X-70 Question (What coil is best for old home sites)?

[Prospector]

I have the stock coil and the 5"x10" DD for jewerly and beach hunting. I would like to hunt some old home sites for silver, relics and copper. Which of the following would be better: the stock coil, 10" DD, 6" or the 9 1/2" 3hz. coil? I have heard that the stock 7hz. coil is just as deep on silver and copper as the 3hz. I know the 6" would do better in trash, but may loose depth. Really don't know that much about the 10" DD. I am trying to avoid having to buy a lot of extra coils, so I am trying to get one coil that will do me the best job for old home sites for older coins. Anybody that has used these coils I would appreciate your input.

 

[rwsnc]

Don't know if this will help you much but, I just got back from doing a little detecting. Amongst other things, I found a SS ring that rang in at a solid 40 on my XT70. I was using a 5x10" elliptical DD coil. I'm mainly interested in silver coins and jewelry and use the 5x10 almost all the time.

 

[Digger]

If the soil you are hunting in warrants using a DD coil, then I would suggest the 10-inch DD at 7.5 kHz. However, if your soil is moderately mineralized, you should do well with the stock 9-inch concentric at 7.5 kHz. Personally, I like the 9-inch concentric at 3 kHz. Granted, it doesn't achieve more depth than the stock coil. But around old rural homesites, I believe the deeply buried iron gives me a more distinct audio report. If they are urban homesites, littered with lots of modern trash, you might require the greater separation characteristics of a 6-inch coil. Whether you would do better with the DD or the concentric will again depend on your mineralization. I don't know of any magic formula for determining when a DD coil will perform better. However I go by the numbers represented when I ground balance. If I properly GB my concentric stock coil, and the numeric display indicates a 28 or more, I feel confident using my concentric coils. If the number is smaller than a 28, I usually switch to a DD coil. JMHO HH Randy

 

[Jackpine Savage]

Although its primarily a deep silver coil, with the sensitivity set around 16 or so it will do great in iron. Just pretend its a small coil, go slow and overlap the heck out of your sweeps. Pretend you are painting the ground with the open center part of the coil. I was amazed at what it would do against other machine/coil combos at some worked out sites.

Tom

 

[RonNH]

The 6" coils may lose some depth, but around iron infested home sites, I think target separation is more important than depth. In fact, I can run my 6" HF coil a little hotter (more sensitivity) than I can the 10.5" so it may even get the same depth. The 6" will see less of the ground, so it might pick up that Seated dime that is between two rusty nails where the 9 or 10.5 would see all three at once and may give a low iron signal. Ron