charger and it stops charging. This is to protect the charger and the battery one would think. This tells you the battery is too hot to charge. In hot climates the battery to be charged can feel hot before you put it into the charger cradle and will not fully charge due to the battery getting too hot.
Maybe need to put in fridge before charging. I don't know if this would be detrimental to the life of the battery. I think the charger needs to be redesigned with a cooling fan like the charger for the 2300.

Can't ground balance the detector on certain ground. Found some ground last weekend that I couldn't detect properly. The ground was disturbed and was silty and had been recently been rained on. Everything I tried I couldn't get it to settle. I can only guess that it may have been the salt content of the soil. Lifting the coil higher off the ground did help but the detector still didn't like it much. I have heard reports that it doesn't like salt lakes either like over WA. It could have been user error but I don't think so. JP can you please elaborate how I should go about detecting this ground with this detector as there is gold to be had.

Anyway that's the negatives I have found so far but the positives far out way the negatives. Why do I say that? I am finding gold the other machines left behind. I know I have been over these patches before with everything available. Still producing and in some cases making the patches bigger much bigger like 200m x200m bigger. I have used this detector off the patches and walked general prospecting picking up gold in the middle of nowhere. Bruce Candy was right when he said it will reopen the goldfields. Take it for a walk and go prospecting see if I am not right. May all your dig holes be golden.

Why does this detector go to high yield when you go to severe?

There is a problem in these designated timing setting names as we assume certain things about them that may or may not be true. I would liken your question to something like "How come I can get gold deeper in Sharp or Coin/Relic than I can on Sensitive smooth on my 5000?"
There is a reason why mild ground settings in general get better depth. Ground balance on metal detectors is an effective loss of sensitivity. Now its not a simple loss like turning down gain or raising the coil, but the more ground balance you need to use, in a general way the less sensitivity your detector will have. That is why very mild ground settings like coin/relic or sharp, you can get gold deeper than you can in extreme bad ground settings like sensitive smooth - so long as the ground mineralization is suitable. (I've never actually found any ground in a gold field that could run Coin/relic here in the states). In severe for the GPZ you are getting a timing that is for the worst ground, and you are not going to be getting deep gold, in a manner similar to sensitive smooth on the 5000.
So in the same way that you don't want to use sensitive smooth all the time if the ground tolerates more aggressive mild ground settings, you don't want to run severe unless you cant get by with anything else. On the other hand, you don't want to run coin/relic on your 5000 because it is more sensitive in spite of the fact that the machine screams, moans and whines all the time. The same way, you don't want to run normal on the GPZ because its more sensitive if it makes the ground constantly sound off, lights up hot rocks, etc.

I will say as far as recently rained on moderately salty ground (not a salt flat but poorly drained ground with some salt) - I had similar issues. I am told to try difficult and deep. It may not solve the problem totally but is the best setting for that type of ground.

in some cases making the patches bigger much bigger like 200m x200m bigger.

This is one of the as yet little discussed advantages of this machine. Yes, for known patches it makes them bigger and allows hitting gold on the edges, expanding the edges significantly. What I am thinking of is in new patch hunting. If one is wandering around, with an expanded patch, one has a larger target to walk across and hit a nugget, making a new patch easier to find and see because its now larger and you can hit a nugget on the edge and see the patch more readily.

Chris I wet to sever because I couldn't get the detector to become quiet. High yield I thought was for looking for small gold. General for most gold sizes and extra Deep for 50 gram plus nuggets. My 5000 purred over this ground that the 7000 doesn't like. As you say extra deep may help. My question is in this setting will the 7000 see and find gold that the 5000 did not see. I am sure the Zed sees gold the 5000 didn't see in General/Normal and General/Difficult. These settings after using the detector I believe to be optimum settings. I prefer to detect in general than high yield as you cover a better size nugget range. One would think going to sever high Yield or sever extra deep the loss of depth and sensativity would neutralise any advantage the 7000 had over the 5000 in this type of ground.

Question

If your in General/Difficult and want to switch over to say General/Normal , you have to do the BG for the next mode right ? Or are you able to keep swinging away once you have made the mode change, if a re BG has to be made every time you change modes would this not take a good length of time for the ground data to be back up to speed ?

Marty

Again, the name almost gets in the way. When fine gold was first released on the 5000, people thought it a mode only for tiny gold and poorly on larger bits, yet in the right kinds of soil it does quite well even on larger pieces. My experience with high-yield is that it only does slightly worse than general on biggest nuggets (larger than 50 grams according to the manual) but much better on smaller stuff which is a lot of what has been missed within existing patches. General is optimized for 5 to 50 gram nuggets. My experience with the deep mode is that it does better on really big pieces but notably worse on small to medium sized nuggets. I would only use deep as a final patch cleaner after I thought all the small stuff and trash were removed this spot is a location where I believe there might be deep multi-ounce nuggets - the user manual bears this out by suggesting that this setting is “not for general use”. When Steve Herschbach and I were first using the GPZ prototype, we were hunting in general mode with the same thoughts in mind as you have expressed. The minelab folks were asking us why we didn't hunt in the high-yield where we could and after further experience that is what we are both using now: high-yield wherever we can get away with it (and normal whenever we can get away with it, difficult when we cannot). High-yield is not a mode that does great on tiny gold and terrible on everything else. I think it gives up only a little on nuggets over 10 grams to the general mode.

I think because of the timing of extra deep it may help on moderately salty soils that are dampened, but I am not sure to what degree it might be better than the 5000, as a lot depends on the settings used especially with the 5000 in its salt mode. There are a lot of variables. To be honest, although we do have some salt areas here, I have only a limited amount of time in prospecting them with the GPZ. They are not nearly as common here as they are in WA.

Your posts make a lot of sense Chris

On some of the more moderate to severe ground, here in the triangle for instance, I'm often stunned by the following from those
I now call the hairy chest brigade, you must swing a mono Coil on a GPX series at all costs.
mono being flavor of the month.
Even though on a lot of this ground a mono coil has no business being there.
Yes you can operate a 16 – 18 inch mono but at what cost?
Enhance or Sens Smooth only
Now switch to a 16 – 18 inch DD where you can run in Normal – Fine for instance pulling decent gold at greater depth right out of the mono operators scrapings.

Sorry Chris but I differ to disagree I have found in the ground I detect that General mode run rings around high Yield for target response. To get the same response in high Yield you have to increase your sensitivity to 16 or 18 whilst in General mode 10-12 sensitivity. That's why we detect mainly in General mode and ground type mainly Difficult or normal when we can. Less hot rock country.