C$ & 10.5" coil for TID's +28 and higher

[Cal_Cobra]

I've been learning my C$ and one of my classrooms has been an old local park, but so far with the 5" coil I've only found modern coins (and the usual trash).

I'm thinking if there's any old coins left in the park, they must be deep. I was thinking about hitting it with the 10.5" coil, notch out foil and tabs, running sens as high as possible, and thresh around 0 to -20, and only digging TID's +28 and higher in hopes of finding older coins.

Does this sound like a good approach ?

Thanks,
Cal

 

[Mike Hillis]

Run about 810 with everything notched?

HH

Mike

 

[Cal_Cobra]

Hi Mike,

I didn't run the stock 8" there yet. I was under the impression the 10.5" would act like a DD coil, and might be a bit easier to manage with trash or many targets. Do you think the 8" would be easier to run then the 10.5" ?

Thanks,
Cal

 

[Jackpine Savage]

use the 8" with sens 8 and threshold -10 like Mike suggested. Notch out foil if you like but leave tabs notched in. In heavy modern trash you have to check out the higher reading tabs hits with a well centered sweep as some can be coins that will read higher with the better sweep. The C$ is one of the best if not the the best at picking out the higher conductors in modern trash that I have used.

Tom

 

[Everett Cavanah]

Jackpine has it correct

 

[Cal_Cobra]

Thank you gentlemen, I'll give it a shot this weekend with the 8" coil, foil notched out, sens 8 and threshold -10.

This park is the original main city park since the 1880's and has been a central gathering point every since, so there's bound to be some oldies there, but I figure they must be DEEEEEEP.

I'll post any good finds.

 

[Cal_Cobra]

I took off work a little early this evening and spent a couple of hours at the park. At this point I'm pretty sure that most of the park has a more recent top of top soil, as I'm finding new stuff towards the surface, but nothing old, and so far nothing deep.

I was under the impression that larger coils meant deeper searching, but after spending a bit of time searching for threads on the 10.5" coil on the C$, that doesn't appear to be the case here, as it appears to be good for ~ 6" of depth, but covers a large surface area like a DD coil in a narrow band. Is this correct, or can you set it up to go deep ? Would it make a good beach coil, or stick with the 8" ?

I plagiarized a few threads that Mike H posted to make help understand this coil:

You can control the detection field shape with the sensitivity control and the stability with the threshold control. That and the DD characteristics of the elliptical design make it a nice combo in these places. They are modern sites so depth isn't a concern but ground coverage is.

What I wanted was a 6" dime with a narrow detection pattern. Well it worked. I hunted most of the time at 250 and in the areas where the topsoil was thicker I bumped it up to 225. With Tracking on, everything notched in and iron disc at 99, I hunted in both all metal and disc mode. The 10.5" coil did just fine. I never felt like I needed to pick up my toysoro/cleansweep combo. I got decent separation, all the depth I needed and decent ground coverage. A number of dimes came up from 5" as did a very thin silver ring that id'ed as a large tab at a steady 18. I decided to keep it at 225 as I liked the audio better at 225 than 250.

 

[Jackpine Savage]

Cal,

the reason Mike used the low settings was to help eliminate the detector from picking up targets off the edge of the coil. In trashy situations at high settings most detectors including the C$ give a lot of signals and many of them will be targets near the edge of the coil as you sweep. The good thing is that despite this, the C$ will at the same time give solid signals on high conductors under or close to the center of the coil. You just have to be aware of this and is why I mentioned in my other post about keeping tabs notched in. Either coil will go deep but the targets have to be there. I think you should spend some time using a setting in the 525 range to get to know the machine a bit better. 525 will hit dimes easily at 7" with the 8" coil in heavy trash but they have to be there.

Tom

PS Some parks are littered with tiny foil bits, if thats your case something like sensitivity 7 and threshold -40 may be worth a shot. The C$ gives lots of options and is why so many still like the machine.

 

[Cal_Cobra]

Thanks Tom. I'm fixing to head to a local high school athletic field in a few minutes with the C$ & the 10.5" coil and see how it does. I might also swing by a local park I've been hunting and only finding modern clad (and the usual junk) and just to see how it compares to the 8" and 6" C$ coils I've tried there. From my testing at home, the pinpointing seems a bit iffy on the 10.5" (a quarter darn near hit 99 anywhere within the diameter of the coil, that's going to be a BIG hole - BUT smaller coins seemed to be right under the front arch, more or less...we'll see how it does in the field. It does seem a bit heavy, might have to hunt down a chest mount harness.

Brian

 

[Cal_Cobra]

Just got back from swinging. The 10.5" coil didn't work for me, too many targets (mostly junk). I switched back to the 8" coil, and picked up a couple of bucks of clad.

I find that the 8" and the 6" are pretty accurate for pinpointing, the 10.5" is a bit funky for PP'ing. I wonder why Fisher doesn't just mark the coil center, I like the way the BH coils give you a clear indication of the PP'ing focal point.

Brian