TECHNICAL GROUND BALANCE QUESTION

[idig3]

using manual ground balance in this area where there is little to no mineralization, no matter where you turn the dial there is no change
in the threshold tone. I was told then it really doesn't matter where you set it ,or set it somewhere in the middle. But what i did notice
as i was experimenting with it in a dime test garden is that the more
clockwise you set it the less it saw deeper, somewhere in the middle
it got broken signals but still very noticeable. full clockwise(positive)
it completely missed deep ones, full counter clockwise (negative)
it got good clear signals on the deep ones.So my question is the more
negative you turn it does it make it go deeper? And would the same hold true in an area with heavy mineralized soil? One thing that i realized
is that with a manual gb set it wrong and you could be missing, but on the other hand set it right and you could see an advantage over preset.
Could anyone help with this

 

[Hightone]

From the Tesoro site:

"Factory preset is the most common type of ground balance. It is used on most machines that are called

 

[Hightone]

The ground balance knob needs to be turned as you raise and lower the coil to about 2" from the ground. Turning it while having the coil sitting in one spot does nothing.

 

[Wirechief]

It seems so in this case but if you had lots of ground responses and you set your GB control way negative then any weak positive responses from good targets can be masked. This is probably why even though you don't have a lot of mineralization it is better in most cases to set the GB just slightly positive. So the GB setting is always very important to get it set right. Ok I hope this helps somewhat and best to you.

John Tomlinson,CET
John's Detectors

 

[Myron]

understand what ground balancing does and how it works. This is explained in the manual and/or at the Tesoro website.

I've never experienced a site with no ground minerals whatsoever. You must have basically blow sand.

To set ground balance you must set your detector on all-metal mode with a barely audible threshold. Then you look for a place with no target in the ground. Once (or if) you find such a spot, this is where you ground balance. If there are any metallic objects in that ground your ground balance won't be right. This is why some people claim their Tejon's or V's aren't deep. They attempt to ground balance over trash.

To ground balance you hold the coil 2 feet high and then lower the coil toward the ground keeping the coil level with the ground. Stop lowering at about 1-2 inches above the surface.

If there is a rise in threshold, turn the balance knob toward the negative. If there is a drop in threshold, turn the GB knob toward the positive. What you want is a very slight positive threshold. Now switch over to discrimination mode and you're good to go.

One thing that is greatly misleading is the teaching (some by Tesoro) that manual ground balance machines must constantly be adjusted to ground minerals. This is absolutely false!

When one sets one's detector at a given site one is always much better off than one who orders a factory preset that was set for soil in another state or according to a standard ground balance.

When one sets a Tejon one time at a local site and never again adjusts that Tejon one has a preset machine. In this case it was preset by the owner instead of some factory person.

The sum is this, with a factory preset you are limited in that you can not change the ground balance. With the manual adjustable GB machine you have the option of preset or adjustable.

I have found with my Tejon that I rarely have to readjust the ground balance. In fact, I'd have to really screw it up on purpose to even start to lose depth.

Back to your soil, I'd just bury targets and keep adjusting the ground balance until I got the best depth.

But I must say that in 40 years of detecting all over the country I've never found a site that didn't require ground balancing.

You have very interesting soil indeed.

Myron

 

[idig3]

thanks for your help john but still a little confused. Why is then when
i set it all the way neagative it picked up more than when it was set
positive

 

[idig3]

thks myron the soil here is real just sugar sand the only dark soil
is the part on the back of a piece of sod. Back to your gb instructions
do you always have to keep the coil moving as you turn the knob

 

[Scully]

Some times its just easier to explain than type.

Gene Scullion, 608-213-6622

 

[Myron]

[quote idig3]thks myron the soil here is real just sugar sand the only dark soil
is the part on the back of a piece of sod. Back to your gb instructions
do you always have to keep the coil moving as you turn the knob[/quote]

No, I just lower the coil and if the tone increases in volume too much I then just stop and turn the balance knob about 1/3 of a full turn in the negative direction. I check it again and if it has gone a little too far (too negative) then I ajust the knob back toward the positive about 1/4th of a turn and check it again.

See it's sort of a go back and forth thing until you hear that right slight increase in sound volume.

The idea again is for a slight rise in threashold volume as you lower the coil over a spot free of any metal.

Myron

 

[Hightone]

An easy way to GB is to pump the coil up and down, keeping the coil parallel with the ground. Now picture the GB knob like a radio volume knob. If, on the down stroke, the threshold gets louder, turn down the knob until you have a steady tone while pumping the coil. If you lose the threshold while the coil is going down, turn the knob up, raising the volume till the tone is steady while the coil is moving up and down.

Steady tone means it's ground balanced.

 

[Wirechief]

It doesn't sound like your doing something quite right.

John Tomlinson,CET
John's Detectors

 

[idig3]

tesoro and there video say nothing about the coil has to move while you turn the knob, and if you watch the video he ajusts it without moving
the machine

 

[idig3]

i know how to gb the machine all i am saying is that i did a little
experiment where i am and i noticed you could go deeper with it all the way negative. unless you have experienced sugar sand there
is virtually no change in the threshold tone no matter which way you change the knob on any brand machine. maybe it's the soil here or i should say lack of soil. from the top of the ground down there is no black dirt just plain sand like you would find at the beach. As a matter of fact it is even hard to grow plants unless you import some soil and many experienced people that are in clubs here will tell you there is virtually no mineralization in the ground unless you go out
into the water at the beach. as a matter of fact tesoro and there video
say nothing about having to move the machine up and down at the same time you turn the knob. In the video you can see he keeps the machine still in one place as he turns the knob.

 

[idig3]

thanks for your help scully i know how to gb the machine all i am saying is that i did a little experiment where i am and i noticed you could go deeper with it all the way negative. unless you have experienced sugar sand there is virtually no change in the threshold tone no matter which way you change the knob on any brand machine. maybe it's the soil here or i should say lack of soil. from the top of the ground down there is no black dirt just plain sand like you would find at the beach. As a matter of fact it is even hard to grow plants unless you import some soil and many experienced people that are in clubs here will tell you there is virtually no mineralization in the ground unless you go out into the water at the beach. as a matter of fact tesoro and there video say nothing about having to move the machine up and down at the same time you turn the knob. In the video you can see he keeps the machine still in one place as he turns the knob.

 

[idig3]

thanks myron that's what i am doing if you read my other reply in this thread you see what i mean

 

[Hightone]

as a matter of fact tesoro and there video
say nothing about having to move the machine up and down at the same time you turn the knob

Doing it the way I said is just faster. You can drop the coil listen to the sound and hold the coil upwhile adjusting bit by bit, or as you pump the coil up and down, adjust + or - while listening to your downward pump until there is no change.

. In the video you can see he keeps the machine still in one place as he turns the knob.

Watch the video again. The first part, he takes a piece of ferrite and uses it to simulate the ground, and moves it towards the coil while the detector is on the table. The second part surely shows him moving the coil towards the ground to see if he needs to adjust + or -. At least the video I saw did.

 

[idig3]

yes i agree you have to move the coil to keep checking it until right,
but what i was saying is that you don't have to move the coil and turn the knob at the same time acorrding to tesoro. Doing it the way you say
would make it faster i agree

 

[Desert_Rat]

WOW I've never hear that one before. I adjust the GB at top and then lower it back down, and have no problems. So your saying that you should keep the coil moving up and down while adjusting the GB? Have you ever seen the Tesoro Video on GB a detector?

 

[Hightone]

(uh boy) Yes I've seen the video. I learned this method from a person that's been hunting for years. He showed me that way and it's much faster. Because Tesoro's have a fast recovery rate, you can do that with them. Pumping up and down on the ground (about 1 pump per second) and the unit will follow with a sound going down or coming up. Use the GB knob as if it were a radio knob. Turning it until the sound is equal (or doesn't change).