Ground balance & VDI/TID #'s

[KSDfisher77]

I recently acquired a new Minelab Xterra Pro & i am fairly new to it & it's my 1st Minelab detector. My question is does ground balance affect your VDI/TID #'s? I do a auto ground balance when I 1st start & about every 20-30 during the hunt.
Today while hunting I dug a few modern coins with good VDI/TID #'s & tones. What has got me stumped a bit, is I dug numerous can slaw scraps which had a good clad dime VDI/TID #'s & tones. Actually dug more than I would like to admit. Was it just dumb luck/ coincident that the can slaw was ID'ing as coin VDI/TID #'s Thanks.

 

[thepest]

I was experiencing the same thing the other day... small bits of aluminum cans about the size of a half dollar.... and carona caps... they are the worst... they read slightly different than any other kinda pop top for some reason... hecho en mexico I guess...

 

[KSDfisher77]

I was experiencing the same thing the other day... small bits of aluminum cans about the size of a half dollar.... and carona caps... they are the worst... they read slightly different than any other kinda pop top for some reason... hecho en mexico I guess...
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Yeah I'm unsure if it's the soil in this 1 particular spot or what. It's always been tough/rough hunting. I thought I had a pretty good handle on the Xterra Pro, cause usually if I turned 90°degrees on the coin target/can slaw I could tell if it was junk or not by the small change in the VDI/TID #'s. But that was not the case today, i got bobby dazzled numerous times. I was ground balancing over clean ground & my ground balance #'s did not vary much thru numerous ground balances. I've read the lower the ground balance # the better, for whatever unknown reasons. We recently got about 3" of rain & idk if that was throwing me off or what either. Lmao it's like this detector got a mind of it's own. It's been a coin magnet for me. But there are days it's a can slaw slayer!!!

 

[thepest]

You may be onto some thing with the 3" of rain.... Is it too much moisture... or not enough.... the weather is so screwy any more.... it went from almost flooding to bone dry here... like some one flipped a switch....

 

[KSDfisher77]

You may be onto some thing with the 3" of rain.... Is it too much moisture... or not enough.... the weather is so screwy any more.... it went from almost flooding to bone dry here... like some one flipped a switch....

Yeah we went from bone dry to soaking wet in a matter of a couple days. The days I did find the most coinage were on dry days, but I was also in a park. Usually the wet ground will help detect/find deeper coins better, I think that is due to the Halo effect. Maybe the salt content from ground being wet was throwing me off or maybe was affecting detector performance. I'm new to Minelab, but not to detecting.. Lol sure looked like I was new to the hobby today!!!

 

[vlad]

I recently acquired a new Minelab Xterra Pro & i am fairly new to it & it's my 1st Minelab detector. My question is does ground balance affect your VDI/TID #'s? I do a auto ground balance when I 1st start & about every 20-30 during the hunt.
Today while hunting I dug a few modern coins with good VDI/TID #'s & tones. What has got me stumped a bit, is I dug numerous can slaw scraps which had a good clad dime VDI/TID #'s & tones. Actually dug more than I would like to admit. Was it just dumb luck/ coincident that the can slaw was ID'ing as coin VDI/TID #'s Thanks.

GB and the ground mineral both affect the i.d., there was no trash targets registering under the slaw or at loop's edge?

 

[KSDfisher77]

GB and the ground mineral both affect the i.d., there was no trash targets registering under the slaw or at loop's edge?

After retrieving the can slaw target it would be clean in that area, nothing showing again with the metal detector. I will say the can slaw targets that were hitting as coins was deeper than normal, so to say. Maybe I needed to speed my recovery speed up, to compensate for the ground minerals due to the ground being wet. I hunt with a slight threshold, & if I notice a change in my threshold, I would re-ground balance. Thanks Maybe I just need more time behind the wheel of this new detector too. I will also mention I've been using the EQX06 6" equinox coil on my Xterra Pro.

 

[vlad]

After retrieving the can slaw target it would be clean in that area, nothing showing again with the metal detector. I will say the can slaw targets that were hitting as coins was deeper than normal, so to say. Maybe I needed to speed my recovery speed up, to compensate for the ground minerals due to the ground being wet. I hunt with a slight threshold, & if I notice a change in my threshold, I would re-ground balance. Thanks Maybe I just need more time behind the wheel of this new detector too. I will also mention I've been using the EQX06 6" equinox coil on my Xterra Pro.

Learning a new machine takes time but deep slaw usually reads nickel to tab: let us know what happens and try different frequencies. Try a different loop too.

 

[thepest]

Learning a new machine takes time but deep slaw usually reads nickel to tab: let us know what happens and try different frequencies. Try a different loop too.

Last time out with the same setup as KSDfisher77.... I did find 2 nickels.... I had thought there weren't any more coins to find in that lot.... while challenging to figure out... this detector is proving to be exceptional....

 

[IDXMonster]

GB WILL affect VDI, whether it’s negative or positive. If GB is way off to the negative you’ll see unstable operation, off to the positive it’ll be very stable but you’ll lose depth(typically). A very negative GB is what usually causes erratic/inaccurate VDI. This has applied to the machines I’ve used anyway.

 

[KSDfisher77]

GB WILL affect VDI, whether it’s negative or positive. If GB is way off to the negative you’ll see unstable operation, off to the positive it’ll be very stable but you’ll lose depth(typically). A very negative GB is what usually causes erratic/inaccurate VDI. This has applied to the machines I’ve used anyway.

The day I was hunting, the ground was real wet from recent rains. I was using the new Xterra Pro & my ground balance showed a -6 to +6 thru out my hunt. Also the can slaw that hit as dimes, I will mention were more of a ball of can slaw & roughly the size of a dime to quarter size. The Xterra Pro really is a exceptional machine for $269, it's almost paid for with the newer clad I've dug. Also I dont expect It to discriminate/I'd as well as the higher price units. Thanks.

 

[KSDfisher77]

I guess now my question is, how does the ground balance affect the VDI/TID #'s. Does a negative ground balance # bring the coin/target VDI/TID # down? Does a positive ground balance # bring the coin/target VDI/TDI # up? What are the effects of target VDI/TID #'s versus the ground balance #'s? Lol I guess this is what I'm trying to ask. Thanks.

 

[KSDfisher77]

Would a high positive ground balance # cause a silver half dollar to wrap around the VDI/TID scale to a negative VDI/TID # of a ferrous iron target. Due to the wrap around effect. Thanks.

 

[IDXMonster]

I guess now my question is, how does the ground balance affect the VDI/TID #'s. Does a negative ground balance # bring the coin/target VDI/TID # down? Does a positive ground balance # bring the coin/target VDI/TDI # up? What are the effects of target VDI/TID #'s versus the ground balance #'s? Lol I guess this is what I'm trying to ask. Thanks.

Typically a positive GB makes things more stable and the VDI is accurate. A very negative GB makes the VDI jumpier/not as stable. I haven't seen it CHANGE the actual VDI in either case, but I haven’t tested it specifically at length….just observations. Using different FREQUENCIES can change the VDI somewhat depending on the machine, but not to the extreme extent of wraparound.

 

[vlad]

Would a high positive ground balance # cause a silver half dollar to wrap around the VDI/TID scale to a negative VDI/TID # of a ferrous iron target. Due to the wrap around effect. Thanks.

The ground balance will move the tid up or down slightly. I can hold my Mk-1 toggle left and move the ground and watch the needle move in the same direction as the ground knob is turned. Remember, the ground adjust control is just another form of a discrimination control. Its used for discriminating out the ground. A VLF detector stat mode by its very nature is only designed to respond to the target signal and ignore the ground signal. Since the ground reaction primarily produces a signal in the receive coil the VLF detector does not pick-up the ground but only responds to the signal of the target. Therefore, the VLF detector only needs the target signal for proper operation. However, for discrimination we need to measure the target signal and add the ground signal to determine what the target is. Since we are using the ground signal then we have to contend with the resultant ground signal pick-up, and all grounds have varying amounts of magnetic and conductive properties. And the motion circuit does a good job of handling the mineral. But it seems that at times when circuitry adds the ground signal to the target signal there is a tendency for some targets to read upscale too much on a tid. Is too much ground being added? Iron can read conductive too and its often how the loop approaches it, its position or its size: large iron is really bad on falsing. Loop fold-over is the non-linear characteristics of some loop designs that causes them to reverse signal polarity when getting close to mineralized ground and can cause erratic operation and this may have an effect. I can tell when I hit large iron that falses. And a near vertical nail will read high coin but will pinpoint off to the side 2--3 inches, As to silver falsing I have had rolls of silver quarters and halves read iron in air test, no idea why. Sometimes it all seems like a crap shoot and I just dig a lot more iffy signals...........you never know.

 

[vlad]

I guess now my question is, how does the ground balance affect the VDI/TID #'s. Does a negative ground balance # bring the coin/target VDI/TID # down? Does a positive ground balance # bring the coin/target VDI/TDI # up? What are the effects of target VDI/TID #'s versus the ground balance #'s? Lol I guess this is what I'm trying to ask. Thanks.

Surprisingly a wide variation in the ground will only move the TID a couple of numbers: its a different scale. (If it is on a unit set up in a different manner the TID will not move at all. For example a detector that reads
out in notches.)