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Minelab Double D coil in Mono mode

gavin		Posted : Thursday, 20 December 2012 9:57:46 PM(UTC)
Rank: Gold Ingot Groups: Administrators, Registered Joined: 20/02/2010(UTC) Posts: 1,326 Location: Christchurch Thanks: 736 times Was thanked: 535 time(s) in 287 post(s)		I've just read somewhere that double D coils can be used in mono mode on the Minelab GPX 4500. Anyone had any experience of this? Does it work well, or not as good as having a specific mono coil? I've got a Minelab 11" double D so curious of peoples experiences. Thanks in advance for any feedback :)
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kiwijw		Posted : Friday, 21 December 2012 2:32:35 PM(UTC)
Rank: Gold Ingot Groups: Registered Joined: 28/03/2010(UTC) Posts: 1,152 Thanks: 92 times Was thanked: 658 time(s) in 324 post(s)		Hi Gavin, Where have you been hiding?.....LOL :) Havnt you read your manual or watched any of JP's dvd's??? If using a DD coil & you flick the coil swith on the front end cap on to "M" for mono then it changes the DD in to a persudo mono coil. Meaning it transmits with both the DD windings but only receives on the left winding in mono mode. So when you get a signal & you try pin pointing it to the true center of the target it will be in the center of the left hand winding of the DD coil. Not in the true center of the whole coil. Also the mono response of the 11" standard DD coil that comes with the detector is therefore not a true 11" inches but only half of 11 inches. If using say an 18 inch DD in mono mode it will behave like a 9 inch mono. So it can be a very deadly sensitive option, just that the coil size is bigger than if using a dedicated mono coil. Especially in tight areas. I thought you would have sussed that one out by now. I dont use the option as I always run mono's as they are more sensitive & get better depth. Good luck out there. Regards John :)

gavin		Posted : Friday, 21 December 2012 2:50:26 PM(UTC)
Rank: Gold Ingot Groups: Administrators, Registered Joined: 20/02/2010(UTC) Posts: 1,326 Location: Christchurch Thanks: 736 times Was thanked: 535 time(s) in 287 post(s)		Cheers John... I think the trouble is that I get to use the detector so infrequently that I forget what setting options there are from one time to the next if it's been a while e.g. over winter :P Ah, so best to just get a bigger mono onboard then. Thanks for the advice, Gavin :)
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kiwijw		Posted : Friday, 21 December 2012 10:15:57 PM(UTC)
Rank: Gold Ingot Groups: Registered Joined: 28/03/2010(UTC) Posts: 1,152 Thanks: 92 times Was thanked: 658 time(s) in 324 post(s)		Hi Gavin, Yes we are lucky that our ground is pretty quiet & can use mono's all the time. A dedicated mono will always be better for us than a DD in mono mode. All the best out there JW :)