Jump to content

Effects Of Ground Balance On Target Depth?


Recommended Posts

13 minutes ago, Jim in Idaho said:

I'm not trying to convince anybody of anything.

Me either Jim. People often assume agendas where none exist. All machines serve somebody in some way whether it be in features or affordability. I am convinced anyone with any decent detector can do well as long as the machine is appropriate to the task. The goal then is to just figure out how to get the best out of the detector. It's all about sharing information and helping each other regardless of brand and model. I wish everyone could just put brand loyalties and such aside and focus on the sharing and helping part.

Thanks for confirming John is not smoking old kangaroo hides! :biggrin:

  • Like 3
Link to comment
Share on other sites


The GB works fine. I've never had a problem getting it to balance anywhere I've used it.

Jim

 

Thanks for the reply. I'm just trying to learn something. Seems like a good detection distance for the 1grain bar.

Link to comment
Share on other sites

46 minutes ago, green said:

The GB works fine. I've never had a problem getting it to balance anywhere I've used it.

Jim

 

Thanks for the reply. I'm just trying to learn something. Seems like a good detection distance for the 1grain bar.

It surprised me, too. When I first started testing my coils, before the battery tests, I just wanted to know what to expect from my detector. I was disappointed when I tried cutting nickels into small pieces, and the detector couldn't see them very well. Then I tried lead shot, sometimes flattening it. That also wasn't very promising. I usually couldn't see anything smaller than 3  or 4 grains. Then Reg Sniff told me the pulse width used by Whites was optimized to get a reaction on gold. So, I bought that little 1 grain gold bullion bar. I was really shocked that the TDI SL had no problem seeing that....even with the 12" DF coil. I guess, from an engineering standpoint, it's possible to optimize the pulse width for whatever metal you wanted to find. Nickels electrical reaction is similar to gold, but nickel is much lighter (lower SG), so a 1 grain piece of nickel would be 2X or 3X the size of the same weight in gold.So when you're testing, there's no substitute for gold when testing a PI. in my experience, the VLF's are less critical about the metal used...but that's just my opinion.

Jim.

  • Like 2
Link to comment
Share on other sites

Don't go knocking my kangaroo hides, I got a new shipment just this week,, Far Out "n" Groovy  :cool:

Seriously though I did try to explain this to Reg and Carl about 2 years ago and I contacted Whites in Scotland too, And it was put down to the "Roo Hides" back then too,  I showed it to RickUK back in November 2015, and it had him scratching his head too, Nothing made sense with it and the people in the know were telling me I was not seeing what I saw, My tests did not match anything that was being posted elsewhere and left me wondering why they were putting down the machine,

That overload/reset trick was the thing that first alerted me to the GB on and off thing because I air tested a Quarter at around 15/16 inches and then it stopped whooing on it so I bought the coin up to the coil and tried again and it reset it's self out 15+ inches again giving me another thing to figure out added to the list, So I then tried it with the GB off and it did not work and the distance was now down to 12/13 inches and nothing I did would improve the signalling distance, So I grabbed the Pro and it did the opposite, being what we all know to be the "Norm/True" with the TDI series machines,

With my emotions put back in the box, I began to realize the benefits of the SL over the Pro from a Prospecting point of view, In hot and unpredictable ground we need to use the GB and the SL puts the power out with the GB on, In the same situation with the Pro with the GB "On" you are actually loosing depth compared to with it Off, The SL has always been seen as the Red Headed Stepchild, but in the situation above I think it has become the long lost Son.

Anyway, I hope I did not Hi-Jack the thread, Apology's if I did.

John.

PS, Good work Jim In Idaho.

  • Like 1
Link to comment
Share on other sites

I think Reg has come around on this, now, John. but he doesn't know, from what he's told me, exactly whats going on either. This whole thing may be just an "unintended consequence" of something Whites changed when shifting to the SL version.

Jim

  • Like 1
Link to comment
Share on other sites

I think the TDI would never be what they are without Reg, he is an extremely clever Person and I wish I knew 1/1000th of what he knows.

Not the most powerful machine in the world but they are a good work horse and perfect as a rough country machine.

J. 

  • Like 3
Link to comment
Share on other sites

Yup...I agree with all of that.

Jim.

  • Like 1
Link to comment
Share on other sites

John,

You have CROSSED THE LINE.

In a politically correct world and in metal detecting talk it is not acceptable to use the term Red Headed Stepchild.  Take your mean and misguided language and go some place else ... or stay here if you want to.  haha

Mitchel

  • Like 1
  • Haha 1
Link to comment
Share on other sites

I bought the TDI Pro for 2 site specific uses,but of course it will/can be used on other sites as well as,i use the Pro solely for deep work ie hoard hunting or on ground that has a ultra high mineral content.

On one of my farms that has 2 potential hoards on,one is a roman silver dinari hoard 25 coins in a 70ft radius this indicates a scattered hoard and 4 fields away 20 Celtic gold full staters once again in a tight radius and same characteristics as the silver dinari hoard,so my plan was/is to use the TDI Pro for not only locating some possible more loose coins but also hunting down the container or pot for a better word.This setup would be using the Minelab 15x12 Mono coil with GB off and using it just for the extra depth on both hoards.Alas we lost the site 2 weeks later due to some scumbag dropping litter and not looking after the landowners property,its been 2 years since the incident and the farmer has allowed just 2 folks back onto his 1000 acre estate so i will be back again after the crops come off in a month or so's time.

2nd scenario for getting the TDI is a permission that has a roman trading villa site on the permission and was used by the roman for about 400 years and of course the amount of coinage and other items that have been dropped is some what short of 'Amazing' running into 1000s of coins,but the twist is with this site is the fact that the ground is about as hard as it gets here in the UK its almost black sand like on the beach but 100 miles in land,very few VLF machine work on this site and then normally you can only get a few inches in depth,but the TDI with 'GB on' using low conductivity and the 14x9 Coiltek Mono works a treat,this of course allows you to still detect the roman coins which have included both silver dinari and gold coins as well but also reduce the digging of iron to a much lower amount than if GB was off.

So although its not gold nugget related it shows that the TDI Pro can work for you both way with the GB on or off and the various benefits that each one offers.

Of course this is just how i use my TD others may use it differently and of course thats the flexibility of this machine.

  • Like 4
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...