Preset Ground Balance vs. Manual Ground Balance

[Dude]

This is more of a technical question.
What is the standard used to preset ground balance by the manufacturer?

The reason I ask is some of the places I hunt the ground changes enough to cause me to have to reground balance my one detector, but if I use my other detector that has preset ground balance there's no change in performance.

 

[TerraDigger]

I think the standard for the preset will vary from machine to machine, mfg to mfg. Maybe Dave Johnson Lead Engineer at First Texas will stop buy and give you a basic answer. Also the possibility that this type of info is proprietary and mfg's are not going to discuss the pre-set GB range parameters of their products

 

[Nauti]

Hi Dude,i think that detectors with a preset ground balance are set high enough to be able to cope with harshest of mineralised ground.This is good in one way because you very rarely get interference from any type of ground that you are detecting on and if you do you can slightly decrease the sensitivity which usually helps.However,a fixed balance is a bit of a compromise compared to a manually adjusted one.....manually adjusting allows a machine to cope with minerals at higher sensitivity settings which in turn can give you better depth on difficult ground.

 

[Critterhunter]

I don't care for detectors with a preset ground balance because they don't give you best performance possible at any given site. I also don't care for auto ground tracking on machines because it too can cost you depth and is not as precise as a manual setting. Auto tracking will often track out a deep target as you continue to swing over it. Trash and iron targets in the ground can also throw off the tracking of these machines and thus give less performance.

Better yet than manual ground balance is the technology that BBS (Sovereign) and FBS machines (Etrac/Explorer) use to compensate for the ground signal. These machines don't need a ground balance because they use a very different way to ignore the ground signal. It doesn't suffer from the same drawbacks that auto tracking on conventional detectors does. The way the Minelabs compensate for the ground signal is by taking a digital picture of the ground with and without a target present and comparing the two. This provides top performance in harsh ground and minerals, extreme depth, and better target IDs at depth. It revolves around the way the multifrequencies they use allow them to look at the ground matrix.

One of the bad things about conventional ground balancing is that it is a form of filter in which a filter is set to ignore the ground signal. Any time you use a filter to do that you will lose targets as they can also be caught up in the filter by the machine. A Minelab doesn't need for the target to "break through" a filter in order for a target to be seen by them.

 

[D&P-OR]

Neil----That's a pretty good (and accurate) description of gb IMO.----Also,I think the individual detector manufacturers that have pre-set gb for a certain model of detector(s) can be better or worse than another manufacturer with a pre-set gb on their model(s).-----That's been my experience with fixed gb detectors in my ground anyway & one reason why it's nice to be able to "tweak" the gb on even a pre-set gb detector (if need be) for your area(s).-----You know all this but maybe it will help somebody.------To make it the simplest and surest, a person can just go with a manual gb detector in the first place.--------Del

Hi Dude,i think that detectors with a preset ground balance are set high enough to be able to cope with harshest of mineralised ground.This is good in one way because you very rarely get interference from any type of ground that you are detecting on and if you do you can slightly decrease the sensitivity which usually helps.However,a fixed balance is a bit of a compromise compared to a manually adjusted one.....manually adjusting allows a machine to cope with minerals at higher sensitivity settings which in turn can give you better depth on difficult ground.

 

[skookum]

High,
In the owners manual of my Classic III Plus it states, that Whites set the pre-set factory ground balance just slightly positve of a ferrite sample.
What ever that may mean.
Mr. Bill from the forum here does make manual ground balance conversions for numerous Whites detectors.
According to every one that had these conversions done to their detectors - performance/depth will then improve when encountering difficult/mineralized soil.
Now from what I understand, Minelab just switches to a single certain frequency(from its

 

[TerraDigger]

Also, with auto-tracking, the unit can suffer badly in heavy trash. When the machine hits a target there is a delay while the machine resets it auto-tracking. Your coil may pass over a good target and never know it. The White's Spectrum/XLT has settings to circumvent this. My White's Silver Eagle, a stripped down Spectrum, does not.