VoyForums
[ Show ]
Support VoyForums
[ Shrink ]
VoyForums Announcement: Programming and providing support for this service has been a labor of love since 1997. We are one of the few services online who values our users' privacy, and have never sold your information. We have even fought hard to defend your privacy in legal cases; however, we've done it with almost no financial support -- paying out of pocket to continue providing the service. Due to the issues imposed on us by advertisers, we also stopped hosting most ads on the forums many years ago. We hope you appreciate our efforts.

Show your support by donating any amount. (Note: We are still technically a for-profit company, so your contribution is not tax-deductible.) PayPal Acct: Feedback:

Donate to VoyForums (PayPal):

[ Login ] [ Contact Forum Admin ] [ Main index ] [ Post a new message ] [ Search | Check update time | Archives: 1, 2, 3, 4, 5, [6], 7, 8, 9 ]

[ Next Thread | Previous Thread | Next Message | Previous Message ]

Date Posted: 11:32:14 07/07/02 Sun
Author: Ralph
Subject: The Problem......
In reply to: jim straight 's message, ""Hot Rock" controversy: Some authorities claim sometimes they cannot be groundbalanced out---" on 00:32:54 07/07/02 Sun

.....isn't so much in balancing out individual rocks, but the wide variations that may occur from one rock to the next. This may not be as big a problem for auto-tracking machines, but with a manual machine, you simply cannot "balance to" every positive rock you encounter to exclude it from being a "good" target. Because of their effect on any manual machine, so-called "negative" rocks take care of themselves by their signature "null-boing" reaction. But with auto tracking units, and dealing with very small or very deep pieces with only the slightest target signal to begin with, "masking" of those faint signals either caused by positive OR negative rocks or iron junk (if you try to nuggetshoot in discrimination mode) can very easily become a problem. Changes in the ground mineralization can just as well, and is one of the reasons that most serious nugget hunters prefer good manual machines over "auto-trackers" when it gets right down to top performance. With a good manual machine, you can keep track of what the ground is doing beneith the coil. With an auto-track machine, you may never know when conditions have changed.

I've seen very few true "hot-rocks" that could not be balanced out on an individual basis, unless there were true metallics of some kind within the rock. The hardest are the highly magnetic volcanics, usually red maghemite. I've seen areas where the "matrix" was basically made up of red volcanic dirt and rock, where you balanced to them rather than the constituent background. There was just no other way to hunt in the stuff. You just listened for good "ZIP" signals amongst all the other noise, and it gets to be a real pain....... but worth the effort in some instances.

But, again, you can usually ignore negative rocks from the outset because of their signal reaction. That can eliminate a good half or more such "hot-rocks" in some areas. The positive rocks are the only ones that really have to be dealt with as far as distinguishing them from good target signals. In the majority of cases, nothing more is needed than a little trick called "shift-balancing", where you offset your ground balance point slightly on the negative side in order to "zero" the positive response of the rock. If you have to shift very far, better check that rock ! It ususally takes only very little shift to zero a non-metallic hot rock, while true metallics are almost impossible to "balance out" on a good quality machine.

Good bunch of posts lately Jim ! Looks like you have everyone on their toes.... (grin)

Ralph

[ Next Thread | Previous Thread | Next Message | Previous Message ]

Replies:

  • Re: "Hot Rock" controversy: More: By their definition---?? -- jim straight, 12:12:12 07/07/02 Sun
  • Sure, you can balance the machine to the rock........ BUT -- Ralph, 16:40:23 07/07/02 Sun
    [ Contact Forum Admin ]

    Forum timezone: GMT-6
    VF Version: 3.00b, ConfDB:
    Before posting please read our privacy policy.
    VoyForums(tm) is a Free Service from Voyager Info-Systems.
    Copyright © 1998-2019 Voyager Info-Systems. All Rights Reserved.