Ground Balance, Threshold and Sensitivity Settings

[ToddB64]

I have some ferrite samples, somewhere, but prefer to just adjust the GB for the sites I am hunting. I do, however, have a few specimen rocks from some of the more challenging ground mineral areas I hunt and I often use them to check GB adjustability and detector performance. On the Bandido II [size=small]micro[/size]MAX, as well as almost all other Tesoro models, I would adjust the GB in the Threshold-based All Metal mode to be 'spot-on' or ..if anything .. just very slightly negative in the All Metal mode. I would not increase or decrease the GB from 'spot-on' by ½ turn. That model uses a 3¾-turn GB pot whereas the original Bandido and Bandido II use a 10-turn GB pot and might still function OK with a ½-turn either side, but not the 3¾-turn pot.

Why do I suggest this, you might ask? Simple: Most Tesoro models have the Discriminate mode tied in with the GB adjustment, but the Disc. mode has a somewhat positive off-set from the All Metal mode. Thus, if you GB 'spot-on' in the Threshold-based All Metal mode, the Disc. mode is already slightly positive. If you turn the GB control an additional ½-turn more positive, that can often make the GB in the Disc. mode way too positive and it might not give a positive response to a US silver Dollar, and could even not respond to a Half-Dollar or, sometimes, even a Quarter.

The way Tesoro circuitry was designed [size=small](generally with most models)[/size] a peak-performance GB setting made in the silent-search Discriminate mode will have the Threshold-based All Metal mode just a bit negative. Still functional for Pinpointing targets, which is good because most folks use the Disc. mode almost exclusively.


ED-180 means ALL of the 180° "arc' [size=medium](upper portion of a sine wave)[/size] is Accepted, from Ferrous range on to the higher-conductive Non-Ferrous range, such as silver.

ED-120 means the lower 60° of the 180° 'arc' is NOT Accepted, and therefore they are rejected. That would be using the minimum Disc. setting on the Bandido II [size=small]micro[/size]MAX where most nails and most ferrous-based targets would be ignored, aka Discriminated or Rejected. Lower-conductive non-ferrous objects, such as small, thin foil or thin gold chains, etc., would just be Accepted at that minimum ED-120 Disc. setting on up the conductivity range to higher-conductive silver dollars. So at the minimum Disc. setting with ED-120 Disc., nails and most common iron IS going to be rejected.

NOTE: As with just about any detector offered with motion-based Discrimination, we can still have issues with some man-made ferrous-type objects, such as crimp-on Bottle Caps, round iron washers, etc.


The ferrite sample is used to adjust the Ground Balance in the All Metal mode, not to check the Discriminating abilities of the Discriminate mode.

Now, that said, I have used a ferrite sample, just as I do a very mineralized rock, to adjust the Ground Balance in the silent-search Discriminate mode. That is a technique I described as "Power Balancing" about 35 years ago or so. With my Bandido's I usually make a quick GB in the All Metal mode to be 'spot-on' or just very slightly negative. But I use 'Power Balancing' in the Disc. mode a little more often than GBing in All Metal just to be certain I have a peak-performance GB setting since I am mainly searching in the motion-based Discriminate mode.


I'm naturally not Carl, but I encourage you to not get too lost in terminology or definitions, or worry about the Bandido II µMAX as it is really rather simple. Just go out hunting and adjust the GB to the particular site you are hunting. Quite often I adjust the GB on mine to be 'functional' for my area and just turn it on and start hunting in most places. If there has been a significant change in ground mineral make-up, I'll know it right away and can make a GB correction in 5 to 10 seconds. If you're stuck indoors during the winter wherever you are, you can use a ferrite specimen or a good rock and just practice Ground Balancing at home.

Monte

 

[ToddB64]

Monte,
In your last paragraph you say " If there has been a significant change in ground mineral make-up, I'll know it right away and can make a GB correction in 5 to 10 seconds.

How do you "know it right away", i.e. what manifestation occurs while you are presumably sweeping the coil for targets ? Wouldn't you have to be Ground Balancing and hearing Positive or Negative sound responses as you raise and lower the coil in order to "know it right away", or is there something else that tells you the ground mineralization has changed while you are sweeping the coil hunting and what would that something else be ? Please clarify.

Thanks,
ToddB64

 

[Monte]

ToddB64:
Monte,
In your last paragraph you say " If there has been a significant change in ground mineral make-up, I'll know it right away and can make a GB correction in 5 to 10 seconds.

How do you "know it right away", i.e. what manifestation occurs while you are presumably sweeping the coil for targets ?
I would "know it right away" usually because I find stuff and that means I use the All Metal Pinpoint function, and that lets me know right away that my Ground baland stting is a little off. Maybe not enough to be concerned, but if the grodund mineral make-up has changed significantly, I few seconds and I'm back to a more functional GB.

ToddB64:
Wouldn't you have to be Ground Balancing and hearing Positive or Negative sound responses as you raise and lower the coil in order to "know it right away", or is there something else that tells you the ground mineralization has changed while you are sweeping the coil hunting and what would that something else be ? Please clarify.
I'm in All Metal when I'm using the Pinpoint fature so it's a quick alert of the GB is 'Off' a little too much.
Additionally, during the search in the motion-based Discriminate mode, if I move into an area that is more mineralized than the location where I Ground Balanced, and it is a significant change, then I might have a too negative GB setting. That would alert me with an uplift or the coil away from the ground, or a beep if I sweep over a hole, a furrow, very uneven ground, or void, etc.

Monte