F-75 5" DD vs. 6.5" eliptical

[RushinPA]

Looking for a small coil to compliment the standard coil. I was interested in side by side comparisons. Anyone have an opinion? And,,,is the 6.5 a DD coil? I have heard good news about the 5 DD getting good depth, but have heard little about the 6.5.

Thanks
Chuck

 

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[The Punisher]

I also would like some info on this.....

 

[Charlie P. (NY)]

I'm really liking my 6.5" elliptical in trashy areas. Also works great in tight areas like foundations and spots with thick weeds and saplings. So much so that I haven't had it off my F-75 in a year! Haven't tried the 5"DD.

I'm a fan of DD coils and can imagine both as winners.

 

[Jim Hemmingway]

I've used both the 6.5" elliptical concentric and 5" DD coils in the all-metal motion mode for prospecting applications. Both coils are very good options for improved sensitivity to small stuff and surprisingly don't lose all that much depth on large deeper coin size targets. As Charlie notes, they're great for working trashy areas, around obstructions, and getting close to fences.

Both coils significantly reduce EMI in urban settings and both see much less ground mineral compared to the stock 11"DD = much improved stability that consequently allows for using higher gain settings. Theoretically at least, over extreme ground minerals the 5" DD should have an advantage... but over my ground that generally runs at 0.3% equivalent magnetite on the Fe3O4 bar graph readout... if anything the 6.5" elliptical has ever so slight a depth / sens advantage.

What I cannot tell you is how well each comparatively works using discrimination modes. I've not used them for coin hunting yet. I doubt you can go wrong with either choice, but I have formed an impression from reading NASA Tom's coin / relic forum that the guys there generally prefer the 5"DD for their applications. Good luck and HH.

Jim.

 

[Sandman]

HI Jim, Been a long time.

 

[Jim Hemmingway]

Hi Dennis... it sure is good to hear from you again. Hope you are doing well and that all is as good as can possibly be with you!!

I guess you know that Steve's AMDS Adventure Forum is closing down soon. Been there posting away for several years, but now have returned here for good. I've been posting a fair bit over on the Metal Detecting for Gold sub-forum recently, and hopefully will get back into the swing of things on a wider basis shortly. We have a great bunch of people here, but I have noticed a few longterm members seem to be absent from the forum. Or at least I've yet to see them.

We'll be seeing you Dennis around and about on the forum, I've always enjoyed your contributions. It was also nice to see an old favorite in Charlie P. above.

Your friend... Jim.

 

[Jim Hemmingway]

A couple of threads I've found for you guys regarding the small "shooter" coils...

http://www.treasurenet.com/forums/fisher-research-labs/224672-fisher-f75-ltd-5-coil-testing.html

http://www.treasurenet.com/forums/fisher-research-labs/293400-f-75-6-5-concentric-vs-5-dd-coil.html

Jim.

 

[Charlie P. (NY)]

Hey-ya Jim & Dennis.

The 6.5" Elliptical is great for coinshooting. Especially in the parks and fairgrounds I like to poke through. Great seperation. Surprisingly it's also good in the woods and around creeks (old fishing holes) as it doesn't snag on weeds and brush like the larger "halibut skeleton" stock coil. Does lose some depth but will still mark a dime at 8" if you're paying attention.

 

[Jim Hemmingway]

Doggone CharlieP… I wish you could see the smile on my face just now. It is good of you to take a moment to say hello. Maybe I’m a sentimental old fool… but thankyou.

I also really like the 10” elliptical concentric on the F75. I don’t think it loses much measurable depth on coin size targets compared to the stock 11” DD coil here. But it’s a better iron discriminator, a bit better with EMI in town, and for prospecting it responds to much smaller targets… right down to sub-grain gold at or near the surface… that the 11” DD cannot possibly see. The 6” elliptical concentric “shooter” coil enhances that performance… but also makes quite a difference with ground minerals.

It has always amazed me how well the shooter coils will see coins at good depths in my test plot, especially over low conductive nickels. I like to imagine they’re big gold nuggets!!

Jim.

 

[Charlie P. (NY)]

I'd set you up to a beer - but you'll have to serve yourself. ;-)

When I'm pulling nickels I figure me and the machine are doing our job.