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Is there anywhere on this site that has the research or post made from Reg Sniff pertaining to
TDI depth in relation to battery voltage?  I remember somewhere that stated the reason the original TDI had greater depth capabilities was the increased voltage of the batteries not necessarily the model number.  It also had information in relations to voltage limits/performance issues.

Just thought I'd ask.

 

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Not sure this is what you are looking for but there is some great info in it:

 

 

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This one is probably a good start - the bottom line was that even 25v. Didn’t increase the depth more than perhaps 10%

https://www.tapatalk.com/groups/whitesgoldmaster/tdi-battery-voltage-t870.html

Here’s a quote from “Geo” on the geotech forum

I tried the (first) TDI model at 25V without problem.
Difference at depth was very small so the stantard battery (14.8V) is the best solution.
Of cource i believe that the constructors knows better than uslol.gif

https://www.geotech1.com/forums/showthread.php?23030-TDI-SL&highlight=TDI+battery

 

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Careful reading of some of Carl's writings the original TDI and the SL version use the same board and components.  Same circuit regulation and possible outputs.  He admitted the original TDI was quite a bit more sensitive in terms of depth over the SL version.  The main exception is the amount of current applied to the coil TX circuit.  All things staying the same, the TDI might air test (no EMI) a target at 16" verses the SL version (no EMI) 12".  This difference amounts to 25%, which is more than enough, to pursue improved battery voltage related improvements.

 

 

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Where did you see 16" verses 12"?

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That is my own observation using the standard 12" dual field coil with a steady threshold hum.

I can squeeze more out of the machines if I can tame the EMI but sometimes that can't be done.

 

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Good example of the TDI Pro version.  There might be something wrong with my SL version, but I can't obtain the depth of the PRO version.

 

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Thank you for the reply Mark.  I wish I could be more help to you on this subject but to tell the truth target depth was only one of the things I looked for when I picked the TDI SL and I was willing to give up "extreme" depth in order to satisfy the other requirements.  I have seen the posts you are looking for though and if I'm able to find them I'll post for you.  Good luck sir.

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On 4/17/2019 at 1:22 PM, Mark Gillespie said:

Is there anywhere on this site that has the research or post made from Reg Sniff pertaining to
TDI depth in relation to battery voltage?

Is this what you're looking for?

 

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4 hours ago, GB_Amateur said:

Is this what you're looking for?

 

Thanks, I have one rechargeable battery that has gone bad.  Taking my time and cutting the glue loose I can see the case has the capability of holding different kind of batteries with some modifications.  I"m looking into both the Panasonic and Westinghouse batteries.

It might be of interest, the voltage of a freshly charged battery pack is only 11.5 v that is lower than using new AA batteries in the optional battery pack by quite a bit.

 

 

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