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TDI audio and ability to use GPX coils, with ATX sensitivity would be a start of a half decent PI gold machine. 

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I have people in my family that throw a fit every time I want another detector, and so I have have to move slow.  I have the Equinox 800 - still learning that one and the Sea Hunter II which I hope to use while diving off the beach.

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12 hours ago, BeachBunnyTRHunter - DP said:

I have people in my family that throw a fit every time I want another detector, and so I have have to move slow.  I have the Equinox 800 - still learning that one and the Sea Hunter II which I hope to use while diving off the beach.

Sounds like you have the bases covered:  ground balancing IB/VLF for dry land and waterproof (to 200 ft / 60 m depth) PI for the water, with both capable of covering non-magnetite beaches.  Hold off getting anything more until a further need arises and get some brownie points with the family in the process.  😁

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Thank you. Great advice.  Though, no time like the present.  TEMPUS FUGIT, Latin for TIME FLIES.  So.... I did end up buying a 15 inch coil. I think I will put it to good use on the beach. Specifically in the wet sand near the water line.  

 

1/29/2021 addendum:  docsdetecting.com "SwingThing [improved]" device to take the weight of the coil off your arm works quite well with the Equinox set up – as it would with most detectors.  Considering the cost of a doctor bill, or the damage to your shoulder/restore otherwise – the $60 estimated charge for the above described device is worth it.  🙂

Edited by BeachBunnyTRHunter - DP
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  • 2 weeks later...

SeaHunter balances very well out of water with the larger 10x14 coil and control box mounted below and just in front of the cuff. The stock coil is bit easier in the water. If there isn't too much iron trash the SH is just easier on the beach as there is no fuss with ground balancing. I use that mostly but there are areas here the vlf is better as it has discrimination.

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Right, well, Ft. Lauderdale and Dania beaches are loaded with iron - other beaches here are likely to follow suit with iron on the beach.

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  • 4 weeks later...

Using Eric Foster's pulse  induction design(s) as White's did several years ago.  Build one from the ground up, utilizing the SL pkg., higher voltage battery packs (internal and/or external mounted) to last 4 hrs plus, course & fine adjustments, straight shaft, waterproof and a variety of coils & sizes, e.g., folded mono, elliptical, etc. I can only imagine. 

TC-AZ

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11 minutes ago, TC-AZ said:

Using Eric Foster's pulse  induction design(s) as White's did several years ago.  Build one from the ground up, utilizing the SL pkg., higher voltage battery packs (internal and/or external mounted) to last 4 hrs plus, course & fine adjustments, straight shaft, waterproof and a variety of coils & sizes, e.g., folded mono, elliptical, etc. I can only imagine. 

TC-AZ

Since were "baking our own cake, let's add a few more ingredients," such as a handheld probe option similar to the Minelab, the E-Trac version – maybe instead, The probe could use the new 3.7 V batteries – as could the detector.  Waterproof to 2 atm or about 33 feet – that gets 95% or more of in-the-water detecting with the battery compartment, separate from the electronics compartment – similar to the Garrett Sea Hunter II design.  Don't forget the display and circuitry that can show you 2+ targets simultaneously under the coil.  Perhaps even a pulse magnetometer attachment or ground penetrating radar attachment – wireless while we are at it, to tell you whether or not that deep target that you don't know whether or not it is iron is in fact IRON.   For example, imagine that whatever the WIRELESS, ground penetrating radar unit shows you comes up on the screen as an image of either a nail, Bobby pin, or whatever it is.  When you shut off the GPR/pulse magnetometer attachment, the display returns to whatever it was showing before.  I would envision that the attached gizmo would run off the same 3.7 V batteries and would be of similar shape to a fat Garrett carrot probe.

I think cheap GPR resolution is not quite there yet with metal detectors requirements but here is the current reality based on your 2021 technology:

reference source:  https://www.kbgprsurveys.co.uk/gpr-training/module-3-4-gpr-ground-penetrating-radar-resolution/

  • A 200MHz antenna has a wavelength of approximately 0.5m in soil, 10% of this gives a 5cm minimum diameter target in optimal conditions.
  • The same 200MHz antenna will be wideband if it’s a GPR, that means it transmits frequencies from 100MHz up to 400MHz. A 400MHz signal has a wavelength in soil of approximately 0.25m. ¼ of 0.25 gives a minimum target size of 6.25cm in optimal conditions.
  • Using the 10% of depth rule, that 5-6cm diameter target might not be detectable using GPR if it is buried deeper than 50-60cm.
  • Using the 1-inch diameter for every foot of depth rule, a 5cm diameter target (2 inches) might not be detectable if it is buried deeper than 60cm (2 feet).

 

– Now we're dreaming.

 

Note, and just my opinion, from what I have seen on the video tours of the Garrett facility in Texas, they need to build another building, if they are planning to produce anything that White's used to make or even anything new – their current facility looks fully utilized.

Let's not forget that Garrett needs to do an update on the ATX model to improve shaft and coil wire reliability and maybe some additional functionality.

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Wow, I like your cake better! I feel that the ATX is stagnant, to say the least... price too. With Tesoro & Whites closing their doors and the last companies to have PI machines, other companies abroad (excluding Minelab) have not produced new PI machines for whatever reason. Probably sitting on the back burner as not profitable. The customer wants a light weight, waterproof, bluetooth capability, muti-freq. w/interchangeable coils, etc., etc detector.

TC-AZ

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