So, what do *you* think?

[silversmith]

I watch some guys move very slowly over the ground. Maybe moving a half-inch per loop swing. I see other guys advancing a whole loop diameter per swing. The seem to have the same number of targets at the end of the day. Now sure if you get into a hot spot you want to slow down work the area well. Years ago a couple I detected with were slow movers. Me, shucks I was all over the area. I'd look at them and they were still there, hardly moving. But again, at the end of the hunt, they'd show me their finds and they had as much as me. So maybe, it's just time over the ground with the detector and luck. I'm thinking of getting a DD loop for my B.H. Maybe I get a better scan width than the quarter width at depth. Might get 3 " down at the 5-6" depth. What do you think? Opinions welcomed!

 

[Uncle Willy]

DD's throw a wedge shaped signal the full length of the coil and detect as deep at either end as they do anywhere else.. That's why you can only detect side to side with them.

Bill

 

[Furious T]

Depending on how mineralized your soil is, you'll normally get better depth with a concentric coil than a DD. Hence the need to go slowly if you want to cover the ground carefully. Experiment with your sensitivity on different settings....try detecting with low discrimination to see if the ground is saturated with targets (good or junk). Dont be afraid of experimenting or going over the same ground with different settings i.e. discrimination and sensitivity. Try All Metal if the targets are few and far between. Take your time and enjoy yourself. HH Sapper

 

[nw1886]

Guess it would depend on how "old" the ground is. More modern sites seem to have the targets within the top few inches and don't require an extreme lap pattern. Older sites do and require not only a narrower pattern but also a slower swing speed with looser interpretation of info. Use BOTH styles of searching to adjust to your particular site.
There is one big exception to this...trashy sites where jewelry is expected. Small coils and plan on lots of retrieval. It's largely a numbers game at that point and make sure you are set up for it with your best pinpointing skills and also a powerful pinpointer. Play with your settings, enjoy your aluminum collection, love your gold, and use SP20.

 

[Ron from Michigan]

Silversmith,I think the type of metal detector used will be the factor to decide your effective sweep speed.I have used a lot of different type of detectors and prefer a detector with a slow sweep speed.Most good clad machine have a fast sweep.I find the double D coil on a Sovereign is probably better at target separation than most detectors I have used with a concentric coil.A lot of people will use Concentric coils on metal detectors that the manufacture has a double D stock or vise versa and in most cases these after market wonders don't work well.The advantage of the concentric coil it will cover most areas faster because of the sweep speed than a DD even with a wider scan.My choice for my type of hunting a DD coil,which works better for me with the parks I hunt.By the way I too am still trying to find that perfect metal detector or accessories combo,which keeps a lot of dealer's in business.Good Luck.

 

[JB(MS)]

I scanned the photo from a Garrett ad in one of the treasure mags a few years ago. It shows the difference in the scan patterns of concentric and widescan, or DD, coils. I've had quite a few of both and in my mild ground there's no contest in depth when comparing same size concentric and widescan coils, the concentric is deeper. In moderately high to higher mineralization a widescan will go deeper because it sees less mineralization, but widescans don't discriminate as well because, according to George Payne, they shift the phase value of targets slightly. But after having basically bad mouthed widescan coils I have to admit a 6X9 widescan is one of my favorite coils to use. It doesn't go as deep on the same detectors as the 8 inch concentric, and it's harder to pinpoint with, but I can swing it fast, cover more ground and it gives some subtle audio variations that aren't present when using the concentric coils.
[attachment 125117 coiltransmitfield.jpg]

 

[silversmith]

Ok, thanks alot for all the great input. I went ahead and bought the 11" DD loop for sale on E-bay. I't was very expensive compared to concentrics but may well worth the outlay. The ad claims it for an F4 but will work well on all B.H. detectors. I just bought a 7" concentric coil that claimed that and indeed it works well on my Big Bud Pro Select 220D made by B.H. (mouth full!) It will be a real joy being able to go into a new place and check it out quickly with the wide search coil. Again thanks and I'll up new about the coil as I use it.

 

[silversmith]

Well, it cost me a pretty penny! It's mounted on the detector. This week I'll "give'er a go.

 

[zeekeys]

Hi Silversmith
I don't know about you but the older I get the slower I move and swing. I have to change detectors to fit my movements. I had to sell my Garrett because it would shut off before I got a full swing in. ....Z