Got my SEF 10 x 12 coil for my MXT Pro, Should I cut my losses?

Discrimination Dave

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Sep 18, 2008
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I got my new Detech butterfly coil 10 x 12 for my MXT Pro. Yes I fell into all the hype. Deep is key for me here in Japan as well as stability and target separation.
The 300 coil that came stock is deep and I can usually run it at full gain or just about. However there is some red dirt not far from here that I cannot even hunt.
The first thing I did was an air test to compare to the 300 on the same machine. The sef did not like being powered up in the house. I could scarcely turn up the gain past half way. Depth looked to be about 60 percent of the 300. I got worried.
Took it out to the field to a spot nearby that has turned up a few goodies (old copper kiseru pipe, bita sen cash coin and copper trade ingot). When I powered up the machine she was extremely stable and quiet (maybe too quiet). I cranked the gain up all the way and the threshold was steady as can be. Got my first target quickly, +25-40 vdi at 9 inches. turned out to be what I think is scale armor. I have found them here before but even though it said 9 inches the target was actually about an inch deep. This happened again and again. I did find one cash coin and another scale armor but in both cases the depth read at 7-10 inches but were actually just a couple of inches deep. Something is not right. If a target at 2 or three inches reads 9 or 10 inches, what will an actual target at 10 inches read? It won't is my guess.
Honestly I feel quite lucky that I found anything at all. My ace 250 would do that!
Question is, any of you out there who have praised the sef on the MXT, is this coil defective?
I already have 200 bucks into this counting shipping. It would cost me another 40 bucks to send it back. Should I cut my losses.
Let me know what you think!
dave
 

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Treasure_Hunter

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Remember the depth read on a detector meter is based on the size of the target, detectors are actually designed to report on coin size targets, larger targets will read deep but be shallower... You don't say what size the targets were you dug though so I am just guessing they were larger than a coin.....

Are you talking about the SEF Butterfly coils? I can't speak for the Whites MXT but I use the SEF 12x15" and 15x18" Butterfly coils on my Minelab Excal and my Sovereign GT..... They both detect really deep targets. I personally pay little attention to air tests, I really don't remember the last time I saw a coin floating in the air :laughing7:..... Both the Excal and Sovereign are bad on air tests, but I have pulled up lots of targets 12-18" inches with them using the SEF Butterfly coils........
 

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Discrimination Dave

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Yes Treasure Hunter. The Detech SEF 10 x 12. Targets are coin size. My guess is the coil is defective but If I pay to send this back and they send me another that operates the same then I will have really crapped the bed.
 

wingmaster

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Any coil different than the one that comes with the detector is going to be off in the depth measurement as the unit is calibrated to coil it comes with. You said you was able to detect with the gain set high I would air test out in the field to see what actual depth your getting with the gain cranked up and as long as you get good depth I wouldn't worry about what depth it says as you'll get used to what depth it really is once you use it enough. Even the white's smaller coils the depth is way off but it VDI's the same, the white's D2(10"DD coil) is great for depth, I was trying to get a little more depth over the D2 and bought a detech 13" ultimate DD coil which gets about the same depth but it does cover more ground per sweep for large open area's and it does give those deep silver dimes on edge a little better target response at least enough that I dug a few that I passed with the D2 because they didn't sound good enough to dig like deep trash. HH
 

treasurehound

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I have the 10x12 SEF coil on my MXT PRO and love it. I have used the 6x10 and 10" D2 coils and gone back to same area I hunted with those coils and hunted with the SEF coil and found much more deeper finds. You do have to hunt really slow to hear those deep signals. I highly recommend this coil.
 

Giant056

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Even with the D2 coil I hunt very slow with my V3i to hear the really deep stuff. I've never had the 10x12SEF but I've been pondering on getting one cause I have both the V3i and MXT.
 

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Discrimination Dave

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Thanks for the replies. I went out with both coils and switched them out from time to time.
The SEF is much more quiet and seems to reach down as far.
After I got used to the SEF, the 12 inch was too noisey.
I guess money well spent.
I have found good stuff with the new sef, all be them shallow so far.
thanks.
 

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