GPX Help For A Beginner Please?

[Rege-PA]

Please help me out with some GPX experiences. Living in the eastern US I don`t have the opportunity to use the 5000 much. I try to do two or three trips a year in gold country, so my actual time on the machine is limited compared to those who can get out more often, so any advice or helpful hints are much appreciated to shorten the learning curve.

[Steve Herschbach]

This is as simple a basic guide as I can imagine, and simple is often best. You can get a GPX real screwed up fiddling with the settings! So the most important tip of all is The Factory Reset.

OK, you have a fresh start. The GPX will save your changes going forward when you turn the detector off. If you get worried or confused, just do the Factory Reset again.

I think there are three very basic Soil settings (or Timings as Minelab calls them) on the GPX 5000 for beginners, all which use the stock 11" mono coil. The GPX series was designed with mono coils in mind so just start there. The three Timings are Normal, Fine Gold, and Sensitive Extra.

Normal is the "go to" mode for the beginner. Set all the switches on the front control panel as follows:

A. Turn the detector on by pressing and releasing the power switch on the rear control panel, the same one used to do the Factory Reset above. B. Raise the coil off the ground and press the Auto Tune button to reduce electrical interference. The tuning process takes approximately 60 seconds. Do not move the coil or pass metal objects near the coil until you hear 3 beeps. C. Turn the Threshold control clockwise until a hum is audible through the headphones. D. Press and hold the green Quick-Track button on the end of the foam covered handle. While holding the button depressed, raise and lower the coil, between 1" and 4" (25mm and 100mm) from the ground. You may or may not hear variations in the Threshold sound while doing this. Any variations in the Threshold will smooth out within 3–5 seconds. Release the Quick-Track button. You have just ground balanced the detector. E. Again adjust the Threshold to a very faint but still audible level. It should be smooth with only minor fluctuations.

You are now ready to go find gold! There really is only one other key adjustment the beginner needs to know at this time. On the rear control panel turn the Function Select knob until the RX Gain setting is highlighted.

The default setting is 11. If the detector is operated a short while and everything seems very stable, try adjusting this setting up a couple notches. If you change the RX Gain, it is a good idea to do the ground balance procedure above again after making the adjustment. Turning the Setting knob adjusts the RX Gain up and down. This is the basic sensitivity setting for the detector. Higher settings give you more depth, but also make the detector more susceptible to electrical interference and ground noise. The goal is to find a higher setting that does not make the detector threshold too unstable. You want a smooth threshold or as near to it as possible. On the other hand, if the default setting of 11 seems too unstable, reducing the RX Gain will help. Settings of 14 or 16 are not unusual, nor are settings as low as 8 or 9.

The real secret to nugget detecting is coil control. Sweep over the ground while either scraping the ground with the coil or keeping it 1mm off the ground. I see people obsess over getting the best detector setting, then give it all up and more waving the coil an inch or two or three over the ground! Careful methodical hunting and attention to faint signals is the best way to learn.

There are two alternate Timings I want the beginner to know. Fine Gold and Sensitive Extra. Think of Normal as just that - Normal Mineralization. Fine Gold is a bad name for a setting that is better thought of as Difficult Mineralization. Sensitive Extra should be thought of as Low Mineralization. If the GPX does not want to run smoothly in the Normal Timing and is having problems with ground noise or hot rocks, even if you lower the RX gain a bit, flip the Soil/Timings switch to Special.

The Special Timings are selected via the LCD menu but the default is factory set for the Fine Gold timing. Simply flipping the Soil/Timing switch to Special puts you in Fine Gold. If you have been messing with the RX Gain while in Normal you may want to go back to 11 or 12 at this point, and again do the ground balance procedure as described above. Fine Gold, despite the name, was designed specifically for bad ground and eliminates all but the worst hot rocks. It is the preferred setting for bad ground. It runs so well people get in the habit of using it all the time. Do not do this, it does miss gold that can be found in the other two Timings discussed here. The key always with the GPX however is to seek quiet, stable operation, and Fine Gold does this very well. Again, experiment to find the highest RX Gain setting that you can run while maintaining stable operation.

If in the United States in particular you may run into areas where the mineralization is low. You will know because you will be able to run in Normal with the Gain set very high, like 17 or above. If so, give Sensitive Extra a try. This is a very powerful and sensitive setting, and actually is the hottest setting for small gold nuggets, not Fine Gold as the name suggests. To try Sensitive Extra, again you need to switch from Normal to Special with the Soil/Timings switch. But now you need to use the LCD menu Function Select to find the SPECIAL settings. This determines what happens when you set the Special switch. Adjust the setting from the factory preset (FP) of FINE GOLD to SENS EXTRA.

The Special switch now means Sensitive Extra. You can flip to Normal, and if you go back to Special you will be in Sensitive Extra. This will happen until you use the LCD menu to change the SPECIAL setting back to FINE GOLD or a different alternate timing. You are programming the Special switch setting to be whatever you want. The best thing at some point is to have Normal set up with either Fine Gold or Sensitive Extra as a preferred alternative, depending on the ground types you encounter most. Remember that if you ever do a Factory Reset that Fine Gold will become the default setting for the Special switch.

Now that you are in Sensitive Extra, you probably need to go back to the RX Gain setting default of 11 again to start, and ground balance again. Seeing the pattern here, change timings or gain, you should ground balance again. Here is more detail on the ground balance procedure and how to check it periodically. Maintaining proper ground balance is critical.

If going to Sensitive Extra starts causing problems with hot rocks or ground noise, just go back to Normal.

OK, to sum up. Normal for Normal ground conditions. Normal is the key and your reference point. If Normal is having problems, then use Fine Gold for bad ground and hot rocks. If Normal is working almost too well, try Sensitive Extra for mild ground/minimal hot rocks. In each Timing find the highest RX Gain that will allow stable operation. Check your ground balance often and do again whenever in doubt. Go slow and carefully, and when learning investigate all targets. If you are digging ground signals or hot rocks, use lower gain levels or change Timings.

That should cover most beginners and even a lot of regular users just fine. If you hunt the same areas regularly you will figure out what works there and rarely need to change settings. The GPX is actually pretty forgiving compared to a hot VLF detector. This is of course only my suggestions, not set in stone, and maybe not as clear as I hope it is. If it is not clear enough please tell me or offer suggestions, but my goal is to make it simpler, not more complicated, if that is at all possible.

For additional details and information see the GPX 5000 Owners Guide and the detailed timings charts on this website.

 

[Gold Hound]

Hi Steve

I think you did a pretty good job on your guide for beginners as the GPX can be a rabbit hole for the casual user.

My first advice is always;

READ THE MANUAL, then read it again, then read it some more! seriously you cannot read the manual enough!

[Steve Herschbach]

Thanks Gold Hound, any suggestions appreciated. The problem is there is always more to talk about with the GPX. Just trying to explain that the Special Switch is really just selecting something else set somewhere else gets confusing. The big fail on the GPX was in not allowing the custom modes to be fully custom. You can only save some settings and not others so most people ignored them. If I could have had just one simple change though it would be to swap the threshold setting from the knob into the menu and put the RX Gain on the knob. I almost never messed with my threshold setting but was always wanting to tweak the gain.

I once talked to the engineers and suggested they develop a system of "automatic timings". The GPX knows enough to sense and adjust the ground balance. So it knows when the ground is bad. Why not just suggest to the operator based on what it is seeing what timing to use, or even have that adjust automatically on the fly? He thought it a great concept, but I think even then the GPZ was already on the drawing board so it went nowhere.

[Gold Hound]

I like the Auto timing Idea a lot Steve.

I recon they could expand on your Idea and have a mineralization line graph on the screen telling us what the current and past ground conditions are doing under the coil and the suggested timing.

You could use this to identify and follow a particular ground anomaly.

And wouldn't it be cool if they had a visual threshold display that acts like an oscilloscope and visually shows you the threshold and target response!

They could easily with some work incorporate these in to the next generation ZVT detector!

Just imagine how this would open up the gold fields again!

[klunker]

 Rege-PA;

There is no other detecting forum that I have seen that would give you that much excellent information in such an understandable way.

I would like to add that when you get comfortable with what the settings do, then Fiddle with it, especially over a likely gold target.

  Our thanks again to Steve.

 I would like to cross breed a 5000 with a Z- but it would probably be sterile.

[Rege-PA]

I agree, alot to digest, just got to wait for some warmer weather and start experimenting.

As to your idea about cross breeding, I think it would be a good idea, I don`t care if it can`t have kids but it better find nuggets!

[Rege-PA]

Hi JW,

Good to hear from you and hope you are on the gold.  I`m savoring each bit of info and appreciate all the advice, at some point in time I have to man up and get this show on the road, just have to learn the basics then move to the finer points. I do have good technique, learned from one of the best in WA in 2012, because of my injuries low and slow is my only way, so I am blessed in that respect. I am thinking heavily of a test garden using mineralized soil to a depth of a meter, that way I could experiment with settings and coils. Do you know of any way I could get an average of WA or mineralized ground in your area? I can get some pretty mean ground from Virginia and adding black sand should give me the mineralization I need, but don`t know what iron/ground number to use. I do have an MXT that would give me a reading in the prospect mode.

Any thoughts appreciated.

[Matette]

Hi all, I too would love some advice, have owned my GPX 5000 for 18 months, in that time have only ever founds dozens of bullets, bottle tops, fine wire, nails, lead slugs smaller than match heads; you name it I've dug it up, including a cast iron wheel off a mine trolley? When I purchased off the Minelab outlet here in bendigo, they suggested putting a nugget finder coil on instead of the factory coil, however after 18 months I still love getting out there but I'm starting to think something isn't right and it all points to me? Please assist? Mathew

[Steve Herschbach]

Hello Mathew,

Welcome to the forum!

Sounds like as far as the detector goes you have it figured out. It is simply a metal detector and you have it detecting metal. Bullets and lead are the best indicator of your detecting skill. The smaller the bullets you find and the deeper they are, then the better you are doing. Lead and gold read approximately the same.

Now you just need to put the detector coil over some gold. Buying a detector is easy, getting it to work is actually pretty easy. Getting the coil over detectable gold - not so easy. Like buying real estate it is all about location, and that knowledge is gained through research. The easiest solution for beginners is to go where gold has already been found. Most any decent gold location will usually give up at least one more gold nugget if hunted patiently. In order to do more than find just a few nuggets you have to get off the beaten path and explore hard to reach locations. This involves more research and a willingness to take risks in the form of time spent detecting places where good has not been found before by many others. Learning as much about gold geology as possible, including reading geologic maps, is very key to success.

Bottom line? Metal detecting is easy. Prospecting is not. Most people can become reasonably good with a detector. Becoming a good prospector is a totally different thing in that what you are learning is where and how to place yourself over shallow detectable gold. In the U.S. I usually recommend joining a club to meet others whole may be able to act as guides and mentors. I am not sure if the equivalent resource exists in Australia?

Gold Fossicking Australia http://www.gold-net.com.au/fossicking1.html

Gold Prospecting U.S. http://geology.com/articles/gold-prospecting-tools/

Patch Hunting http://www.minelab.com/emea/treasure-talk/so-you-want-to-find-a-patch