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This maybe a newbie question but, what is the difference in the 12" Dual Field Coils pictured here other than the black and white labels?  Is one 1st gen. or 2nd gen. or something else?

Thanks, TC-AZ

2033275659_TDIBlackLabel.jpg.bfa7d6d0fb6b7b3439d7f8f8328e33fd.jpg  780771244_TDIWhiteLabel.jpg.47f7785a376f4e87d8cc834715db5ded.jpg

 

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Those DF coils really sucked down the battery juice causing the TDI to become un stable (and difficult to ground balance). I would check the batteries every couple hours of run time.  The smaller DF coil for sure better than the larger one.

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57 minutes ago, Hard Prospector said:

The smaller DF coil for sure better than the larger one.

Better in what way?

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Is the battery drain issue and lack of power issue of larger coils also applicable to the TDI Pro and also the TDI SL?

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11 hours ago, Cascade Steven said:

Is the battery drain issue and lack of power issue of larger coils also applicable to the TDI Pro and also the TDI SL?

Mostly the SL as it ran (mostly) on AA's with the usual White's slide in clam shell..........but even the Pro with its larger rechargable battery pack was still no depth demon.  You could never trust the low battery light indicator to signal when the voltage dropped below the point where the batteries should be replaced or recharged. Every 2 hours of run time I would check or change them out in the field.

If nugget shooting with this detector  its been my experience that loops 6 x 10 or SMALLER  were most effective, especially the (5 x 9) folded over mono.  The larger DF coils were the worst  (unless looking for .50 cal musket balls or civil war belt buckles).

The TDI series was a good PI that held lots of promise to evolve. Unfortunately  chief engineer Dan Geyer,  who ran the project and was advancing it,  suddenly passed away at the worst possible time. Turns out he was irreplaceable.

 I believe the  loss of this brilliant man began the down hill slide not just for the TDI but for White's in general.

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Hard Prospector:  Thank you for your insight.  I have a TDI SL and am still learning the details of this machine.

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TDI is unbeatable machine.
 There still is nothing that will match them for depth on gold items!
They are no other PI units out there today that can equal it's performance.
 Those loops are rare, you are so lucky to have them.

Remember that well,  any coil has a name "TDI" works extremely well, just which one that needs to use in right place. 

I wish you all the best🙂

Hamid

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