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Sourdough Moe

14x9 Evo On GPX - Is It Working Right?

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If you are getting 9" in the dirt on a 2.5 gram nugget with the 14x9 coil then your detector is working fine. What timing are you using?

-Don

 

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7 hours ago, Steve Herschbach said:

Completely depends on the nugget and the timings selected. Gold detectability varies a lot due to size, shape, and purity. Further, all PI timings have weak areas near the ground balance points in the timing schemes referred to as “holes”. Any nugget that’s composition puts its signal near one of these holes will have a weaker signal.

Comparing nugget signals is a waste of time. The best you can do if you think your unit is defective is compare depths with the same coil and exact same settings on a nickel with somebody else that has the same rig.

I get the idea you are new to PI and think they “go deeper” than VLF detectors. The reality is more like PI detector’s lose less depth in highly mineralized ground. In many Alaska low mineral / small gold situations there is honestly very little benefit in running a PI beyond the ability to run oversized coils. The vast majority of the gold found at the Ganes Creek pay to mine operation while it was running was found with VLFs like the MXT or X-Terra, not PI detectors.

I very much doubt there is anything wrong with the detector - GPX machines are highly reliable. Coils do have more variability though and it’s hard to rule out coil issues with any detector.

Steve your right it has to be the nugget and a low battery. I swaped out the battery and put a nickel 15 inches deep and it screams i belive i would be able to ping it 2 feet down, but i had to end the test due to permerfrost reasons

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21 hours ago, Don71 said:

If you are getting 9" in the dirt on a 2.5 gram nugget with the 14x9 coil then your detector is working fine. What timing are you using?

-Don

 

i am using sens extra

 

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On 4/16/2018 at 4:42 AM, Don71 said:

The air test is always the best case scenario for depth for all the people that think air tests are not important.

I am one of those that hold absolutely no importance on air tests at all when detecting for gold. I don't rate them out in the gold fields at all.  After all....you don't find gold nuggets floating around in the air out in the gold fields. You have to dig for them. So what is the point of air tests? Depending on their orientation in the ground you will always get a stronger deeper hit on a piece of gold that has been laying in situ for a zillion years in the ground than if you buried the same nugget at the same depth, in which case you would probably not even get a hit at all. A nugget that has been laying in the ground for a zillion years develops a "halo" effect in the ground surrounding it due to impurities leaching & "rotting" out of it over the years & being absorbed by the ground surrounding the nugget. This is caused over time by a combination of acidic agents from water, plant matter, other minerals in the ground etc that the gold is subjected to. This "halo" along with the gold nugget gives the detector a bigger target to hit on than just the gold nugget alone. Once this is dug down to & the ground "halo" broken up, the signal can be somewhat reduced if the coil is still at ground level & not down into the hole. Sometimes it can even lead to the signal being lost if it was on the fringe of detection in the first place. So that is why air tests mean absolutely nothing out in the real world of gold detecting.

Sourdoughmoe: Steve H & phoenix hit the nail on the head & I am sure they have given you your answer.

Good luck out there.

JW :smile:

  

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12 hours ago, kiwijw said:

I am one of those that hold absolutely no importance on air tests at all when detecting for gold. I don't rate them out in the gold fields at all.  After all....you don't find gold nuggets floating around in the air out in the gold fields. You have to dig for them. So what is the point of air tests? Depending on their orientation in the ground you will always get a stronger deeper hit on a piece of gold that has been laying in situ for a zillion years in the ground than if you buried the same nugget at the same depth, in which case you would probably not even get a hit at all. A nugget that has been laying in the ground for a zillion years develops a "halo" effect in the ground surrounding it due to impurities leaching & "rotting" out of it over the years & being absorbed by the ground surrounding the nugget. This is caused over time by a combination of acidic agents from water, plant matter, other minerals in the ground etc that the gold is subjected to. This "halo" along with the gold nugget gives the detector a bigger target to hit on than just the gold nugget alone. Once this is dug down to & the ground "halo" broken up, the signal can be somewhat reduced if the coil is still at ground level & not down into the hole. Sometimes it can even lead to the signal being lost if it was on the fringe of detection in the first place. So that is why air tests mean absolutely nothing out in the real world of gold detecting.

Sourdoughmoe: Steve H & phoenix hit the nail on the head & I am sure they have given you your answer.

Good luck out there.

JW :smile:

  

Thanks for the tips too, i did not take the halo affect into consideration.

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Hey Sourdoughmoe,

    I think your detector is running just fine, per all the conversations we have had.  I know many want to play around and test, test and re-test in test beds and such, but you really need to get out in the field.  

There is no question on all around sizes of gold, you will get your best performance with a PI.  Yes, you might have a guy find a small nugget you missed with his VLF, or a guy finding a nugget at depth you missed using a much larger coil.  You can "what if" yourself to death, so my personal advice is to get out there and swing in the areas you mentioned.  

If the gold is there, like you mentioned, I think you will do well and be glad you invested in a good Pulse Induction.  After the first run in the area, you will be able to answer a lot of your questions and plan the second trip much better.  

Just my personal thoughts.  Thanks again for the business and friendship.

 

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3 hours ago, Rob Allison said:

I know many want to play around and test, test and re-test in test beds and such, but you really need to get out in the field.  

Yep....out in the field is where it really matters & counts. Natural in ground undug gold. Not out in the field & burying "test" nuggets. That really means & proves very little. It is not the reality of getting out there detecting for gold.

Best of luck out there

JW :smile:

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Good thread. I also had a nug not register for me. Phase helped me do a dime check against his. 

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