Large silver or high conductor

[autopilot42]

All of this going on with the new gold bug has got alot of testing going on my part and others. I have noticed that my F5 does the same thing as the gold bug with large silver one troy once commerative coin and in disc mode they will not pick it up well. It seems to me the machines are having a retune problem on large silver. My gold bug does have a problem with depth and ground balance as it is 20 points off from my F5. The problem with the F5 is not as severe as the gold bug as we saw in jessgo 33 video but it still exists. When in all metal both machine are fine except for the depth on the gold bug which I am sure can be corrected when I send it in. I tried changing the ground balance setting on the F5 and the gold bug but it seems to make no difference with large silver. Also I tried to different coils on the F5 one being DD the other concentric which make no difference. The only machine I have that can pick up the big silver consistently is the F2 it doesn't mis a beat. Is this typical of all the mid range and higher performance Fisher or is it just me. Or is it the way the disc circuits and software are designed. Is this because you are at the top of the range of the disc circiuts performance.

Any insight is appreciated

Bob

 

[Mike Hillis]

Bob,
What you are discovering in your testing isn't unusual for the F5 or most any of the other make and models of metal detectors. Its called "wrap around".

Most of the time you experience it from the other direction, the ferrous to the high conductor wrap around, where oxidized iron will false or read as a high conductor. I'm sure you are already familiar with this as it is a common phenomenon.

With the very high conductor target, you are experiencing the wrap around in the other direction, from high conductor to ferrous. Using the F5 as the example, once you have exceeded the limits of the high conductive range, the high conductive target will read as an iron object. If you lower your disc setting to minimum you can easily see this. Your very high conductive silver target will read in the 14 to 15 id number range with a repeatable iron tone. Just the nature of the beast due to the design characteristics.

My Whites V3i does the same thing. Throw in some hot dirt and it gets even more interesting

The same thing is happening with the Gold bug. Due to the issue that some are having with a mis-adjusted ferrous ground balance range setting, it is just more pronounced than it would normally be.

Hope that helps,
Mike

 

[autopilot42]

Mike thank you very much. The reason why I posted this was to have someone explain this because it was happening with my other detector which works fine and have never had a problem. In the end this will be a good learning experience and eye opener for myself and other folks who are new or not as experienced as others. Again Mike your expertise and patience is always appreciated.

Take care
Bob