Gold Bug Pro ground balancing & ground phase numbers

[Indahillz]

Hi, hoping one of the Gold Bug Pro brains trust could give me their opinion please?

I'm new to detecting & was wondering about the ground balance number and the ground phase number in the middle of the screen. In order to ground balance I'm pumping the coil up and down whilst pushing the GG button and most often the ground phase number and ground balance number match closely pretty quickly, however.....once I get started sweeping again the ground phase number (in the screen centre) jumps all over the place. Is this normal? Or should after I've ground balanced, the phase number pretty much remain the same?

I've read through the manual and I think I'm doing everything correctly, just not sure if an erratic phase number is right?

Thank you

 

[dfmike]

Once you release the GG button, your ground balance is set. If you start sweeping, the ground phase number changes because your detector ID's ground targets which will make the ground phase number change. The ground balance number will remain the same as long as you don't press the GG button again. Personally when I ground grab on my F19 I never pay attention to the number in the middle when ground balancing. I pay attention to the sound or lack thereof. I listen as I sweep until I hear no sound in the headphones. That means I have found a clear area to perform a ground grab. I usually ground grab in 2 different but close areas to check if numbers match closely. If they don't by a long shot, one of the areas was not free of metal. For example when I started detecting earlier today, I got a 85.6 in one area and a 86.4 in the other. Both areas were in close proximity That's close enough. Sometimes I will set the ground balance manually to average both numbers but usually I will keep the highest number. I will then put the detector back in discrimination mode. The big number in the middle then becomes the target ID number or value.

When I ground grab I usually set the detector to all metal, gain at halfway or 50 and threshold to a slight positive. It's sometimes hard to get a clean area but with a little patience I can find a small area somewhere where the detector stays quiet on while I sweep. Hope this helps.

 

[Hoser John]

great advise-john

 

[Dave J.]

dfmike's got it pretty much figured out.

Some ground is pretty bouncy, esp. if it's a mixture of clay and rocks. In that kind of ground there is no precise ground balance point, so you just pick what seems to be a representative number and do the best you can with that. In disc mode it'll hardly matter anyhow.

In ground that's lightly mineralized, the internal noise floor of the machine and/or electrical interference can bounce the ground numbers around even if the ground itself is uniform. In light mineralization the ground setting isn't so critical, so the approach is the same: pick a representative number, in disc mode it'll hardly matter anyhow.

 

[dfmike]

Dave J, when you mention that it doesn't really matter in disc mode do you mean any disc mode or only disc mode with actual discrimination setting or value applied ? I ask this because I only set the F19's knob to disc but at the absolute minimum value which some call disc zero. I gather a correct ground balance point will matter more in all metal ? Thanks.

 

[Dave J.]

Dave J, when you mention that it doesn't really matter in disc mode do you mean any disc mode or only disc mode with actual discrimination setting or value applied ? I ask this because I only set the F19's knob to disc but at the absolute minimum value which some call disc zero. I gather a correct ground balance point will matter more in all metal ? Thanks.

Correct ground balance is always important in all metals mode, unless mineralization is very light. In discrimination mode generally speaking not so important, although that detail depends on what specific model and what "zero" or "minimum" discrimination really means on that machine. On most computerized machines, discrimination doesn't go past the ground balance point, either because it begins past the range of iron minerals, or because the software stops it from going below the actual ground balance setting.

I don't remember the specifics of the F19 in that regard (I helped develop algorithms but did not code the software). In any case, the bottom line is what actually happens when you use the machine. If you're getting appreciable amounts of ground noise, you probably need to increase the discrimination setting to "discriminate it out".

 

[dfmike]

Thanks Dave.

 

[MikeW]

does it matter if the coil is closer to the ground or 6-8 inches off the ground when releasing the GG button? I get several sets of matching numbers when pumping the coil up and down,, like 70/70, 55/55, 30/30. Seems like the higher numbers are off the ground and lower ones closer to the ground but not sure on that.

 

[dfmike]

I doubt it really matters. I never paid any attention if the coil was up or down when I released the GG button. In any case once the phase number stabilizes it stays the same for me whether the coil is up or down (closer or lower to the ground). Dave J. can chime in here.

 

[MikeW]

Thanks for the reply.