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TDI Pro And SL Difference?


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Is the main difference between the TDI Pro and SL is gb course and fine adjustments? Is there any power difference between the models? An old friend might be selling his TDI and I believe it is one of the older Pro's and I might snag it.

Also what 3rd party coils work with them?

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The big battery system in the Pro gave it lots of raw depth ....Deepest Detector on a saltwater Beach I ever used .......nothing like The SL or Even The Latest TDI Beach Hunter ......I’m taking straight PI mode no ground Balance 

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I only have ever used the TDI Pro with the big battery,never really liked the 'S' shaped shaft of the 'sl' version,mainly use mine also in straight PI mode for the extra depth but when i am on my roman trading villa site which is basically like a 40 acre black beach but 70 miles inland then i will use it in target conductivity mode and must admit although i loose a small amount of depth it does work very well at discriminating out the non desirables.

Regarding coils for the TDI Pro,although i do have the Whites stock coil and the 7.5DF ones the main ones i use are Minelab Mono coils and also the coils made for Jimmy Sierra by Miner John i bought some at a crazy low price brand new when he closed down a few years back,the largest one i like using is the 20'' Sierra Grande Mono.

Wont ever part with mine as they are getting very hard to get hold of these days.

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I have the TDI Beach Hunter and love it. My understanding is that it is an sl in a waterproof package (hardwired coil).  I made a couple of 16 volt battery packs to use with it to get a little more depth and sensitivity. It seems more sensitive to low and mid conductors than my old Dual Field.

I heard that the TDI Pro operates at a higher voltage and is a little less stable but gets unsurpassed depth. It is not waterproof so you have to be careful near the water and in the rain.

If you don't buy it I may be interested. Thanks for posting about it.

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I had looked at the SL and seeing what depths people were getting I wasn't super impressed. I would be using it in land only anyways, not crazy about bring a machine with exposed pots to the beach. I have my SH with 10x14 coil that is close to the TDI Beach in the wet, just doesn't find the tiny stuff but good on rings, coins, nails, cans, pull rings etc. 🙂

There are a lot of old low land areas near me that have gobs of bog iron where a PI will just do better and an IB.

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"I have my SH with 10x14 coil that is close to the TDI Beach in the wet, just doesn't find the tiny stuff but good on rings, coins, nails, cans, pull rings etc. 🙂"

The TDIBH with my upgraded battery is pretty good on small targets. I agree that the depth on high conductors is good but not as good as I would like. It seems to hit a little deeper on smaller gold and other low/mid conductors. It does better on gold chains than my other pulse detectors but won't see the thinner ones. Not sure about the TDI Pro but I think it would see the smaller targets just as well if not better.

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10 hours ago, RickUK said:

I only have ever used the TDI Pro with the big battery,never really liked the 'S' shaped shaft of the 'sl' version,mainly use mine also in straight PI mode for the extra depth but when i am on my roman trading villa site which is basically like a 40 acre black beach but 70 miles inland then i will use it in target conductivity mode and must admit although i loose a small amount of depth it does work very well at discriminating out the non desirables.

Regarding coils for the TDI Pro,although i do have the Whites stock coil and the 7.5DF ones the main ones i use are Minelab Mono coils and also the coils made for Jimmy Sierra by Miner John i bought some at a crazy low price brand new when he closed down a few years back,the largest one i like using is the 20'' Sierra Grande Mono.

Wont ever part with mine as they are getting very hard to get hold of these days.

 

2 were for sale beginnin of december in Staff shop they went not quickly but they went

 

 

RR

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There is a TDI, a TDI Pro , and a TDI SL. In simple terms, the TDI Pro is the TDI with an added fine ground balance control mainly to address areas of extreme mineralization.  The TDI SL is a scaled down (hardware to software) TDI. With an upgraded power supply it can nearly match the performance of the TDI. The TDI series will accept coils made for the Minelab SD and GP series detectors. But tolerances are tighter on the coils made for the Minelabs and the TDI produced coils will not work in reciprocal. A vast amount of coils are available. You as the end user has to decide what your target goal is and which coil will best achieve that goal.  Karelian did a post on this forum regarding a number of coils he ran through a test, a good starting point. Coils tend to be more expensive so pick wisely.

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There have been many threads here that discuss the TDI's, and especially mods for the TDI/SL.  I recall some comments that not all TDI/SL (including the SPP variant) could be juiced up by simply adding more voltage.  Those concerns claimed the date-of-manufacture was a tipoff to whether or not a higher voltage would help.  (I don't know if those claims were solid/verified, though.)  Reg Sniff was the expert outside of White's but unfortunately (in many more ways than just this) he's no longer around.

The only issue with using GPX coils (including aftermarket/3rd party versions) on the TDI's that I'm aware of is that sometimes the DD's don't work well on at least some TDI's (whether it's model dependent or just individual unit variation dependent, I don't remember).  But the monos (AFAIK) work great.

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22 hours ago, GB_Amateur said:

There have been many threads here that discuss the TDI's, and especially mods for the TDI/SL.  I recall some comments that not all TDI/SL (including the SPP variant) could be juiced up by simply adding more voltage.  Those concerns claimed the date-of-manufacture was a tipoff to whether or not a higher voltage would help.  (I don't know if those claims were solid/verified, though.)  Reg Smith was the expert outside of White's but unfortunately (in many more ways than just this) he's no longer around.

The only issue with using GPX coils (including aftermarket/3rd party versions) on the TDI's that I'm aware of is that sometimes the DD's don't work well on at least some TDI's (whether it's model dependent or just individual unit variation dependent, I don't remember).  But the monos (AFAIK) work great.

Must admit i have never used a GPX DD coil on my TDI Pro,only ever used the Mono coil and as you have mentioned they work a treat,one big advantage with using the GPX Mono coils is that you can pick them all up relatively dirt cheap brand new as most of mine cost me peanuts and i mean peanuts.

The TDI Pro is plenty deep enough for my needs and that is mainly on specific sites mainly my roman trading villa site,if i want the same depth or deeper then my one of my Nexus machines come out to play as that then offers me the same depth as a Pulse but with full discrimination its a no brainer really.

 

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