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GPS Mapping with the Minelab CTX and GPZ Detectors (Part 1)

July 29, 2016 11:04am

Steve Herschbach

Welcome to part one of a multi-part series on using the GPS system that comes with the Minelab CTX 3030 and GPZ 7000 metal detectors. I own both these detectors and have found that the built-in GPS capability these detectors feature along with the XChange 2 software is an invaluable tool. Unfortunately, it is also a much underutilized tool, with many owners of these detectors never using it at all.

Let’s tackle one question upfront that concerns many people. What about the security of your data – the locations where you have found valuable items? Rest assured that under normal circumstances neither Minelab nor anyone else, can see or access your data. It is not stored in the cloud or anywhere else except on your metal detector or your PC once you transfer the data.

A GPS is a passive receiver device and while in use, no data is transmitted from your detector to anywhere. In fact, the GPS system will not store anything permanently unless you specifically direct that it do so. Even if you activate the GPS system, all tracks and positions are lost forever when you turn the detector off, unless you specify otherwise. This means, that you can use the GPS built into your CTX or GPZ to track your starting position and where you have been for, as long as the detector is powered on, knowing that everything will clear as soon as you turn the detector off. This alone can be a valuable tool, though by opting not to store the information, you are losing information that could be valuable in the future.If you do save the information on your detector, it can be transferred to a PC for viewing in the XChange 2 software. The data stays on your PC and is not transmitted anywhere. You can save tracks and location information to your PC and then reload it to your detector at a later date. None of this requires connecting your computer to the internet and as long as you do not do that, it is impossible for your data to be accessed except by a person with direct physical access to your detector or your PC.

Below is a block diagram showing how Minelab integrates GPS with their detectors. They call it GPSi technology, something other major detector manufacturers haven’t yet implemented.

GPSi diagram

GPSi uses the high performance and flexibility of a u-blox GPS positioning engine to seamlessly integrate location and time data with detector settings and target information. This creates WayPoint, FindPoint and GeoHunt files that are compatible with XChange 2.

XChange 2 does offer the ability to download Google Earth maps and overlay your saved tracks and locations onto those maps. None of your location data goes to Google to allow this to happen – it stays on your PC at all times. However, to download and use the Google mapping information, you do have to create an account and log in to download the map files.


There are two risks to be aware of. If you have data stored on your detector and the detector is borrowed or stolen, the person in possession of the detector could access the data. Second, any computer that is connected to the internet is at risk of being hacked. That same level of risk exists for all data on your computer. Your only concern about your mapping data should be directly related to any concerns you have about your detector being stolen or your computer being hacked. Other than that, there is nothing built into the system or software that can compromise your data.

I hate to spend so much of this article on security but it is a serious concern for some prospectors with the GPZ especially. I suspect it is a major reason why some people refuse to even consider using the system at all. I don’t suppose I will convince everyone otherwise. However, if you use your computer for online banking or storing personal information, then you have already made the decision that your computer is halfway secure. The chances of you being specifically targeted by hackers for information sources as obscure and as rare as the Minelab XChange 2 software is as close to zero as it can get.

Why might a person want to use the Minelab GPS mapping system in the first place? The main reason for me is that it has helped me to take a longer term and more methodical approach to my detecting. I admit I like to wander around aimlessly while metal detecting, just following my nose where it leads. The problem with that is I can wander aimlessly around an area for years, yet never feel like I have thoroughly detected it.  In the long run it is a very inefficient way to operate, with a high likelihood that the same ground will see the coil time and again. Having a plan to work areas in a systematic fashion insures not only against items being missed but that time is not wasted detecting the same ground more than once.

The larger the area you want to work, and the longer the time frame over which you may be working the area, the more advantage you will see in tracking and mapping where you have been. Examples are people hunting huge plowed farm areas looking for coins and relics. Prospectors tend to live by maps and remote locations, sometimes with years passing between visits. Even hunting a large park or a large beach can benefit from mapping hunted areas over time to know what has been hunted and what is left to hunt. It is the best way you have available to be sure areas are not overlooked as time goes by.The second benefit that can be realized is in recording and mapping find locations. Patterns develop over time that can be extremely valuable to you. That huge featureless farm field may eventually show clusters of finds that point to old habitations or roads and trails. Prospectors can use accumulated nugget locations to develop theories about the direction in which the gold is running, leading to more finds.

Hopefully this first entry has helped possibly alleviate some security concerns you may have and piqued your interest enough to check out the rest of the series. In the remaining entries I want to give specific examples of how the system works and more details on how to use it to improve your detecting success.


Stay tuned!

For more information about XChange 2 click here.

To view the XChange 2 User Manual click here.



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Interesting article Steve. I couldn't agree more as to how useful using GPS Mapping and Exchange2 is as to improving finds. I touched on some of this in my first article back in 2014 about finding patterns from detecting areas over time.

Looking forward to your next article.


Posted By: MarkGerlach on July 29, 2016 10:35pm
Thank you Steve, part one and two read and passed on to our followers, thank you, Russ, Lunatek
Posted By: RussKirk on October 18, 2016 12:20am