Tejon ground balance

[whitworth451]

hello, anybody have trouble ground balancing in HOT heavy mineralized soil? does it matter if the coil is over a hot spot as long as there are no targets below it?

 

[Rick N. MI]

In high minerals you need a wide scan coil. The Tejon I hear has a hard time in high mineral ground. Wide scan/dd coils you really need.

Rick

 

[KennyD]

I didnt want to start a new thread on this, but I have a question about Tejon ground balance for all you pros out here.....

Ive seen a few videos about ground balancing the Tejon, and they say to adjust it to where you get a slight sound while raising the coil.
This dosent make sense to me as all other machines balance to a quiet response on the upward and downward moves.
Even the users manual says to make it quiet that way.
Are these guys in the videos wrong? Or is there a real reason to make it sound off on the upward movement of the coil? And does it really make a difference?

 

[MarkCZ]

I didnt want to start a new thread on this, but I have a question about Tejon ground balance for all you pros out here.....

Ive seen a few videos about ground balancing the Tejon, and they say to adjust it to where you get a slight sound while raising the coil.
This dosent make sense to me as all other machines balance to a quiet response on the upward and downward moves.
Even the users manual says to make it quiet that way.
Are these guys in the videos wrong? Or is there a real reason to make it sound off on the upward movement of the coil? And does it really make a difference?

I think what your asking about is leaning towards the term "Power Balancing" the Tejon. I've never been able to ground balance to the point of NO Audio change, but I do get it to just a quiver. There has been some topics on this forum about Power Balancing. I'm pretty sure Monte can explain power balancing.

Mark

 

[KennyD]

Thanks Mark. This has been bugging me for quite some time....

 

[Monte]

Yes.

With any particular manual GB detector model? Yes.

hello, anybody have trouble ground balancing in HOT heavy mineralized soil?

No, not really. No more than I do with my Bandido II µMAX or with an Eldorado or an Outlaw. I can adjust my 'original' Bandido or a Bandido II easier, or let's say a little more "fine tuned," than the newer models, but that's because they have a 10-turn manual Ground Balance adjustment compared with the 3¾-turn GB adjustment on the other models mentioned, which is the same limited adjustment function on the Téjon GB.

One other difference between an assortment of models is also the operating frequency, and the Tejón's higher frequency might make it just a little 'touchier.'

does it matter if the coil is over a hot spot as long as there are no targets below it?

Well, kind of, because the more sensitive the detector is, the 'difficulty' factor has to be taken into consideration. Once you have established the fact that spot where you'll adjust the Ground Balance is metal free, then the only concern is mostly the size of the search coil used [size=small](larger size coils see more ground)[/size] and the Gain or Sensitivity level used [size=small](IF the All Metal mode has a variable Gain because many only have that tied in with the Disc. mode)[/size].

There can be other things to consider, too, such as the search coil's position from the ground as it is lowered to make the GB adjustment. Note that many/most manufacturers suggest working the search coils an inch or two off the ground. That's because a closer position can cause a fold-over effect, especially if the ground is very mineralized and if the search mode has a rather high Gain setting. Often, in a more severe mineral environment. you can hear the audio Threshold fluctuate [size=small](such as a pronounced increase then nulling or a nulling then an increase)[/size] when the coil is lowered below a 2" height. That, alone, can make it seem more difficult for some people to adjust the GB for a 'proper' setting.

I enjoy using some detector models with an 'automated' GB feature, such as the Makro Racer, Nokta Force CoRe, Teknetics Omega or White's MXT Pro. Generally, that adjustment function works okay. The first three of those models also provide me the option of making a manual GB adjustment, which I prefer to do [size=small](or at least be able to do if I want to tailor the setting in my favor )[/size]. I also don't hesitate to grab one of my 'preset' GB models, such as the Silver Saber II or Silver Sabre µMAX, but I have had the luxury of making sure I have tweaked the internal GB trimmer for a decent, functional GB for most sites I hunt [size=small](and I live in, and generally search in, highly mineralized ground)[/size].

For most of my ghost town, homestead, stage stop, encampment site, or urban renovation hunting where I am often dealing with both bad ground and ferrous and non-ferrous trash, the visual display model I currently grab most often in the Racer with automated or manual GB, but I prefer my proven performers, the manually Ground Balanced 'original' Bandido, Bandido II, and Bandido II µMAX Tesoro's.

The Racer uses a small DD coil I keep mounted full-time, and on my µMAX Tesoro's I keep 6" Concentric coils mounted, a 7" Concentric on the Silver Sabre II, a 7" DD on the Bandido II, and the 'stock' 8" Concentric on the 'original' Bandido. I have the stock 8" coils in a coil tote, but only use one, preferring smaller-size coils for the trashier conditions I generally encounter. I don't have any real problems adjusting a GB with any of them, even with their stock or smaller-size Concentric coils.

I have owned 3 Tejón's and never had a real problem [size=small](other than with the touchier course-adjustment 3¾-turn control)[/size] with the standard 'OOR' [size=small](Out-Of-Round)[/size] 8X9 Concentric coils. Just be careful to not move the GB control too fast or too far, and try to make a gentle adjustment as close as functionally possible. The high-Gain Téjon can be a bit touchy in severe ground, but it is doable.

Note that this thread discussion is referring to working in a Threshold-based All Metal mode and making a workable Ground Balance setting for searches in the All Metal mode.

Monte

 

[Monte]

I didnt want to start a new thread on this, but I have a question about Tejon ground balance for all you pros out here.....

Ive seen a few videos about ground balancing the Tejon, and they say to adjust it to where you get a slight sound while raising the coil.

That would be incorrect, IF you want to have peak performance in the Threshold-based All Metal search mode. You would want to adjust for, and try to maintain, a 'proper' spot-on Ground Balance. Matter of fact, when I select the All Metal mode to hunt, I actually want a very slightly Positive GB, and that means the Threshold audio would increase just barely as the search coil is lowered towards the ground. Set up that way [size=small](very slightly 'positive')[/size], the Threshold audio would null or decrease when the coil is lifted away from the ground.

This dosent make sense to me as all other machines balance to a quiet response on the upward and downward moves.

No, they shouldn't, not for a 'proper' Threshold-based All Metal search mode. They should be GB'ed to a point to try and maintain that slight audio Threshold hum, and to GB so that it remains silent could easily lead to a loss of depth and loss of sensitivity, especially to smaller targets.

Even the users manual says to make it quiet that way.

That is incorrect. Read the cut-and-paste below from the manual, noting what I point out in red.

Turn the detector on by rolling the SENSITIVITY knob clockwise to about 9 or 10 on the dial. You will hear the battery test to let you know the detector is operating. Next, adjust the THRESHOLD knob until a slight, steady hum is heard. The machine is now ready to be ground balanced. Next, find an area that has no metal targets in the ground, as this may give false readings while in the ground balancing procedure.

As shown in the photos, raise your searchcoil about 6 to 8 inches off the ground. This is high enough so that the detector will no longer read the minerals in the ground. While listening to the threshold sound, lower the searchcoil to about 1 inch off the ground. As the coil is dropped. This is the balanced response. When you get a balanced response, the detector is telling you that it is ready to hunt.

The positive and negative responses are easy to adjust. If you get a positive response, turn the GROUND ADJUST knob toward the minus sign on the face or in a counterclockwise direction. Getting a negative response means turning the GROUND ADJUST knob toward the plus sign on the faceplate or in a clockwise direction.

Here is an example of balancing: After setting up the detector, you raise the coil and then push it to the ground. As the coil drops, the threshold hum gets louder. You then turn the GROUND ADJUST knob counterclockwise toward the minus sign. You pick up the coil and push down again. This time you get a slightly negative response. Turn the GROUND ADJUST knob a little bit toward the positive or in a clockwise direction. When raising and lowering the coil, the threshold makes no change as the coil is dropped. At this point, the detector is balanced for the area and is ready to hunt.

Ground balancing is a learned skill, one that you should practice often. It is easy to practice almost anywhere— your front or backyard, a local park, or a fair-sized flower garden. When you are practicing, make sure that there are no pieces of metal underneath your coil that may cause a target sound.

So you are instructed to adjust the Threshold control to hear a slight audio 'hum' which is the Threshold audio level.

It then explains to adjust the Ground Balance so that when finished [size=small](if you can get it close to spot-on)[/size] you can raise and lower the search coil and there is no change in the Threshold. In other words, it means that you can raise and lower the coil and the Threshold audio hum doesn't change [size=small](get louder or quieter)[/size], but retains the 'proper' Threshold 'hum.' It doesn't say it stays quiet, and you wouldn't want it to, if you are searching in the Threshold-based All Metal mode.

Are these guys in the videos wrong?

It sounds like they are to me, if they are adjusting in All Metal to search in All Metal. I'd have to see the vireo you are referring to. You could e-mail that link to me at: monte@ahrps.org

Or is there a real reason to make it sound off on the upward movement of the coil? And does it really make a difference?

Yes, there might be a reason to have an audio response in the All Metal mode as the coil is lifted away from the ground, which would suggest it would have a negative GB [size=small](nulling as the coil is lowered toward the ground)[/size] depending upon the particular make and model detector and how the GB adjustment circuitry is tied in with the silent-search motion Discriminate mode.

If you bob the search coil while in All Metal and get a 'beep' or increase in audio hum as the coil is lifted away from the ground, that indicates you have a negative Ground Balance.

The question I would have at this point of the discussion would be this.:

Are you checking the GB setting of a Tesoro for performance in the Threshold-based All Metal mode, or are you checking the GB setting for use in the silent-search motion Discriminate mode?

This can be important with some [size=small](many?)[/size] Tesoro models because of the way the circuitry was designed. For example, all of the five Tesoro models I have in my personal arsenal, be them a 'preset' GB or manually-adjusted GB design, have a circuitry where the Discriminate mode 'reference' is somewhat positive from the manually adjusted [size=small](internal or external)[/size] All Metal GB setting. The same was true of the Pantera's and Golded Sabre II's I had, the Sidewinder µMAX and Conquistador and Conquistador µMAX, and many, many Tesoro offerings.

Many other Tesoro models are also so designed, and that means that a 'proper' or 'spot-on' Ground Balance in the Threshold-based All Metal mode results in a Discriminate mode that has a somewhat positive Ground Balance. So if the All Metal Ground Balance is set to be positive to some degree, the Discriminate mode GB function reference is even more positive. That can be detrimental to achieving the best performance because if the Discriminate mode's Ground Balance is TOO positive, you can start to lose responsiveness to higher-conductive targets, especially the more conductive ones such as larger Silver Dollars or a Silver or Clad Half-Dollar. Matter-of-fact, it's possible to have the Disc. mode GB be so positive that you can lose responsiveness [size=small](reject)[/size] Clad and Silver US Quarters and have a terrible impact on the detection depth of a Dime!

I don't know about you, but I like to find those targets and not lose performance when hunting any older-use site that just might have such targets present. No, there aren't as many today as their used to be, but they are out there. I learned long ago with some other brands that this design glitch could exist, and have monitored all Tesoro models I have owned and used since July of '83 when I started using and selling Tesoro detectors when the Inca was introduced.

Because of this All Metal Vs Discriminate mode GB circuitry design, I learned decades ago that I had to adjust the GB setting for peak performance in the mode I planned to search in. If I am hunting a plowed field or other location in the Threshold-based All Metal mode, I am going to try and have a 'spot-on' to very slightly Positive Ground Balance in that mode. That means as I lower the search coil from about 6" down to about 1" from the ground, I will hear a steady Threshold hum or a very slight increase as the coil nears the ground. Just slightly positive. Thus, if I then lift the coil away from the ground, it will either remain the same hum [size=small](if 'spot-on')[/size] or null out [size=small](if the GB is slightly positive)[/size].

However, if I am going to hunt in the Silent-Search Discriminate mode, and I know that it is already, by design, somewhat positive from the All Metal Ground Balance setting, then a 'proper' slightly Positive All Metal mode GB would then be too positive for the Discriminate mode. To adjust the Discriminate mode for a best performance Ground Balance setting, I would need to reduce the manual GB control and that could result in the All Metal mode then being a somewhat Negative GB.

But how do you adjust the Ground Balance setting for the Discriminate mode when it is a motion-based, silent search leaving you no Threshold audio reference? The answer is to use a method that I started using and teaching in my seminars about ± 1981. It can be done with models that have a Threshold Discriminate mode, but is especially useful for all Tesoro's and other brands of silent-search Discriminators. I coined the term "Power Balancing" and it is rather easy to do.

First you adjust a proper Threshold hum in the All Metal or Pinpoint mode, and it's helpful to GB in All Metal as well to have a starting point, then select the Discriminate mode. Set the Discrimination level to the minimum setting. Then briskly bob the search coil from about 6" [size=small](the length of any US paper currency)[/size] down to about 1" and back up. While doing this you slowly reduce the GB control towards the negative ... s-l-o-w-l-y. As soon as you hear a 'beep' on the UPLIFT of the coil away from the ground ... STOP. That means you have adjusted too negative for the Discriminate mode.

Then, continue bobbing the search coil towards-and-away from the ground and gently increase the GB control towards the '+' and as soon as the audio 'beep' is eliminated on the uplift .. STOP! You now have "Power Balanced" the detector for a peak-performance GB adjustment in the silent-search Discriminate mode.

CAUTIONS: I suggest a person be able to understand manual Ground Balance and make a 'proper' adjustment in a normal fashion in the Threshold-based All Metal mode. If learning how to achieve a proper GB is too difficult for some to learn in the regular manner, then it might be even more difficult for them to get a grasp on the concept of 'Power Balancing' in a silent-search Discriminate mode.

There can be trade-offs to remember, too, such a being sure you 'Power Balance' over some of the more mineralized ground in the areas you normally search. Also, keep in mind that once you have adjusted this way in the Discriminate mode, and if you are in a higher mineralized environment, the result is an All Metal mode that will then have a negative Ground Balance. If you only search in the Discriminate mode that can be okay, but if you switch to All Metal, or the Threshold All Metal Pinpoint mode, you could have some difficulties working it with a too negative Ground Balance.

This is one reason I usually prefer to use a model that allows a manual GB, like my Bandido trio, so I can fine-tune the adjustment as needed for the search mode of choice and for the particular site I am hunting. On my 'preset' GB models, the two Silver Sabre's, I use a compromised GB setting so that it is sufficient for both search modes in most typical ground environments I hunt, and that I do not lose detection performance on larger-size silver coins, such as halves and dollars.

Monte

 

[MarkCZ]

Seems some people have reasons for "SLIGHTLY" positive or "SLIGHTLY" negative ground balancing. I had saved the below from a field test read that I found interesting, its a copy and paste and so you can look at the information and take it for what its worth.

FIELD TEST (Larry Cissna)

First off, I will give instructions on how I set up my Tejón for relic hunting. This can also be used for coin shooting.

1) First thing is to set the ground balance. This is crucial to get maximum performance. I hold the coil out in front of me off the ground 3 feet. Turn the DISC LEVEL knob to ALL METAL on the dial marker (it will click in place). Turn the threshold knob clockwise until you get a slight hum. Once I get a slight hum in the threshold, I lower the coil to the ground. The object here is to get a very slight rise in the hum as you lower it to the ground. The idealistic measurement you want is 2-4” above the ground. When you can lower your coil to the ground and the threshold volume begins to rise (2-4” above the ground), you’re good to go. This is set a little positive. Always try to tweak the GB and get the rise in hum (threshold audio) as close to the ground as possible.

2) I set my threshold at about the 1 o’clock position. This gives me a good sound when I go to pinpoint. The Tejón is a strong detector. I find turning the threshold past 1 o’clock to be too loud.

3) Switch back (click up) to the Discriminate Mode. Turn the sensitivity control clockwise until you hear chattering. Once you hear this chattering, back off a hair until the chatter stops. I suggest slowly backing off the sensitivity in order to get the proper setting. At this setting, you’re maxed for hunting in quiet mode. Beyond this setting, you will encounter chatter.

Mark

 

[Frank in NH]

Mark you have Larry's ground balancing method, how does he set his discrimination?

 

[KennyD]

Thank you very much for your responses guys....
I understand it now!!!

 

[Rick N. MI]

I don't have any problem ground balancing in disc in my mild ground. I gain a lot of depth but it is very negative in all metal. Still that's the way I use mine.

Rick

 

[KennyD]

I've never tried balancing in disc mode. I'm sure going to now!

 

[88junior]

Mark you have Larry's ground balancing method, how does he set his discrimination?

Frank he told me he sets it to knock out a small nail in disc 1 and he never uses disc 2 cause he's relic hunter.