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The GPZ 7000 has set a new benchmark for sensitivity over a very broad range of gold nuggets. However, a by-product of its exceptional sensitivity to gold nuggets is increased susceptibility to soil anomalies and unwanted interactions with the ground matrix. One such unwanted interaction is with the conductive (salt) elements of the ground.
Some soils have high amounts of alkali metal salts which make the soil conductive. Salt flats are extreme examples of this. Also, many otherwise benign soils can become conductive after a period of rain. As detectors become more sensitive to conductive targets of interest (i.e. gold), they also respond more aggressively to conductive soil.
As a detectorist, you can identify conductive soil if you know what to look and listen for. The first thing you’ll notice is that the detector will make long audible ‘groans’ as the coil is swept from side-to-side over the soil. These signals won’t be localised – they’ll be coming from large regions of low conductivity, and they’ll be deep, too. Even if you lift the coil in the air, far from the soil, at least two or three feet above the ground, you’ll still be able to hear these long audible ‘groans’.
When you encounter conductive soil, usually you’ll have to slow your sweep to tame the audible noises. With the new GPZ software upgrade we’ve provided some extra settings to help deal with problematic soils, especially conductive soil. This enables you to take the GPZ 7000 to places which were previous “off-limits” and to reduce the impact of these soils.
This second GPZ 7000 upgrade implements a new Ground Smoothing function in the Detect Plus menu. This function has three settings: Off, Locate Patch and Salty Soil.
The Off position is the original GPZ 7000 configuration you have already been using This setting is optimal for seeking targets which tend to be found deep (e.g. greater than 600mm). The trade-off with Off is that it tends to be the most sensitive to soil anomalies, so you’ll achieve the best performance if you slow your coil swing speed to deal with the unwanted ground noises.
The Locate Patch setting is a great all-rounder. This setting enables you to cover more ground faster. It smooths out unwanted ground noises, allowing you to keep a productive swing speed. With less ground noise it can also be easier to hear the fainter signals.
Mild alkali soils can still be detected in this setting.. The trade-off with Locate Patch is a slight sensitivity penalty (a few percent) for the deepest targets. However, for most targets you’ll find this setting strikes a balance between absolute detection depth and productivity.
The Salty Soil setting is a specialty setting designed to allow the GPZ 7000 to operate in extreme alkali environments that would otherwise be impossible. It is important that this setting is used only when the soil requires it, as it can have a substantial impact on detection depth. Salty Soil removes the slow audible ‘groans’ from conductive soils and retains the faster responses from gold nuggets. As a result, Salty Soil will have a bit more ‘chatter’ than the Off and Locate Patch settings; and the slow broad signals from very deep targets will be more difficult to hear.
The Ground Smoothing settings can also be changed to suit the size of coil you are using – GPZ 14 or GPZ 19:
The GPZ 14 has been designed for optimum overall sensitivity to a large range of gold nugget sizes. It’s great for deep buried large nuggets as well as shallower small nuggets. How you match the GPZ 14 with the Ground Smoothing settings depends upon how you use the GPZ 7000. If you’re after increased productivity, more ground coverage and a smoother detecting experience, the Locate Patch setting could best suit your needs. If you’re wanting to find ‘that one monster nugget’ at depth, the Off setting gives you the best chance!
The GPZ 19 offers a substantial boost in sensitivity to deep targets. The larger geometry also means that it’s more sensitive to conductive soil. The new Ground Smoothing function can used to help reduce the effect of conductive soils on the GPZ 19. However, it is important to remember that the GPZ 19 is all about depth. So, where possible, the GPZ 19 should matched with the Off setting for the greatest detection depth. However, you may find that Locate Patch gives a smoother detecting experience.
So, in summary, you now have a wider choice of coil size and ground noise filtering options to fine-tune detector performance for various conditions – from using the GPZ 14 and Salty Soil for conductive soils, through to the GPZ 19 and Ground Smoothing Off for less reactive ground and greatest depth.
This software upgrade, which also includes a Semi-Auto setting and additional language support, is available here
Further information and instructions on how to install it are available here
Read more about the GPZ 7000 and coping with difficult ground here
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I am getting gold from patches where the GPZ7000 was used before any updates, and even after the first update there was an improvement, but now it's even better.
The semi auto ground tracking GB is a real blessing, and switching between the ground smoothing modes OFF, and Locate Patch, lets me detect ground that was way to noisy before.
Only one negative, but I'm told will be fixed real soon is the incompatibility with the xchange2 software.