Large dd's on the gpx series

Anyone out there using 18 inch dd coils on either the 4000 or 4500, i sold my 18 mono awhile ago, and am thinking of getting another big coil but the shops are still out of stock [mono] but have dd's in stock so was thinking of giving it a crack, dd in normal timings any advice would be good.

Thanks

You'd be lucky to find anyone with a coil in stock, let alone a DD, as the manufacturers are making monos, because of the fact they are in demand. I personally don't use DD's and haven't for a very long time as I hate the wimpy response they give in comparison. The GPX series of detectors are aimed towards mono coils to suit the extra timings, but need a DD coil to allow Cancel mode or Discrimination to work, neither of which I use. I have a 24" DD coil which is damn heavy (2.2kgs) and needs 2 bungy straps and a damn strong resolve, but it gathers dust in my shed. If you can run Normal timings on a GPX then a mono coil is the answer from my perspective. Cheers.

Thanks q sandy ive been running the 11 inch dd in normal timings on the 4000, gain around 8-9 and it is noiser than even the 18 mono when in ss mode but i was thinking with an 18 dd it would maybe smooth out some of the ground noise compared to the smaller coil and if i really had to i could put the gain down to 7, its all a trade off i know but normal is much more powerful than ss but with the gpx's you can tweek them down abit when in normal timings,

Also the consensus is that ive heard is most people with the gpx series dont use dd's, dont even give them a go because they have been told mono is the only way, but with my limited experience ive found more gold with the dd v mono about 15+ to 6 or so, i dont keep count but i cant write off the dd's because ive been more sucess full, including using the 14 inch mono with no gold for days on end then wacking on the 11 dd and finding a 4.5 speci in 10 mins,

somone must be out there using the dd's in normal.

The other week with my 4000 I did a small area with deep leaf litter with the 14inch mono in sensitive smooth with the gain on 9. Then I did the same area with the stock 11' DD, sens smooth with the gain on 15. I got an extra 6 targets with this set up. (No gold).

After the first couple of hours the emi became too much for the gain on 15 but the target noises sounded different and were repeatable over the huimming interference so I persisted. I believe I was getting deeper because I was sure I had gone over those spots already with the 14 inch coil.

I don't know if this was the right thing to do but I tried it. Am I supposed to use normal timings with the DD coils?

Dicko..

i have my standard coil on my 4000 and have found my first bit with it on a digging last sunday...i'm still working out all the settings as i have only had it for 3 to 4 weeks...i'm happy with the coil on it at the moment, but i'm going to try a 8" coil to see how it go's. i'm off to maryborough on friday to get showen how and what settings are the best...should be good.

yeah chuck it in normal, ive treid the dd in ss and still get gold, ive wonded around with mono's and get sweet fa, im saying in well thrashed ground i waltz onto with the 4000 and find a nugget almost all the time with a mono nadder, thets why im asking for any feed back from jp, qsandy and any other experinced operators, and i think they may not have geiven them [dd's] ago but im only asking.

And choppa they do say that most gold has been found with the 11 inch dd so that says somthing not to menchion that minelab still send out those coils with their new units.

Hi All
Large nuggets at depth came out of the ground fairly regularily here until around the time the 3500 was released and Monos became the coil of choice. Previous to that the DD ruled.It was DD ground then and Im pretty sure it still is now.
Cheers Dig

I,m glad this post was started as today I was thinking to try my DD for the same reasons.I,m finding mainly small gold but used to find larger deeper pieces with the old 2100 and DD setup.
Tomorrow I will try it in the same ground and see what happens and let you know.
Steve

this was found by a friend with a sd2100 with a standard dd coil
https://s589.photobucket.com/albums/ss332/stoppsyxr8/?action=view&current=2010_09040006.jpg&newest=1

Ok I tried the DD today.1 nug for 0.5g.The main difference was in the size of the trash bullet etc.The DD virtually didn,t pick up any of the really small stuff.The DD was a lot heavier than the NF and less sensitive but a lot better with EMI.Couldn,t notch up the gain as a bit noisy on the ironstone.Will be trying a NF16DD on flat ground in the next few days.
Steve