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View Full Version : Purposely GB The V3i Over Non Clean Ground, Balance Still Good!



MartinL
11-13-2011, 03:28 PM
I decided just a while ago to test my V3i for the feature of Auto Balance, so I first thought that I would need to de-balance it. Well, I first balanced it over my buried 5 quarter, then went to the clean spot I knew about close by to see how much of it was. Mind you now, the Auto feature was OFF, LockTrack ON. The first lower of the coil with the trigger and menu button depressed, like you do for pumping the coil for GBing, showed a perfect balance, arrows switching without any pumps. So, still in Lock Track, using the GB I actually did over THAT VERY TARGET. I swept the 4 quarter again, it read as well as always when using the 6x10DD coil. I proceeded to test the 8 quarter I had buried close by, and it hit as good as good gets for the 6x10DD. So I went insane and went looking for ultra junky ground to balance over, and I'll be danged if I could ever make the V3i NOT get a good ground balance. I couldn't make the V3i fail getting a good GB. Again, my conditions were:(and this test began in a venture to test the Auto Track precision, not just being a trouble maker)

Lock Track engaged
6x10&quot:grin:cheesysmile:
C&J(tweaked a bit)
Balanced right over buried treasure
Also balanced misc -Vdi junk
Tested for finding a 5 and an 8 buried quarter
Tested GB over known clean ground

As an extreme, I even tried balancing over a surface coin, but of course it never quietened completely during pumps, so I took the best it offered, and it STILL passsed.

It passed without having to scrutinizing the cleanliness of the ground in every situation, at least with every target I had buried in the garden. In fact, if anything, I got better results, which I know has to be nonsense. What am I missing here?

Unless I am missing something, and I may be...all this hype of ground balancing over clean ground being an absolute must, is an extreme overture. martin

Ytcoinshooter
11-13-2011, 09:10 PM
Interesting post Martin. One thing I would suggest is to check the GB just raise the coil off the ground - pointing outward, raising it almost waist high, only pull and hold the trigger and lower to the ground. Does the threshold increase or decrease....? Stays the same? I suspect that by holding the touchpad and pulling the trigger as you did it begins the GB sequence again. The holding of the coil straight out, triggering and lowering coil to the ground has long been the way to check the GB on Whites. I can't account for the results you got. The test bed is a great tool, keep experimenting but get some sweeps over the ground before checking the GB. I'd be interested in your findings. :groovy:

CyberSage
11-14-2011, 08:28 AM
Martin,
You want to choose clean ground balance because your teaching the machine to ignore ground mineralization. Even with weak targets present the V3/V3i will ground balance sometimes however. While the detector may seem to have a proper GB you will find that your frequency responses in the pinpoint screen will be skewed on deeper targets. For me, having a good GB is critical for this reason.

Jack

MartinL
11-14-2011, 02:10 PM
All I know, is that I can't purposely unbalance the 6x10DD to make it completely fail seeing my 8self buried quarter. I didn't remember I had that 8 quarter there until I discovered it with the stock 10 D2 a while back, so I've benchmarked the tweaks on the V3i with that target. To me, an 8 detection with the 6x10DD is good work to begin with, and then stack on the fact that I've never been able to corrupt a GB over junk ground conditions so it WONT detect it. Is there a full proof way to de-balance the V3i to accomplish that Jack? I can certainly reduce settings such as TX, etc., but how would I corrupt the GB in a variation of the standard GB routine?

martin

MartinL
11-14-2011, 02:25 PM
Interesting post Martin. One thing I would suggest is to check the GB just raise the coil off the ground - pointing outward, raising it almost waist high, only pull and hold the trigger and lower to the ground. Does the threshold increase or decrease....? Stays the same? I suspect that by holding the touchpad and pulling the trigger as you did it begins the GB sequence again. The holding of the coil straight out, triggering and lowering coil to the ground has long been the way to check the GB on Whites. I can't account for the results you got. The test bed is a great tool, keep experimenting but get some sweeps over the ground before checking the GB. I'd be interested in your findings. :groovy:


I went back out again where the 5 and 8 coins are buried, which in near the clean ground I've used to GB for over a year while testing. To clarify one thing you eluded to...I was not pulling the trigger and pushing the menu button to verify my balances, only pulled the trigger while lowering the coil toward the ground. I repeated it all again just now, first by using the clean spot. Raised the coil after getting a quiet tone in GB, trigering and slowly lowering it to the ground, and the tone had a quied middle part, and slightly elevated right at the ground surface. Tested the 5 & 8 targets, both hit, the 8 needing a bit more of scrutiny in the waggle.

So I went to test #2, went to the edge of my circle drive where I get a lot of hum from the reinforcement in the concrete(figured that to be about the worst case GB spot) and GB-d again, and I even got a quiet tone during the GB. Raised the coil, pulled only the trigger as I did in the clean spot, and the noise ramped up due to the reinforcement in the cement. So, I took the machine to the clean spot, raised the coil, triggered only, not with menu, lowered the coil, and I got a quiet tone during the last 75% of the lowering range, never to recover at ground surface level like the trashy balance verify did. .

I went to the 5 & 8 coins again, and I may be fooling myself, but I am going to state that the 8 buried coin picked up better with the GB over the sour spot. I simply can not make a bad balance, and like I said in my post to Jack, that 8 coin used to be invisable to be for a while, only to be seen with the 10&quot:grin:2.

If you have a coin garden, maybe you will test your V3i and 6x10&quot:grin:cheesysmile: to try the same measurements. All of this perplexes me, but at the same time, it will certainly speed up my GBs if I can just do a random GB everywhere I wish, and still get 7-8 with a 6x10 coil. I can live with that. I am still gonna mess with this today to try and see if I can get a bad balance.

As a reminder to all, I am running in LockTrack in all of these tests. martin

So I ran test #3. I GB-d over a buried nickel at 4. It struggled for a quiet tone during GB, so it wasn't perfect when I called it good enough. I went back to my 5 & 8 coins again, and I am sure that the machine and coil, with the GB over a buried nickel, not a clean spot, hits the 8 coin better than with a clean-ground balance. I have yet to see a downside to all this yet. I hope someone else runs a quick test themselves.

One downside I noticed is that the pinpoint sound goes null on a not clean ground balance, but at the same time, target signal on the 8 coin in search mode with a clean gnd GB. IMO, I'd rather have the search tone say there's a target down there deep, and then trust the digital display. w/o sound. I'll add another twist also. Test #4: I have a pull tab buried at 3. I got to thinking that maybe since the nickel improved the signal response of the deeper quarter, that the aluminum tab may be better. It appears so far that the usage of the PT for GB certainly is better than with the GB over the nickel. Granted the 8 quarter puts the signal tone in search right on the edge of non detection, which is indicated by very broken tones when using the GB over clean ground...sometimes shows nothing of interest, yet the pinpoint shows it is there.

So, I am still of the frame of mind that the intense search for extremely clean ground in not imperative. I'll add that if you do a GB over any old area of ground, and then go to a clean spot to do another balance...it will balance in mere seconds. I even began lowering the coil to the ground surface with only one movement with the menu and trigger engaged, watched the arrows until it switched, and that was a good GB when verified for me when doing a fresh GB on the fly. You get a balance right to the ground itself too.

OK, I have had to stress some peeps here with all this experimentation, but isn't that what the gurus keep promoting? We are after all, White's guinea pigs in a way.

Martin

Ytcoinshooter
11-14-2011, 05:01 PM
Martin, I don't know what to make of your results. I know that with the limited time I have in my new V, trying both auto track and lock trac I've seen the GB drift out of balance with AT. Also the ground change to where LT was then off. This was in a ploughed farm field. Our soil strengths may differ and/or possible filter used? Filter choices may enable a wider acceptance of signals that come trough...? Maybe the detector is sensitive enough where it will still sing out on round, good conductive targets? I need more time with the V to offer anything meaningful. I have lots of experience with the XLT & DFX to know I was rarely out of GB. Really though, I do appreciate your testing.

MartinL
11-14-2011, 05:14 PM
Thanks. I appreciate your interest. I'll betcha there's some here maybe saying to themselves, What's this nut doing all this for? It may have answered some of my early woes concerning no audio in PP mode. Oh well, it gave me something to do. martin

CyberSage
11-14-2011, 07:33 PM
Your missing the point Martin. Sure it will detect the quarters and remain relatively quiet on a pump test, but on a deep coin target it will skew the frequency response, meaning that the 22.5Hz will show 2nd dominance instead of the 7.5hz or 2.5Hz. (Copper, Silver) A quarter is a big target. Try a dime at 7 or 8 inches. A good clean ground balance is imperative to proper detector response.

MartinL
11-14-2011, 09:27 PM
I will try a dime, or a penny, but probably not at 7-8 with the 6x10DD coil...it will never get that deep, never has here yet anyway. The 10 will though, and it's on the machine now anyway. I admit that I didn't take any notice of the freq dominance, just noticed that the search tone on that 8 quarter was more consistent than with the clean ground GB. Vdi numbers seemed a tad higher, but not much. I'll see what the 10 D2 does on an 8 buried dime though. Do you expect that to be a valid situation to make your point? martin

Dimeman
11-14-2011, 10:37 PM
If you ground balance over any metal item, the detector will balance at a reduced depth due to the metal interference.


On some of the older detectors you could tape a penny to the coil and the SAT ( self adjusting threshold) would compinsate and adjust the penny out so it would not sound off. When you passed the coil over another penny you wouldn't hear a thing--it was cancelled out--it was like a ground balance.


I had a Whites M6 from Jan 2007 until Feb this year. Good ground balancing over a clean spot of ground, the M6 with a 6X10 inch coil could detect with no problem, a dime at 8 inches--all day long...........and I'm also in Texas's soil down here in Houston.......... If the M6 can do that, the V3i should be able to get more depth due to the better computerized workings in it.

Why does every detector manufacturer tell you to find a clean spot of ground to do a ground balance:huh: :thinkingabout:

earthmansurfer
11-15-2011, 02:56 AM
Martin, one thing I have noticed with the V3i from hunting in ground with lots of iron. If I GB in an area that is not clean, I am asking for problems. I haven't done this on purpose but rather have had such a hard time finding a clean area to ground balance and would accidently GB to some iron and without fail the detector got chattery and lost depth. I run autotrack when the ground gets so bad I can't find a place to GB.

I think what you may be experiencing is that the engineers must have built in some fail safe methods not to GB to ground (or rather a target) that is off by so much of a % to the majority of ground. Sort of like how you can set auto track to inhibit and not track to ground.

When your GB is off even a little (as Jack said) it skews the frequency response. It takes away from the detectors ability to see into and around trash/iron. The detector gets a lot of it's depth from it's sensitivity and not raw horsepower per say. I have found when the GB is off, this is sometimes severely affected. I have noticed this (and read the same) with any detector I have ever used. Sometimes the depth or performance is barely noticeable but other times when the conditions are tough, you see it quite clearly.

EMS

MartinL
11-15-2011, 03:30 AM
All I know is that I can intentionally GB directly over a buried pulltab at 3, sweep for my 8 quarter, and get better pickup and tonal reply then when I GB over clean ground. Same thing if I GB over a buried nickel. I am kinda simple minded I 'spose, but that seems like an improvement, or at least a worthy note. EM, you mentioned auto track in iron infested ground. What happens to the on-going GB during sweeps if it triggers then when you happen to be over some of the iron. Statistics says that'll happen, and Murphy's Law says it's more than likely. What prevents errors there? Isn't the V3i balancing with cruddy data points at least intermittently?

I'm probably going to use the quick GB over any old ground first just to get the clean GB done faster, and for experiments. Besides, I've learned that the 10 coil hardly shows the same mystery, if any at all, but I've not buried anything over 8 yet to push it's limits. I still need to view the frequency skew with the 6x10 and the dirty ground balance as well. Overall, it still trips me out that I can IMPROVE the basic pickup of response on that one 8 coin when using non clean ground over clean ground. I dig just about all positive VDI numbers anyway, so why wouldn't I like to get tone better on my threshold depth target(my 8 coin is that today with the 6x10) than with a clean ground GB? My momma made me a tad stubborn, her being from Missouri and all :behave: martin

earthmansurfer
11-15-2011, 12:22 PM
Martin, what you are experiencing is not exactly a mystery (in your defense!). I have heard of ground balancing over iron to negate it. This theoretically can work but if the ground (iron) changes at all your GB point will be off and masking will be worse! I mean you also could tape a penny to your coil (at least with the older detectors) and it would be a crude form of discrimination and you would avoid pennies!

Understand what GB'ing does. It negates the ground's signal at its most basic level. Think about that as you GB. So, as you read the following, think about what you found out and what I am saying. I do find it interesting to a degree to think about this.

Now, you can GB over a pull tab and theoretically get the same result, but again, this is a big if and even if it worked if conditions change things will vary. Now, you may pick up your test coin even better, but what you are seeing I believe is a GB point that is just making the coin more sensitive. The correct way to achieve that is to run your GB pos (with the offset) I believe. Play with this, compare it to your stumbled upon method. I mean, you may be on to something, but I really think it's just what I have described.

What you have stumbled upon warrants further testing but NOT by GB'ing against pulltabs and the like (only). Play with running your GB + or -. Now you are on to learning your machine, really. And this will translate to other machines as well (though the scale on the V3i is sort of relative to the ground you are at it seems.)

Regarding auto tracking in iron, the detector has some very sophisticated algorithms to avoid GB'ing to the ground. Trust me, it is much more complicated than GB'ing against a pulltab >:tongue: (Sorry, couldn't resist). eheheh
What I was saying regarding this and what you said before is that I think White's might have incorporated some of this inhibit function into locktrack so as to avoid GB directly do an object that is clearly so far away from the VDI of the ground. (Just to protect the end user).

Hope that helped,
Albert

MartinL
11-16-2011, 01:42 PM
I can GB over my buried coins and still still get them in an active search. martin

CyberSage
11-16-2011, 02:05 PM
I can GB over my buried coins and still still get them in an active search. martin


Yes, this is to be expected, but you then have a skewed ground mineralization for your GB. As stated this will alter 3 frequency response adversely in pinpoint mode, and probably rob you of some sensitivity. Ground balance becomes more important as the targets get deeper.

Ytcoinshooter
11-16-2011, 03:42 PM
I'd like to ask something or at least put this out there. My DFX & XLT while in autotrac seldomly were off. Subsequently rebalancing they kept an accurate GB longer than what I have so far experienced with my V3i. It seems I move along detecting a few feet after re GB and it's off again. Is it that the V is way more sensitive? Granted my time on the new unit has been limited but I'm very aware how important a correct GB is to maintain. My first whites in 1986 was the 6000 Di Pro and the AT was hailed as a big deal. Kinda wish I still had now with my hunting experience to try a few things with it. I've had Fisher units all with manual GB and they were seldom off GB. I still have a CZ20 w10 coil and it goes deep. It's just not my first choice for casual hunting. Salt beach sand, fresh water, sloppy mud in the rain and any foul nasty weather it's a go to unit. I don't run that thing on the shaft out of water though...heavy detector.
Sure I'd like to read into Martin's that maybe I'll be fine in the first 6 inches with my V even if the GB has drifted. Next time I think I have a deep target I will check the GB. Re GB if off and check the response again. I gotta get my coin plot planted soon.

earthmansurfer
11-16-2011, 03:57 PM
Coinshooter - How do you know your GB is off? (Is is falsing more or ?) I ask because I wonder if I am missing something. I run autotrack with it at 10 (so it doesn't check that often) and I do see the arrow moving to correct the GB every so often, but not that often. With my Omega it is easy to see when it's off as it shows you so quite clearly but on the V3i?

I've heard people say the V's autotrack is the best of all of White's machines and at the same time I've seen very experienced hunters say it isn't that good or at least that they prefer locktrack.

I sometimes do a manual GB while in autotrack and it never has to adjust it much if at all (and my ground is like yours if I remember those numbers correctly.)

Thanks,
EMS

Ytcoinshooter
11-16-2011, 04:28 PM
Hey earthmansurfer! No falsing I can tell. To check I lift the coil off 3 feet approximate waist high, holding it out like this ---/ then I hold the trigger in, slowly lower it to the ground in the normal (coil flat) fashion and listen. The threshold should be steady, not increase or drop-null out. Nulling is would be kinda like a negative offset (but I can't tell how much it is jus by that, an increase in threshold is the unit seeing the ground as positive - but again - how much it is off I don't know. I always make sure im not over metal if it goes +. So I do the GB again. I'd like Martin to try checking his GB after 1) balancing over metal, 2) after balancing normally -as in a clean area. Then after sweeping - searching for a while. It would be interesting to see if he is going + or minus after sweeping for a while or is it correcting? Recheck his planted targets. It's easier to do than explain :rolleyes:

rcsnake
11-16-2011, 08:33 PM
To tell if the instrument is properly ground balance can be accomplished by raising the loop to waist level and then pulling the trigger to put the instrument into the pinpoint mode. Then lower the loop to the ground (while holding the pinpoint trigger in) and listening for no change or little change in the threshold. If the threshold increases in sound as the loop is lowered, then this would be known as a positive ground balance or the unit may be out of ground balance balanced. This is the same method described in the above post by Ytcoinshooter.

Then I also set the loop on the ground in the search mode and then put the instrument into the pinpoint mode. Then raise the loop to the waist level (while holding the pinpoint trigger in) and listening for no change or little change in the threshold. If the threshold increases in sound as the loop is raised, then this would be known as a negative ground balance or the unit may be out of ground balance balanced.

If the instrument is out of ground balance it may get chatter exhibit + 95 vdi readings and as pointed out early the vdi may be skewed.

I usually hunt in stereo mix mode any more and I can tell easily if the instrument is out of ground balance by raising the coil a little at very end of my swing and by accepting all vdi in the disc mode if out of balance i usually get lots of vdi numbers in the ground range.

OK, I rambled enough so I will end this blurb as most of you probably already know this. HH

rcsnake

Ytcoinshooter
11-16-2011, 09:38 PM
Thanks rcsnake, I forgot about checking in reverse. I'd bet that if Martin does a GB over a target it will always be off because the initial reference point was doing the GB was off. I'd be amazed if it tracked to correction or a correct GB. The thing that interests me is that the V is sensitive enough to still hit on his 8 coin.

CyberSage
11-16-2011, 10:52 PM
Thank you Bob! Your input is greatly appreciated here on the forum, as always.

earthmansurfer
11-17-2011, 02:35 AM
Thanks coinshooter and RCSnake for the input. I sometimes do the first method (oops forgot about that) and I can say NOT ONCE has my GB been off in that way. I admit I have to do it more often but I had been doing it 2 or more times or so a hunt up until a few hunts ago with perfect results. Guess with it always having a good GB I have been spacing it lately.

I'll start doing it more often!

Coinshooter - The strange thing with Martin's GB test is that he picked up the coin better at 8! That is why I thought he must have essentially had his GB + offset enough to make it more sensitive to the coin. I thought then comparing it to a regular offset would have proven this...

Thx,
EMS

rcsnake
11-17-2011, 11:45 AM
Ground balancing over a target will pull the ground balance point if the target strength and phase reading from target combined with the phase and target strength from the ground signal still falls within ground range of the instrument. If the combined resultant of these two targets is out of this range the instrument will not track to the target. If the instrument does balance then the effect would be like applying an offset to the ground balance point and this offset may increase target depth on some targets.

This range can be extended by using either the salt mode under frequency or by using the salt setting under Tracking/soil. By doing this it is possible to ground balance over a nail but not targets like a quarter unless the quarter is having an effect that would apply to the above paragraph.

The ground balancing of the instrument is really critical to in mineralized ground to achieve the best depth. With that being said if the ground is so weak then the ground balance point is not that critical but to get the most out of the instrument it is best to ground balance the instrument. Or at least this is my opinion on this subject. HH

rcsnake