This guy uses a Minelab GPX 5000 to hit the deep ones

A very clever way to find deeper targets. I think this procedure would only work in certain areas, but these videos will show you that deeper is better.

[metaldetectingforum.com]

All seven videos combined was like 12 minutes. It is fun to see people be creative.



Edited 1 time(s). Last edit at 08/11/2013 12:38PM by goodmore.

Mike performed a valid head-to-head test. A lot of labor. A lot of education. A lot of reward. (Man after my heart). Akin to my "Love is Deep" article (also performed with a Minelab pulse induction).

And still............. most folks do not believe that targets are deep.

You must have deep pockets and patience of a saint to execute this approach. I would have liked to have seen an F75 LTD running in all metal CL mode or a Tom-tuned CZ-3D over those same targets. Excellent vids nevertheless...

The sunray probe really helps with target ID too. Gives you an idea if its iron or something non iron.

go-reb - I believe he mentioned at one point he couldn't use a F75 there due to high EMI.



Edited 1 time(s). Last edit at 08/11/2013 03:48PM by Gary in Daytona.

now this is deep!

[www.dailymotion.com]

Keith



Edited 1 time(s). Last edit at 08/11/2013 08:46PM by Keith Southern.

Keith Southern Wrote:
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> now this is deep!
>
> [www.dailymotion.com]
> x5000-metal-dedektorleri-define-dedektoru-www-dede
> ktorcu-com_tech
>
> Keith


I have watched that video several times. It is just incredible. There IS layers of old goodies beyond what our VLFs are detecting.

Running "CL" in low sensitivities negates some/much of the EMI susceptibility of the F75. It would have been interesting to me.

Keith Southern Wrote:
-------------------------------------------------------
> now this is deep!
>
> [www.dailymotion.com]
> x5000-metal-dedektorleri-define-dedektoru-www-dede
> ktorcu-com_tech
>
> Keith

Cool video and amazing depth on small coins

but I don't see myself running out to spend 5k on one just to use on maybe 1 or 2 sites per yr if lucky!

If I could use it on a daily basis at 90% of the sites most of us hunt here in the states = "maybe"!

I guess if you live out west where you can find gold it might be worth it and then use it for locating coins/relics now and then too on the right site/s...

I never really checked into one of these detectors because I can't afford one and really don't want one. But they use the term discrimination. Do these PI detectors have discrimination or is it more or less what the TDI offers?



Edited 1 time(s). Last edit at 08/13/2013 12:12AM by goodmore.

goodmore Wrote:
-------------------------------------------------------
> I never really checked into one of these detectors
> because I can't afford one and really don't want
> one. But they use the term discrimination. Do
> these PI detectors have discrimination or is it
> more or less what the TDI offers?


No...the GPX machines are unique in that they can "discriminate" iron to a small degree. But not like a VLF machine can. The GPX machines will give a broken tone over iron down to a certain depth...but it is light years ahead of what any other PI machine can do in that regard. The depth it can "discriminate" down to, is about 12 inches. That is all well a good...but you're talking about a machine that is capable of detecting down to 20+ inches on coin size objects in the right hands...and down to 15-18 inches in the hands of an absolute amateur with it. So in other words...once you get past the 12 inch mark on iron, it starts to sound less broken up. The trick to it, is to go ahead and start digging...and if you get the coil closer to the target and it starts to break up, it's pretty much guaranteed to be iron. If you get closer to it and the signal gets even smoother...it's not iron at all.

The TDI doesn't really discriminate. Someone else can explain it better than I can...but it's more of using the ground balance of the machine to give the illusion of discriminating. It changes the audio channel (low conductor/high conductor) in that you just don't hear the signal...even though it's really still there. There is a trick of offsetting the ground balance and putting the machine in HIGH conductive mode only...in which you CAN pretty much eliminate a nail from sounding off as a high conductor...BUT doing so really kills the depth of the machine by quite a bit.

The good news about the GPX machines is that for coin/relic hunters, there is no need in having the GPX 5000. The timings in the machines from the GPX 4000 - 5000 are pretty much the same as far as the ones you would want to use for coin/relic hunting. The GPX 4000 and 4500 would blow you away and, is currently what I am pursuing as a used machine. In the used realm, you can find them for under $3,000 with several accessory coils, etc....AND as I said, they would be identical as the new 4800s and 5000s with the timings you would be using.

As I understand, it is possible to use any PI machine instead of those GPX5000. Going to try my Whites Surf PI within E-Trac in a park after some rains.

Thank You Daniel. You saved me hours of research time. Maybe some day we will see a waterproof PI with discrimination for beach hunting. That would be something I would be interested in.

If you want a Minelab PI machine, just hop on a plane to Dubai. ML's official mideast/africa distributor is practically giving them away. These are the genuine article - not Chicom knockoffs.

GPX 5000 -$2500

GPX 4500 - $2200

Notice how all the other detectors are for sale at "normal" prices. Minelab must have a boatload of GPX'S to unload.

[www.depardetector.com]

Rick Kempf
Gold Canyon AZ- where there is no gold

No need to hop on the plane. Those are the prices here in the US too. Some can be had cheaper if you are really interested in buying and find the right dealer.

Wow - you are, of course correct - I had no idea that the market had collapsed so completely. I had heard from other sources that sales of detectors in Africa had dried up - they must have a few shipping containers of these things sitting around!

Rick Kempf
Gold Canyon AZ- where there is no gold

Got me one,,love it. A 4500 that is.

Looks like a great way to dig a lot of nails

I have one particular park I would love to try using a GPX at but I don't have one.
The old coins start at 7". Everything above that is clad.. It has below average trash targets for a park but it's hard to crank the power
because of the ground conditions. My CTX recommended sensitivity runs in the single digits most of the time.
I try running it above 20 in manual but its real noisey.
I have had some luck the last couple times I was there running my detector in Pinpoint Mode.
It's not easy and I can only do it for a short time before I get burned out but I have had some success.
I have found a gold ring, silver bracelet, Barber Quarter and a few Mercury dimes with this method.
I just look for deep targets that have a nice coin size sound to them in two directions and check them in the normal detecting mode.
Numbers are unless so I just go by tones.
Anything that is below 7" and gives any hint of a mid, high or no tone at all gets dug.
Most nails will sound off as iron but the little short ones and the ones facing straight down will fool you so you will dig some.
I wish the CTX had a true all metal mode besides the pinpoint because it is difficult getting it working right. Sometimes the ground just makes sound
whenever you move the coil so you have to constantly restart the pinpoint.

Cabin Fever Wrote:
-------------------------------------------------------
> I wish the CTX had a true all metal mode besides
> the pinpoint because it is difficult getting it
> working right. Sometimes the ground just makes
> sound whenever you move the coil so you have to
> constantly restart the pinpoint.

Cabin Fever,
Excellent technique. I use it constantly. (Here lately, my old ones are all starting at 8"...in mineralized ground.)

Yes, that pinpoint tone shift is annoying/troublesome, and exacerbated by even mild mineralization.

One thing you can do to help eliminate the pinpoint threshold shift, is to turn on GB and carefully/precisely ground balance.

That will eliminate the ground/tone shift when you lock pinpoint.

You've got to be precise when balancing, though, as if you're off (even a little) it will adversely affect depth.

I check to see I've got it right (after balancing), by first locking pinpoint on the (clean) ground and listening for a change while I raise the coil...
...then quick off/on while holding the coil a foot or two off the ground, and listening while I lower the coil.

If there's a tone change, re-do the balance until there's not.

You know you've got it right when you can hear multiple faint signals every pass of the coil.

(One other interesting thing to note, is that even if you turn GB back off, the threshold shift effect still won't be as bad as it was before you GB'd.)

mike



Edited 1 time(s). Last edit at 06/22/2016 10:05PM by Mike in CO.

Thanks for the tip Mike!
I will try that next time I'm at that park. I couldn't really figure out why sometimes the CTX wouldn't cooperate while hunting in pinpoint.
When it's working right it's very powerful and fun.