M6 Ground Balance

[KurtB]

Do you have to turn the machine off and then on again to reground balance the detector or can you just find a clean spot and pump the coil in auto trac? Sure wish Whites would have let you see what the GB was set at after bobbing the coil, oh well. Thanks

Kurt

 

[cosmic]

Just pump it in autotrac.. I like to lock mine after since my ground doesn't vary much..

 

[Rob (IL)]

No you don't have to turn it off. Actually the M6 is always GBing and adjusting. It is even tracking the ground when you have the Trac locked. The ground balance is not changing with the ground but it is tracking and if you unlock it it will immediately update the GB. Rob

 

[Monte]

Do you have to turn the machine off and then on again to reground balance the detector or can you just find a clean spot and pump the coil in auto trac? Sure wish Whites would have let you see what the GB was set at after bobbing the coil, oh well. ThanksKurt

[size=large]Once you know the strengths of the Auto-Trac circuitry as used in the MXT, you can live w/o the Ground Phase reading. Yes, I, too, would like to see it on the M6, but knowing how the auto-tracking works, I can easily live w/o it.

No, you do not have to turn the detector off. You do have to remember that, once you turn it off, you'll have to re-balance when you turn it on again.

When you turn the detector on you can just leave the tracking toggle in the rear position and let the Auto-Trac circuitry take care of things. The auto tracking works very fast on the MXT & M6 and, after just a few sweeps as you start searching, the circuitry will quickly establish a Ground Balance.

While searching it will maintain an operating Ground Balance as it is constantly reading and analyzing the ground mineral changes and will update the GB setting as needed. If the ground mineral is rather uniform or slow-changing in an area, leaving the toggle in the preset Auto-Trac position works well. If you're hunting a small area with rapidly-changing ground mineral, often apparent visibly, and/or there is an abundance of small iron-based trash, it will often be to your benefit to establish a good working GB over some of the more mineralized ground present, then toggle to the center Lock setting. This will lock or hold the GB that was established. I've been working a renovation site where they have scraped off the top 1"-5" of sod and dirt exposing old dirt and rock and many iron nails from when the old school was destroyed. Rock are also present, and there is a distinct difference between some of the upper 3" of dirt and that below. I set the GB so it's just 'On' over the worst ground and that means just slightly positive over most of the dirt, then I lock that setting.

All searches are done in the motion Discriminate mode and that's the mode that has a functioning Auto-Trac working for you. You can bob the coil over a bare patch of dirt in the Disc. mode, and it only takes a few 'bobs', or you can sweep the coil over an area that's target-free. Do this in the tracking setting and then, after a few sweeps or bobs of the coil, hold it about 6"-8" high, trigger toggle into the All Metal Pinpoint mode and lower the coil towards the ground.

If the threshold audio stays relatively unchaged, you're good to go and can search with tracking or toggle to lock to hold that GB. If lowering the search coil results in a slight audio increase as the coil nears the ground, it is just slightly positive and (that's how I usually like it in challenging sites) you can lock it or just search and let tracking work for you. If the audio nulls out when the coil is lowered, that's a negative GB and you don't want that as you'll be prone to false signals. Find a different spot and re-balance (bobbing method).

As someone else pointed out, the M6, like the MXT, is continuously reading and analyzing the ground mineral and if you're in the preset tracking position it will monitor ground changes and maintain or adjust the GB to the updated info. If, however, you're searching in the 'Locked' GB setting, the Auto-Trac circuitry is still working during the search to read and monitor ground mineral changes. If you are searching in a Lock setting and want to 'update' the GB setting, all you need to do is stop sweeping the coil and hold it still, toggle to the tracking position and then toggle back to 'Lock'. That should update the GB setting to that which the circuitry has been reading during the last sweeps.

Keep in mind, too, that the Auto-Trac works in the motion Disc. mode and triggering into the All Metal Pinpoint setting disables the tracking. The one this this right-hander wished White's would have done is put that toggle on the other side of the housing so it was easier to see and get to. What I usually do, when I am bobbing the coil or sweeping in order to establish a working GB and then plan to toggle into the Lock position, once I feel the GB is right (and I know this because I lower the coil from 6" or 8": in the All Metal Pinpoint mode toward the ground), I keep the trigger in the Pinpoint mode while I lift and twist the detector to reach over with my left hand and toggle into Lock. That way, my coil lifting and movement by the ground won't alter the established GB.

Enjoy the search! The M6 is terrific for most applications. If you have any questions you feel I might be able to help with, ask away or drop me an E-mail: MonteVB@comcast.net

Monte[/size]