Sensitivity on the X 50

[North Georgia Relics]

I had the X 50 at an old house last Friday and everywhere I put the coil I got an iron reading. I think I read on the forum if that happens, I should have reduced the sensitivity which was set at 17. Is that correct? I can't find the original post.
Thanks in advance.
Don

 

[Digger]

You didn't mention how you ground balanced the detector. That may be the root of your problem. I would recommend that you lower the sensitivity to single digits, then ground balance the X-50 at that lower setting. After getting a proper GB, advance the sensitivity until it reaches a point that it creates false signals. Decreasing the sensitivity may allow you to stabilize the X-50. But your depth of detection will increase as you increase the sensitivity. The objective is to run the X-50 with the sensitivity as high as you can, without causing the detector to become unstable. HH Randy

 

[North Georgia Relics]

Hi Randy, thanks for the advice. The ground balance was slightly positive at about 8 if I remember corrrectly. Had a problem finding a place balance the machine. Next time out I will lower the sensitivity prior to ground balancing as you suggested.

 

[Monte]

your discriminate mode was or the site environment.

I did note that you said: "The ground balance was slightly positive at about 8" For some areas of the country that will work just fine, and it might be a little "positive" if the rest of the ground in your area is balanced out at perhaps #10 or so, but a setting of #8 is totally unworkable here where I live in NW Oregon. Matter of fact, the X-Terra 30, which is also a darn good unit, just can't handle our ground and it has a factory preset similar to a #6 on the X-Terra 50, and #6 is a more positive setting than your #8.

At only a few sites here can I get away using my X-Terra 50 at a setting of #5, with most sites requiring a #4, and too many that need to have a #3, and some really mineralized locations where I have to use a #2 GB setting. That's about as positive a GB setting as you would want to deal with!

Now, I almost always operate with a Sensitivity setting of '20' and I also try to hunt in the motion All Metal (zero discrcrimination) 'mode'. Doing so you can often hear the low iron audio and get the iron indication from what is iron as well as from some hot rock issues, BUT if I reduce the Sensitivity a little (I never have hunted less than 12, and then only twice), or the easier way is to use Pattern 1 and just reject the first two segments (-9 and -6), it helps. More often than not I just go to Pattern 1 set-up as noted and that takes care of it.

It is important to make sure the GB setting is done correctly, and to have it as close to 'proper' as possisble. I have found the X-Terra 50 does best when set as instructed and NOT to set it slightly positive (a lower number) or slightly negative (a higher number).

As Randy and some others have commented, it can help to reduce the Sensitivity a little to set the GB, and usually smooths things out better when reduced top maybe 12 to 16.

Of course, there's always the possibility that there was a lot of iron nails and such around the old house site. That sometimes happens.

Monte

 

[North Georgia Relics]

Thanks Monte. There is no telling what was on this property before the house was built. Should have been some CW relics & old coins there. Probaly had been hunted before, but something is always missed.
When I said that it was balanced slightly positive that was as close to neutral as I could get it. There have been very few sites here in NW GA that I have been able to get a good neutral balance, so I have elected to go a little positive vs using the negative side. Possible that lowering the sensitivity will help that situation. If not, maybe I should try going with slight negative, reduced sensitivity and see how that works.
Thanks again.

Don

 

[Ralph Bryant]

....and confusing to most detector users because there is no rhyme or reason when such terms are used in different directions.

Example: Higher GB numbers on the Xterra means lower mineralization levels (not really) and lower numbers mean higher levels (again, not really). Ground phase has nothing to do with "how much" mineralization is present, and is only an indication of the "kind" of mineralization present.

On the White's conductivity or VDI scale, higher ground phase readings are toward the lower end of the scale, or more magnetic and less conductive. You have opposites in types of ground mineraliation that we are trying to group into a single terminology.

High or low mineralization relates to the magnetic susceptibility of the ground on the lower ferrous end and conductive response on the higher or conductive salts end. It's like trying to clock two vehicles on radar going in opposite directions with the same radar unit.

But it is all relative, and "balanced is balanced". Once you are positive or negative, then you are no longer balanced. In actual terms of the true VDI or phase scale, low is at the magnetic ferrous (ferrite) end, and high is toward the conductive or non-ferrous (silver) end. So the higher the ground phase, the lower your "true" phase using the White's scale. Remember that the White's phase scale is artificially zeroed at what amounts to the 90 degree point of the true phase scale, so the ferrous side of the scale is effectively "backwards" from reality.....95 to zero rather than zero to 90.

Unfortunately there is no set standard, and that is what really causes the confusion IMO.

Ralph

<center>[attachment 16342 DiscriminationChart.JPG]</center>

 

[North Georgia Relics]

Wow Ralph that is technical and I can't even pretend to understand it, but I intend to read it over several more times. After 30 years of detecting. first detector was a BH BFO, this is the first time I have seen that explained. Thanks for taking the time to explain how it really works.
I should have said that the best I have been able to do in ground balancing the X50 is to get it to the point where there is a slight increase in sound when I lower the coil. If I lower the setting by 1 number, then there is a slight decrease in sound when i lower the coil. I do not let the coil actually touch the ground but keep it about an inch above the ground. Is that correct?

 

[Digger]

Couldn't have said it better myself. Seriously. I couldn't have! HH Randy

 

[Monte]

Don't tinker with the "too negative" or "too positive" on the X-Terra 50. The X-Terra's function (GB) a little different from some other makes and models and you're really better off with a properly set GB. If it's difficult to estanblish at a higher Sensitivity, then reduce the Sensitivity until you know you can make a good GB adjustment.

Monte

 

[Digger]

As I have mentioned, your objective is to set the GB where the high tone and low tone merge. Completely eliminating both is nearly impossible as soil conditions vary "inch by inch". Over the past 3 months, and hundreds of hours on the X-Terra 50, I have only had the GB tone "go silent" on a couple of occassions. Just let them "meet in the middle" and enjoy the hunt. HH Randy

 

[Ralph Bryant]

Tuning slightly to the positive side of the ground balance point (as you describe) is "usually" the best for helping the detector get a little better signal response on small and fringe range targets. It's best to balance to the level above the ground that you generally sweep the coil. In your case, if you keep your coil an inch above the ground while hunting, then balancing to that same height will tend to work best.

The problem with the X-50 and others with non-linear ground balance controls is that the segmenting doesn't really allow for much precision in the ground balance setting. This is not usually a major concern though in most places, since the ground tends to change a little in either direction anyway. "Close" is usually good enough for most types of hunting, and why pre-set GB machines work well in a wide variety of ground conditions.

Ralph

 

[Monte]

but all too often we can get into an "overload" of technical terms and descriptions. Positive Vs Negative. Conductivity Vs Conductance. The use of the term "mineralization," and others are, or can be, rather confusing.

There are only a handful of people who have a deep interest in this hobby to the point where they might appreciate nit-picking the fine points of the differences. Heck, just saying the words Manual Ground Balance is enough to totally confuse or scare off many hobbyists!

Manufacturers have added to some confusion thru the years by trying to be too technical or 'cutesie' with terminology, too. Heavens, for those of us who remember those first White's Cion 5 Supeme's you had to adjust two controls to establish a working ground balance on those non-discriminating units. The Tuner was easy to say, but White's chose to use "Terranian Attenuator" and I know for a fact that many dealers couldn't even pronounce it!


The approaches many manufacaturers take to incorportate a ground balance adjustment is also different within the industry and so I feel that it's best to minimize a lot of the confusion. One way is to use the 'standard' or ' industry accepted' terminology, and i this case it is "mineralization."

Naturally, ALL ground environments are "mineralized" to some degree, and even then there are variables, based upon how porous or compacted the ground is, or if it is bone dry, damp, moist, or well soaked. Even then, these are issues brought about by how deeply is it wetted?

Florida's pristine beaches are almost neutral, but are still "mineralized" and there are some changes there, too, between dry, damp and soaked. From there you can move on up the rungs of "mineralization" as the types of mineralization change and go to mellow to mild to fair to challenging to nasty.

The Ground Balancing or Cancelling or Neutralizing circuitry was developed from using the lower-end of the discriminate range. The graph you poste is an 'OK' representaion IF you're only tring to explain some Discriminate range braskdown, but doesn't fully explain the ground signal and "mineraliztion" we have to deal with, nor the effects of an out-of-adjustment GB setting, unless you used the full cycle of a sine wave.

Like you concluded with, there is not a set standard, but there is the accepted description of "mineralization" that is used by manufacturers and most detectorists to describe the low, moderate, or highly minerlaized ground environment they are in.

I also agree with you that it's best to use a proper "ground balance" ... but that might call for a slightly 'positive' GB with some makes and models , or slightly 'negative' with others, in an All Metal mode for proper or best performance out of the Discriminate mode. It all depends on how the manufacturer ties in a manual or autotracked GB with the Disc. mode, or where it might be preset, if that was their decision.

Dang! I sure wish the rain would let up some I could just go hunting and ignore the urge to post sometimes!

Monte

 

[dfwdetector]

So would it be correct to say drop the sensitivity to say 8 or so then ground balance then bump the sensitivity back up to 14 or 15 as long as the machine is stable?

In other words does the machine have to be ground balanced at the sensitivity level you use or is the ground balance the same point regardless of sensitivity?

Thanks.

dfwdetector

 

[Ralph Bryant]

...but if it weren't for the "nit-pickers", the machines would be full of all kinds of bugs (no pun intended).

The basis of my "not really" comments stem from some of the very points you make in your post, in that ground mineralization phase angle (ground phase) and "good or bad" ground is really a matter of qualitative vs. quantitative, "type" vs. "how much". You can have much "worse" ground mineralization at a ground phase reading of 80 than one at 90, or visa versa, so simply using ground phase to determine your ground mineralization is only part of the equation. It is much the same in comparing two metallic targets of identical "conductivity" without taking into consideration the "conductance" right along with it. Obviously, in this case, the larger of the two targets will provide the higher "effective VDI" reading. Use my old copper BB vs. copper bowling ball analogy, or a thin piece of aluminum foil compared to a large block of solid aluminum. Which one is easier to detect and causes the greatest "reaction" to the detector ?

My original point though was that there is not so much a problem of "technical terminology overload", but a problem of non-standardization of terms that tend to fly off in different directions at the whim of the different manufacturers. Too many times they seem to confuse things for the sake of clarification, exacerbating the original problem.

Ralph

 

[Digger]

Ground balancing should be the first priority. Then set the sensitivity as high as allowable for the site.
So, without knowing what type of mineralization you are dealing with, I recommend setting the sensitivity in the lower portion of the scale. Heck, set it at 4 or 5 if you want. Then ground balance the detector. Once you get the high tone and low tone to "meet in the middle", THEN you can raise the sensitivity to optimize the performance of the detector. At the majority of sites I hunt, I can run mine at 20 with very little chatter. Increasing the sensitivity after ground balancing will not change the neutralizing effect that a proper GB setting has on the soil under the coil. HH Randy

 

[dfwdetector]

Super, Thanks! That should make it real easy. I know with the Whites anytime you adjusted the preamp you had to re-ground balance.

dfwdetector

 

[North Georgia Relics]

n/t