XP GOLD MAXX POWER (GMP) - Field Test

Well Ozzie between the 9 inch ctock coil and the 5 inch NEL I see not much difference in unmasking as long as it just nails between the two...

Now if the site is of the type that is mixed with larger iron the advantage goes with the 5 inch ...

Being without a meter and if you cant dig it all the GMP in a more modern trash site is going to require all targets dug unless you just dig the highest tone .. but then the magic is gone and might as well use something else...

The GMP is a site machine ...

Modern trash areas mixed with older goodies I would lean towards a T2/f75 G2/GBPro or AT series if relics are what your after...or even a DEUS somewhat...yet the DEUS is still more geared for site work even though it has a meter its going to dig alot of trash that reads good....

My favorite machine for multi period sites is the CTX...yet the dirt needs to be packed not flipped over the years...

The closest machine I have seen for the money in GOOD I.D. in multi layer multi period sites is an AT-PRO Garrett did an excellent job on the I.D. accuracy of the machine especially when co-located....If you dont have a CTX the AT-PRO is awesome.. and 1/3rd of the price..

I try to stay out of multi period sites with modern trash though...I like iron to be my trash problem...

Keith



Edited 1 time(s). Last edit at 02/03/2014 04:14AM by Keith Southern.

Quote from Keith; I try to stay out of multi period sites with modern trash though...I like iron to be my trash problem...

I hear ya Keith. Around here, many of the old stone homes are still inhabited. The woodwork and siding has been capped with aluminium. The little bits and drops from trimming this aluminium are all over the place along with roofing nails. The iron lath nails and framing nails are deeper from renovations past. It's a masking nightmare. Reading your info and sorting out your knowledge, I've come to the conclusion that I have the best tool for the sights in my neck of the woods....the f-75ltd with the 5" and the 11" coils.........the cz for the fields away from the homes.

Still wouldn't mind owning a GMP though....I believe we'd get along just fine.

Well I managed to get a GMP and now must start the learning curve, plenty of advice on here but keep it coming.
Thanks to all.

Does XP not make the Goldmaxx Pro anymore ? .....Jim

Keith sent me his 5" NEL coil for the GMP. I have been testing it extensively. So far........... in a nutshell:

Very solid/well built coil.

In real-world dirt (Florida) conditions, I am finding that it will detect penny/dime sized targets to nearly 5"......real-time. This is about an inch deeper than the small factory elliptical DD coil. I have good reason to believe this is due to a not-so-tight electromagnetic footprint. Not as tight/narrow as the small factory elliptical DD coil. So.......... the trade-off is............ it'll go a bit deeper at the cost of a bit of adjacent target separation performance/ability....... as compared to the small factory elliptical DD coil.
In an air-test........ this NEL coil detects to much greater ranges.

What my (near) final conclusion is: This NEL 5" coil views the world differently..... with approx 17% differential....... over the small factory elliptical DD coil. In the right application............ 17% is a useable/measurable/applicable amount of difference. Said differently: This coil will 'see/detect' 17% more targets that the small factory elliptical DD coil will never see. But........... you must understand........ the reciprocal also holds true. There are 17% of targets that this NEL coil will not see........ and only the small factory elliptical DD coil will see. This is due to the wider electromagnetic footprint of the NEL coil.

It's a true eye-opener when you have 3 different coils. They are 3 different sizes. They produce 3 different electromagnetic footprints. And you learn/experience/witness: there are quite a few targets that only one of the coils will detect. Then...... there is a different group of targets that only another coil will detect. Same holds true for the last of the 3 coils.
This also holds true for/from detector-to-detector.

Keith........... I only have a few more specific/discrete tests to perform with this coil.
((( In this sand-bar high sink-rate State of Florida........ it is difficult to find application for a coil that has a real-world usable depth of 5" on coin-sized targets. When you do find application..........and I can/do........... it's a critical tool. )))

I dont see the footprint as tight as the 5 inch FT coil for the G2 Tom...

as far as the airtest and inground...I see the best results with that small coil Vs the XP 5x10 around here wiht the ability ot see through pinestraw...the 5x10 would not see through pinestraw and report target's....

the good airtest depth seem to have the advanatge of airgap punch..I find it more usable in my wooded sites than the XP 5x10 for this purpose when I want to see what the 9 inch cant see on certain size iron from masking....

Bur yes I can tell on the 5 inch models (I have 2 now).. that they are not as Tight of coil's as could be...The Xps electronics can handle a wide coil..the G2 needs a tight coil!

I want to try the NEL 5.5x9.5 against the FT 5x10 but as tight as the 5x10 FT coil is( tightest coil I've used to date) theres no way the NEL 5.5x9.5 can get tighter I feel...

I do like having the option to get hold of aftermaket specialty size coils...But I feel FT has a one leg up on their coil design's...but they should they built them for their machine's..

I see the NELS if used..... to be used on machines that lack THAT SIZE COIL and you NEED that coil for a certian requirement..

I see it as useful on the GMP for a small coil since there is non....But on the FT machines I think maybe the larger than stock NELS may play into the scenario for depth addition to the machine's if that the route one wants to take.. ...

take your time with it ..Im in no hurry...

thanks for using it and reporting on it.


Keith

Good report Tom!

Recently picked up the GMP, What little time I have on it so far very impressive machine.

Have the Vista Gold to compare the two, See some advantages with both but looks like these two will be my serious relic hunters.

One feature I like on the GMP is the three tone feature for gold jewelry hunting, The middle tone accepts the bulk of dropped gold jewelry finds so it's going to be interesting to see how it does strictly as a gold jewelry hunter going after middle tone signals. This is an area the Vista Gold falls short being a 2-tone machine the second tone was for everything above iron, Glad to see the GMP has both the option of 2 or 3-tone.

One thing, Have read some users mentioning the GMP feels sloppy and loose, It does have that sloppy loose feeling but this problem mainly comes from the large arm-cup. After adding on an arm-strap this took away that sloppy shaft feeling now it swings tight, I think this is were most of the sloppy issues arise the arm-cup is too wide.

Another neat thing is in comparison to a TR mine/prospecting detector it is smaller when collapsed, Really like this for back pack storage especially when using a bicycle to get to an old site.



Lot's to learn with the GMP, very impressive so far!

Paul (Ca)



Edited 3 time(s). Last edit at 02/10/2014 04:45PM by Old California.

Well worth re-mention: I keep having repeat experience(s) whereby the F75 LTD/SE (in boost process mode) with the 5" DD coil installed......... is having nearly parallel performance to the XP GMP with it's stock 9" DD coil installed. In some cases.... the 5" F75 LTD/SE is proving to be slightly deeper than the 9" GMP. Adjacent target separation is where the 'eye-opener' comes into the equation. With this large dramatic/differential/delta/difference between the 5" Fisher.... vs .... the 9" GMP .................... they both have "similar" adjacent target separation characteristics......... especially in carpets of nails. Major accolades goes to the large 9" coil on the GMP for adjacent target separation abilities. Major accolades goes to the small 5" coil on the F75 for exceptional/comparable depth performance in the same trashy environments. If only to combine the two accolades.

With the NEL 5" DD coil installed on the GMP...... a different world is opened. The adjacent target separation characteristics are far above the performance of (same physical dimension/size) 5" DD coil on the F75; yet, the 5" GMP's depth capabilities severely lack. (((Robbing Peter to pay Paul))). This commands/necessitates: Using the right tool....for the right job.

In any of the above cases, there are groups of targets whereby only ONE of the combination/configuration will detect that specific group of targets. Switching to a different group of targets......... and yet, only one DIFFERENT configuration/combination will detect this different group of targets.

Because this post is also heavily about the GMP............ if someone feels it could/should also be posted on the XP GMP Field Test thread......... you are encouraged to (cut-n-paste) do this!

Tom
Reply Quote Report

Sorry NasaTom,......I did it again. I will post the link to my thread to this thread. My apologies:
Link to my thread: [www.dankowskidetectors.com]

((( Not a problem )))

Sounds like I'm going to be holding on to my 75 SE for quite awhile yet. It's going to be interesting to using it with the GMP on the same sites.

Aaron

The rain and sleet were heading toward Tennessee this afternoon. My second cousin and my aunt were here sitting with my mother. I saw the opportunity and, at 4 pm (about an hour left of good light) I headed toward the site that I am presently pounding. I went over the spot where I found the 14K gold ring with my Deus (my ex-Deus). I got a signal on the GMP w/9inch coil. It was a buffalo nickle!!!! About three minutes after I geared up and started scanning. I have found ALOT of finds in the first 15 minutes of my digging!!! With several different detectors. I am starting to discern a pattern. My head and ears are fresh and can pick out those mid or hi tones easier. Maybe that's it. Maybe not. I am going start using little wire blue flags from ACE Hardware and gridding this place off. I am going to dig every mid or hi tone. When I leave, this place can be called.............pounded!!!!!! GMP-style. (I hope to try it, when the weather breaks, with the 5 inch NEL coil). Alot of the iron in the ground is bigger. Not only nails. But pieces of a coal burning stove......etc etc. Anyway........keep on saving that history!!!!! In SPITE of archeologists. I wish that they would befriend us and not look at us as hobbyists with a profit motive. But that is for another thread on another day. Happy Hunting to all!!!!

Nice going Kevin!
We had another snow storm up here again, it will be awhile till I can hope to start using my GMP however I look forward to comparing notes with you.

Aaron

Kevin, use coloured plastic tent pegs and not wire flags, then you can detect right up to them.

Or some plastic poker chips......

Aaron

Good idea guys. Thanks for the tips!!!!!!! I never even thought of the little wire on the wire flags!!! I would have likely had holes dug around all of the flags!!!!! Seriously. I'm THAT challenged!!! lol Seriously, I appreciate the heads up and the good ideas. Can't wiat for the sleet and frozen rain to mealt and the weekend temps to climb to 50's or even 60's. I installed the 5" NEL coil on the GMP for my next round. There is a small spot that has been productive but has old iron of varying sizes. Chunks of an old stove. Nails. Horseshoes. Etc etc etc. May I can pul out something decent. I have only found one piece of silver here. I find that amzingly hard to believe. Several Indian Heads and wheaties. One buffalo nickle. One roosevelt silver dime. This would have considered a nicer home back in 1905 when it was built. By a physican. With children. Has an old gazbo and an old well house. Perfect locale. PLUS, there was an old home site here BEFORE the house that was built on 1905. Several layers of time. I need a dozer to peel off about 4 inches of sod for me. Pile it up....and I'll go through it with a magnet. I believe that there is alot of stuff masked.....down under. Gotta get to it

As I progress through 4 decades of detecting, analyzing "need's" .... vs .... technological advancements............ and collectively combine this data with forum members provided data on this forum.......... a clear picture becomes resolut. . . . . as to future direction.

Keith Southern has generously given me a 5" NEL coil for the XP GMP to keep. Whilst hunting with this coil.... I ask questions like:

1. What am I trying to achieve?
2. What am I trying to 'discover'?
3. What would be my 'dream' resultant?
4. Why am I doing this?
5. Is this detector (with current configuration) no longer a 'general purpose' detector; rather a specific/specialty detector?

Every time I hunt with a small coil, I get a gut-wrenching/sick subconscious feeling of: strongly unwanted "depth handicap". I can not over-emphasize the extreme potential of near-fatal end-resultant ..... due to this 'reduction in depth' that ensues with utilization of smaller coils. Yet....... there are many areas that can never be detected with standard sized coils....... due to high volumes of trash/targets.
Large coils........ in 'some' cases,,,, will provide some greater depth that we are looking for; yet, once again, can ONLY be used in areas whereby targets are sparse..... where minimal human activity prevailed (not necessarily a 'wanted' / ideal hunting scenario).

So, what is it..... that we need. . . . . that is within the realm of do'able/achievable current technological capabilities/advancement.

Stated Problem: The deeper a detector can 'see'......... the more targets it will 'see'.

Reducing the size of the coil..... and tightening up the electromagnetic footprint; subsequently (through laws of physics) reduces depth performance. The deeper you can see....... the smaller you will want the size of the coil (and subsequent size of the electromagnetic footprint)...... so as to circumvent masking and adjacent target separation failure.

Stated Answer: It would be nearly ideal...... to have a detector that has a small DD coil, with all of the subsequent attributes a small coil provides; yet, achieve greater depths over current-day technology.

Whilst hunting/detecting with this 5" NEL coil equipped XP GMP.......what comes to light is: The quest would be to achieve F75 SE boost-process 11" DD coil depths....... yet with XP GMP iron partial see-through & adjacent target separation capabilities....... with mineralization/ID accuracy taken into consideration. This certainly sounds like a large request; yet, technologically, I believe we are nearly there.

((( All of the above stated....... is assuming we are still utilizing electromagnetics for detection.......... ie: no paradigm shift has taken place )))

Tom, I was hoping by the end of your post you were going to make some spectacular claim regarding how great the new "5 NEL is......

I guess that's coming ....I hope.

Aaron

No........ in fact, I have reported nearly all of my 5" NEL findings in this thread..... on this page. So far........ no additional magic 'discoveries' with this particular coil.

Opps, I forgot about it already.

The NEL 5" gos deeper but the FTP 5" is tighter, gotcha.

Can't wait for the ground to thaw so I can compare the two myself.


Aaron

No, No! I am comparing the 4-1/4" x 9-1/4" elliptical DD GMP coil to the 5" (round) DD NEL coil installed on the XP GMP.
I am not comparing the F75 LTD/SE 5" DD coil to this XP GMP 5" DD NEL coil. In this case....... the F75 SE with the FTP 5" DD coil in 'boost process' mode...... is slightly deeper than the XP GMP with 9" DD coil. . . . . in inert-to-mild dirt. (Not a typo).

Oh, ok. Gotcha.
Thx

It happened again. 85-minutes from home (one way). XP GMP. Uses/needs 8-AA batteries. I tested all batteries with a digital volt meter before departure (due to my developed/repeated battery distrust). All batteries were 1.525 VDC (+ - 0.010). About 40 minutes into the hunt..... one battery goes flat. Unit inop. Installed 8 new batteries. 4.5 hours later........... repeat occurance. One battery reversed polarity. Unit inop. Installed a 3rd set of 8-AA batteries. Completed hunt//Completed day. Good thing ... as I was nearly 3-hours (round-trip) from home...... had no more AA batteries with me. Good thing I had 24 batteries (total) with me. I do not carry a digital volt meter with me in the field........ could not test bunches of batteries...... to find out which one(s) went bad...... in the field. Upon arrival home....... I tested all batteries. Two were bad......... and the other 22 were 1.505 VDC..... or higher. It would be an easy choice/mistake to throw away the first two sets of batteries: 8 x 2 = 16........... as these two sets failed............... when.................... in actuality.............. only 1 battery (per set) failed........ and all the other 14 batteries were still new/perfect.

I am a strong proponent of 1-battery detectors. (2 is OK). One 9-Volt has plenty of amperage capacity. If it only lasts 5 hours........... that's fine.
Even though the XP GMP uses/needs a bucket of batteries......... I will still praise its iron handling accolades.

Tom:
I have had the same problems with batteries. Not with a detector but with flash units on our digital cameras. I help the wife do wedding photography on the side and I have to test all AA batteries before loading them into I the flash units. All my back up batteries are also test and taped together so no to get mixed up with the untested ones. 5 or 6 batteries will be bad in just about every 24 pack.
Corey.

Tom, Since you took the time to actually measure the voltages of each battery prior to hunting, all of your batteries tested the same due to "no-load" on any of the batteries.

A very simple way of weeding-out the bad batteries is to take 2-alligator clips, one end attached to the DVM's probes (+/-), and the other ends attached to a 100 ohm resistor.

Go back and test again (with 100 ohm resistor in parallel) and now with load on each battery, the bad batteries show themselves.


[www.youtube.com]

Actually, I have a small penlight flashlight bulb that I do this with......... if time permits!
"Voltage" is a reasonable indicator.
"Amperage" is all-telling.

Thank you NASA Tom for starting this thread. Very interesting read.

You are welcome. The intent is to help folks in their analysis and decision-making process.

Thread read.... Incredible amount of information that I have been enjoying reading-And re-reading. Incredible to say the least!

Interesting note on the Ground adjustment here...
My typical site includes the following:

Mineralized Soil. (sand/dirt combo that reacts to a magnate)
EMI-Local electric transit with overhead wires.
Lot's of corroded iron. Large and small.

Enjoying the read!!
Peter

Sounds like you have a interesting challenge...... with multiple 'conditions'.