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DD VS Mono (depth)
Posted by: Jim Robertson
Date: September 02, 2018 06:54PM
My I think simple question is. How much more depth % do you get in Mono on a pulse machine? Ie TDI,GPX

Re: DD VS Mono (depth)
Posted by: doc holiday232
Date: September 15, 2018 10:56AM
Hope some of the testers will show up.

Re: DD VS Mono (depth)
Posted by: filternozzle
Date: September 15, 2018 11:57AM
I don't know the answer but I do use both TDI and GPX. I only have the standard coil that came with my TDI. With GPX I use DD, AI (Anti Interference) and Mono. Using the same size coil the least depth is with the AI coil, the deepest is the Mono followed by the DD. I think the % difference is variable depending upon a multitude of things like ground, wet or dry conditions, target material, target size and shape etc..

I will use the best coil for the conditions and type of target I'm looking for. The difference may not be much between DD/Mono but using a mono for a little extra depth could be the difference between finding a really good target or passing it by.

Happy Hunting
Minelab: GPX-5000, GPX-4500. Whites Pulse Scan TDI. Nexus: MP, Standard Mk II & Ultima. Nautilus: Silver King, DMC, DMC II, DMC-IIB & DMC IIBa.

Re: DD VS Mono (depth)
Posted by: Jim Robertson
Date: September 15, 2018 12:13PM
Thanks I do relic hunting in Va. and have only used the DD. It is a hunt that they have twice a year and many of the sites we have been to more than once. I was thinking the Mono may be the way to go to find targets that we have missed with the DD. I use the 4800 at those hunts. Thanks Jim

Re: DD VS Mono (depth)
Posted by: Mega
Date: October 01, 2018 04:26AM
I cannot say as i have never used a DD coil on my TDI Pro,nearly all my coil that i use are Mono and mostly made for the GPX as well,the main ones that i use all the time are the Coiltek 14x9 mono,15x12 Commander mono and the 18'' Detech mono,and occasionally the 20'' mono that was made for Jimmy Sierra by Miner John.

Cannot recall the last time i used the stock 12'' DF coil but i do also use the 7.5'' DF coil as well,the 12'' stock coil as i under stand it is a very good all rounder,but they are not DD coils,only other coil that also gets used as well is the 9x5 folded mono but although its a mono coil being that its folded does reduce the depth a little,but it does not get EMI problems as much.

Dont plan on getting DD coils either,only reason i use Mono coils that had been designed fpor the GPX series is that it offers a much wider coil selection and as no one really uses them as such on the GPX because the discrimination setup only works with thye DD coils,so you can pick up Mono GPX coils reasonably cheap because of this.

But still my favourite for the TDI by a big margin is the Coiltek 14x4 mono,its as light as a feather as its foam filled and love the ability that is pinpoints very well using the edge of the coil and it was also very cheap brand new,the coil that is use the least is the 20'' JS mono coil,only reason i got that is that when Jimmy Sierra closed his website down a couple of years ago he sold off all his coils at crazy low prices and even including shipping over to the UK and other costs involved was still stupidly cheap,so although not used much but do not have a massive amount of money invested in it sitting around for long periods of time,the occasions that i have used it,it really does punch deep but of course only on large targets,forget about individual coin size items.

An ageing reprobate awaiting the Reaper's visit, trying to do interesting things until he calls....

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