Adjusting for a different coil

[Woodrow68]

Anybody know where I can get instructions to calibrate a detector to a new coil, Deleon or Cortes?

 

Amazon Forum Fav 👍

How to Research for Treasure Hunting and Metal Detecting From Lead Generation to Vetting - Grab it through Amazon!

[gunsil]

I never had a Tesoro but I have never had to do any calibrations changing coils on my Garrett or Minelab machines. Just plug it in and go.

 

[Mojave1]

I never had a Tesoro but I have never had to do any calibrations changing coils on my Garrett or Minelab machines. Just plug it in and go.

I thought when you ground balanced that was the calibration although I have put larger coils and had success with preset ground balances.

 

[Woodrow68]

I never had a Tesoro but I have never had to do any calibrations changing coils on my Garrett or Minelab machines. Just plug it in and go.

I'm sorry, did I post in the wrong forum? Is this not the Tesoro forum? It's not a Garret or Minelab......................

 

[Woodrow68]

I thought when you ground balanced that was the calibration although I have put larger coils and had success with preset ground balances.

It's a preset ground balance in discriminate mode. All coils I have tried are somewhat unstable or alter the VDI.

 

[gunsil]

I'm sorry, did I post in the wrong forum? Is this not the Tesoro forum? It's not a Garret or Minelab......................

Doubt it matters where you posted it, the answer is still the same, plug it in and go. There is no calibration other than ground balance which one would do no matter what coil was used. Where did you get the idea one needed to re-calibrate detectors when changing coil size?? If you are having stability problems with coil changes there is something wrong and there is no "calibration" that will fix it. If your machine works well with one coil and not another there is a problem with the coil that isn't performing properly or it's wiring or plug. You could send it back to Tesoro and get it checked out, but wait! Tesoro is out of business!

 

[pinenut]

While I don't know if Pentechnic sold the Deleon or Cortes, they may be able to service them or possibly, tell you how to calibrate with a different coil. They do service the Tesoros they sell with their brand label and the “Laser Hawkeye” looks like it could be similar to Deleon or Cortes..

 

[gravityboy]

It's a preset ground balance in discriminate mode. All coils I have tried are somewhat unstable or alter the VDI.

I'm surprised that different coils make that much of a difference on the fixed ground balance Tesoro machines. I've heard others mention no issues switching to different coils that weren't explicitly tuned. You may get more falsing or less depth but that should be the only effect you are changing with an adjustable GB machine.

I haven't taken apart a fixed GB Tesoro but if you can find a schematic somewhere I'm sure we can figure out what pots tune the GB.

 

[digger27]

The procedure is pretty simple, grab a bunch of your dirt and pile it up then pump your chosen coil over it while adjusting the GB in tiny increments until it is quiet going both up and down...or as close to silent or even tones up and down as you can get.
Pretty simple but still dangerous for the unskilled...a little to far on the adjustment and you can easily brick the thing and make it unusable and should consider using it for a doorstop instead or those pots can be real fragile and break more easily than you can imagine.
Not to mention it you don't ground yourself even the smallest amount of static electricity can possibly fry parts of your circuit board.
Your property so do what you think you need to do but forget about sending it back to Tesoro if you screw up...a well loved option that is no longer available.


For a long time Tesoro has had their own opinions on this and their idea of "Optimum Ground Balancing".

First, you have to understand a little about ground balancing using ferrite rods which I believe is, or used to be the way manufactures set a GB on their products...especially on pre-set GB detectors.
George Payne explained it pretty well, here...
https://www.findmall.com/read.php?18,1766646

They might use different methods nowadays, for all I know, but the goal was to set the GB at a certain specific level to be used in the largest range of dirt types which is logical if you are selling products nationally or world wide but as we know there is a whole lot of different kinds of difficult dirt out there.
A pre-set tool that might work perfectly fine and optimally in the great black dirt I used to hunt in when I lived near Kansas City could be, and is, totally overwhelmed in my current red clay, mineralized SE. devil dirt...no matter what coil I use it could be way off from "optimal" settings set by the factory.
What worked so well out west could be close to useless here, or to be precise they would still work but not close to as well as it would with ground balancing ability and options.
What to do?

Tesoro, and most other knowledgeable hunters, always suggested for rougher dirt buy a detector with a manual GB and that should take care of any issues in changing coils or optimum GB'ing even in the toughest dirt, or at least GB to the best level possible.
For owners of the Silver, Cibola and all the other detectors Tesoro made that were pre-set this wasn't possible unless you knew how to get into your unit and adjust the GB trimmer to your specific problem dirt...or add a GB knob.
Some attempted this and did it right, others tried it and totally messed up their units to the point they had to send them back in to Tesoro to get them to recalibrate and adjust them to work correctly again because this procedure can go sideways quick if you don't know what you are doing.

Some hunters can get totally obsessive about this stuff, not me of course but some, so when they picked a coil they were happy using they sent it in and their Tesoro pre-set detector PLUS a big bag of their local dirt and asked Rusty or whoever to GB to that specific dirt.
This they did happily and for free and this is where the idea for optimum ground balancing using a specific coil on a pre-set ground balanced unit became a thing.
It probably wouldn't have if only the lowest units lacked GB but Tesoro made several very popular detectors that weren't entry level from the Cibola on up that were not cheap and frustratingly could not could not manually GB so sending in dirt and the coil and detector became a thing...for those not brave or skilled enough to adjust it themselves or add adjustable GB ability.
The one problem I found is in my area of the country the dirt can very wildly by moving only a few feet.
On my F70 I have hunted in sites that GB'd in the 50's but move around just a little, rebalance, and that number can change and go up into the 60's, 70's and even the 80's if I get into heavy deposits of the red stuff.
If I wanted to adjust the GB or send in the detector and dirt to get it factory and optimally balanced which dirt should I pick to send in?

Again, manual GB units never needed it and hunters that spent time in better dirt usually didn't either, according to Tesoro.
For those of us that hunt in problem dirt were just left with a couple of options...
1) Try to optimally adjust the GB ourselves or mod it and add in a GB pot
2) Send it in with some dirt and ask them to adjust it for you
3) Deal with it as it is and hunt all the while knowing you are not hunting as deep or optimally as possible
4) Buy a detector with auto, or better yet, manual GB abilities.

Sometimes this stuff can make a difference, my manual GB detectors work much better here than my pre-set Compadre ever did...as much as I love that little thing.
Where I live GB can possibly get me a little deeper with better ID's and around here even as little as an extra inch or two can make a big difference in the quality and quantity of what I can find.

So the opinion is, my opinion, anyway, is if you hunt in decent dirt you should be fine switching coils on pre-set units...you won't ever be perfectly optimal but you will be close enough for government work and shouldn't worry about it.
For those of us blessed with problematic soil and conditions we need to deal with what the factory thinks are optimal levels of GB or make a change because the "what if" feelings of hunting knowing you are not optimally ground balanced can weigh heavy on some...they just can't enjoy themselves knowing what they know.

Me, I considered sending in some dirt and my Compadre but instead I just opted for investing in detectors that have manual or auto balance options.
I still use the Compadre here and there, still fun but not deep, my Mojave is a different design and works better here than the Compade for some reason but when the going gets tough I am going with my F70 or the Nox...those more advanced detectors can deal with my dirt much better than any pre-set unit can and I can change in the fly if my conditions change.

Using my pre-set units I have found a bunch even in my bad dirt and I am still finding great things but those "what if" feelings might still show up from time to time.

 

[steve1357]

to repeat what I've learned by trial and error

use your largest coil to ground balance, when you do, the smaller coils will be a little negative

if you ground balance with a small coil, the larger coils will be to the positive side and really hurt performance....
ymmv

so if you send it in, send in the largest coil you plan to use.....

 

[Arkie]

Turn on off switch to on, hunt.

 

[pinenut]

I’m surprised that the OP got so many responses about ground balance when I think he was asking about calibrating a target ID machine. It not only requires a correct setting on ground balance, but also calibration of a pot for the target ID. I once bought a Cortes that the previous owner had fiddled with and it was way off.. I sent it back to the seller who then sent it to Tesoro.

I think it would be best to send a target ID machine to someone qualified and knowledgeable, for proper calibration.. Try contacting a few people to track down Carl who did repairs at Tesoro, or try Pentechnic in the UK. Of course if you don’t care that it works properly - then it won’t matter.
If your Cortes or Deleon doesn’t work right after adjusting settings, you might as well throw it on ebay, sell it and buy something else.

 

[GeoW]

There is that... I think that would be calibration of detector as opposed to
adjusting the coil...but actually there is no coil adjustment to be made aside
from having the chord shortened.

Sometime the English language is an adventure

gw

 

[digger27]

Here is a whole bunch of stuff about this and many opinions and experiences from owners.
Check out Monte's post since he used to be a Tesoro dealer and he still uses them today.

https://www.findmall.com/read.php?17,2332771

He says "tuning" a preset unit to a coil that was not originally specified to be mounted was always a thing that Tesoro did...basically they would tweak the GB trimmer to match the new coil to the unit better and achieve a more functional GB range.

I know for sure they also tuned and balanced over any strange dirt you sent in with the detector and coil.

 

[pinenut]

Here is a whole bunch of stuff about this and many opinions and experiences from owners.
Check out Monte's post since he used to be a Tesoro dealer and he still uses them today.

https://www.findmall.com/read.php?17,2332771

He says "tuning" a preset unit to a coil that was not originally specified to be mounted was always a thing that Tesoro did...basically they would tweak the GB trimmer to match the new coil to the unit better and achieve a more functional GB range.

I know for sure they also tuned and balanced over any strange dirt you sent in with the detector and coil.

Monte doesn’t use Tesoro’s target ID machines. He still says his two all-time favorite Tesoros are Bandido II μMAX and Silver Sabre μMAX, the later being one he tweaks the internal GB pot on to suit his coil and ground conditions. He also says he tweaks the GB pot on any others he’s used with a preset ground balance, but none of those happen to be target ID machines - which also need the target ID pot calibrated.

Again, on Cortes and Deleon - it’s not about ground balance alone. If the Cortes or Deleon in question were mine, and I wanted to fiddle with internal settings.. The GB adjustment is the first setting I’d get correct, then after I thought it was where it should be, then I’d attempt the target ID setting. It may or may not work properly though, once you move to different soil - but it may work well enough.

 

[Stoof2010]

Be careful with the Cortes/DeLeon and GB adjustments
Because it's a hybrid analog/digital machine, the GB directly affects the accuracy of the display and the bars. Other present machines that don't have digital processors can be adjusted quite easily but with how the DeLeon and Cortes are hybrid you can really throw off the probability graphs.
The Cortes has adjustable GB but only in all metal mode. Adjusting the GB in disc is much more complicated on these machines.
Not sure where you'd get it done but I wouldn't mess with my DeLeon. I had Tesoro set mine.
Now as long as you aren't making a large coil size change you should be ok. Little bigger or smaller and you should be ok.

 

[Slowtaknow]

I think most detectors have you remove batteries first, then replace them after the swap, but that may be limited to digital, i do it anyway.

 

[IowaRelic]

Not to hijack this, but my compadre with the 8” needs a new coil. I’ve been hesitant to spend the coin just to cut the cable and splice it to the compadre. I was thinking of doing a screw connection conversion, but am now leaning toward just splicing in a 7” concentric. This should be workable compared to the 8” without making any adjustment, should it not? I’ve always wanted to try that 7” coil and the compadre is the only epsilon machine I have anymore.