Coil questions and information

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Leroy said:
Gold rat, I too can vouch for DD gear. I have the harness and the bungee and 3 other of his items,they are strong and comfortable, and as Bogger said, a great guy to deal with.

Thanks to Bogger and Leroy for their experiences with Double "D" products . I have tried Minelab Harness , Swingy Thing (USA) and a bungee and strap (UK) all uncomfortable for me . Will be buying one shortly .
Noticed online a manufacturing address , can you purchase there or only on line .

Appreciate your help ,

Cheers
goldrat
 
My X-TERRA came with a 9" Concentric and 6" Concentric coil!
At the moment iam keeping away from the beaches (tooo windy cold) so mainly grassed areas! Would i be better with the 6" or there is not a big difference between coils? Also where on a 6" is the pinpoint? Do i dig in the middle of the coil as like the 9" or the top of the 6"? One last question if i do change coils it seems to look like a simple thing to do, do the tones change? From coil to coil. Both are 7.5
Cheers
 
The 9" concentric is a treasure coil. It is likely that the 6" coil is for use in gold detecting. Check the coils, they have a Frequency written on them.

9" Concentric 3.0kHz - Treasure
6" Round 7.5kHz - Gold/Treasure etc etc

Have a look at the Minelab site http://www.minelab.com/anz/accessories/by-detector/x-terra-series#sec259699

These are all the 705 coils, their frequency and use.
 
The target signal should be at the strongest in the centre of the coil, just as it is with the larger 9" coil. The 6" is mainly designed for working junky areas, whereas the 9" should give a depth advatage as well a bit more ground coverage than the smaller coil. The downside of the larger coil in junky areas is the lesser ability to seperate out targets, as it may in some circumstances end up with several targets being picked up at the same time under the coil. The smaller coil will allow you to pick up good targets a lot closer to nearby junk, and allow a more accurate ID.

I wouldn't think the tones would be any different between both of them.

Here's a diagram showing the difference in detection field between a double D coil, large concentric, and small concentric. The concentrics offer up a cone shaped detection field and more accurate target ID's, whereas the DD will offer better handling of mineralisation, and will be easier to seperate out targets with its blade shaped detection field (down the centre axis of the coil). Hope that helps a bit. :)

1468746695_images-3.jpg
 
Goldpick said:
The target signal should be at the strongest in the centre of the coil, just as it is with the larger 9" coil. The 6" is mainly designed for working junky areas, whereas the 9" should give a depth advatage as well a bit more ground coverage than the smaller coil. The downside of the larger coil in junky areas is the lesser ability to seperate out targets, as it may in some circumstances end up with several targets being picked up at the same time under the coil. The smaller coil will allow you to pick up good targets a lot closer to nearby junk, and allow a more accurate ID.

I wouldn't think the tones would be any different between both of them.

Here's a diagram showing the difference in detection field between a double D coil, large concentric, and small concentric. The concentrics offer up a cone shaped detection field and more accurate target ID's, whereas the DD will offer better handling of mineralisation, and will be easier to seperate out targets with its blade shaped detection field (down the centre axis of the coil). Hope that helps a bit. :)

https://www.prospectingaustralia.com/forum/img/member-images/1695/1468746695_images-3.jpg

Well done GP, Nice Post,

J
 
Hi guys i have been down the beach wit my new gpx5000 and found lots of fishing gear empty old cans pieces of rio etc anything but a gold coin ha haha anyway im using a coiltek goldstalker 14"x9" mono but was wondering if thats the right one for that environment as i have plenty more coils 2 choose from any help from you guys much appreciated Cheers
 
Most people would probably use a DD coil for a bit of extra stability & also to allow the use of some discrimination in trashy areas. Either way you will be doing a lot of digging & deep digging on a beach with a PI detector.
 
not many bottle lids and cans in the water just treasures ,dont know much about gpx5000 but try mono coil
 
mbasko said:
Most people would probably use a DD coil for a bit of extra stability & also to allow the use of some discrimination in trashy areas. Either way you will be doing a lot of digging & deep digging on a beach with a PI detector.
Intersting. So if I use my sdc on a beach will it detect a lot deeper because of the salt acting as an electrolyte and sending back a stronger signal than it would normally ?
 
GPX 5000 On the Beach :eek: :eek: Bigga Me.

You wouldn't go any deeper if you used a Drilling Rig and Took Core Samples,

Ava good feed and get to bed early the night before, Your gonna need it, LOl

John
 
Haven't used my gpx on the beach but using my garret infinium and a mono coil I have dug deep... Real deep, 2ft for bobby pins, I think the gpx would punch a lot deeper than the infinium, I would try the mono coil but would expect to swap to a DD if needs be, DD coils are brilliant in there own right and are a very useful tool

Edit for spelling
 
Wishfull said:
mbasko said:
Most people would probably use a DD coil for a bit of extra stability & also to allow the use of some discrimination in trashy areas. Either way you will be doing a lot of digging & deep digging on a beach with a PI detector.
Intersting. So if I use my sdc on a beach will it detect a lot deeper because of the salt acting as an electrolyte and sending back a stronger signal than it would normally ?
No - less mineralisation to combat in most dry sand/beach areas. Wet sand would prove more difficult but the GPX & SDC have salt timings & generally handle mineralised/difficult ground conditions better. Salt can be an issue for PI detectors not enhance things. You would have to adjust to suit your local beach conditions but in most cases a PI can punch very deep in sand but there would be a lot of discriminating VLF's that would also get good depth too (in most cases I would choose a discriminating VLF that is known for beach work/wet sand handling over a PI).
Heres some good write ups:

https://www.minelab.com/anz/treasure-talk/the-power-of-salt-gold

http://phasetechnical.com.au/detecting-mineralised-black-sand-beaches/
 
In the Dry sand most VLF's will give results similar to like they do in Air Tests, The down side is the sand keeps falling back in the Hole, lol .

John.
 
Gpx5000 in Salt Gold is the only Minelab PI that will ground balance out the wet sand. Use a small mono and it's deadly on rings. When it's trashy I use a DD and as Mbasko said gives you the versatility to use a bit of Iron Reject, or Cancel mode if there's too much EMI about. P.s. Sens Smooth timing may ignore a lot of deep badly rusted iron.

Would be great if the control box was at least rain proof. I'd probably use it a lot more.
 
Hi all can some one please tell me what the difference is between a mono and a double D is . I have two here that look the same one has mono commander the other has gp series. Is the gp series a double D ? They are both round.
 
Compare the cables on each, you'll see on the Commander Mono that the cable is perfectly round, if the GP Series appears a little flatter in circumference then it's a Double D, otherwise it's a Mono.

They each have their uses, see the following taken from one of my earlier posts on the forum.

Double D (DD) searchcoil

  • Good for coin, jewellery, relic and prospecting[/*]
  • Good for highly mineralised ground and trashy areas due to there narrow detection field[/*]
  • Good target separation[/*]
  • Good ground coverage, minimal overlapping required[/*]
  • Cant really think of any cons for DD searchcoils[/*]

1470985727_9g8om0.jpg


Monoloop searchcoil

  • Good for coin, jewellery, relic and prospecting[/*]
  • Greater depth penetration over a DD coil of the same size[/*]
  • Good ground coverage, medium overlapping required.[/*]
  • Difficult to ground balance in highly mineralised ground so can be noisy in certain conditions[/*]

1470985741_2n6r7zn.jpg


I hope that helps.
 

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