Tesoro Cortes

Funforme

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Apr 23, 2021
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34
Anyone still hunting with a Tesoro Cortes?

I have had four or five of them over the years. Bought a closet queen last spring so I would have a TID model for my Cleansweep coil. I think all of them have had nickel id numbers in the 30's, which I like. Except for this one. It's nickel id is in the low twenties.

Not really fond of a Cortes that Id's nickels in the twenties. But...the Disc ground balance is way to high so maybe that is influencing the nickel Id. Too high of a Disc ground balance is a common failing of Tesoro models with preset ground balance settings in Disc mode. Anyway, my Cortes can't really detect a silver dollar due to the GB setting.

I'vd bean meaning to reset the ground balance point but just haven't had the time to crack it open and adjust it. Would probably adjust it so I get 12" on a silver dollar and 9" on a dime and leave it like that.

But I have also been thinking about tying it off to the Manual ground balance pot, just put a switch in place to move the ground balance dial between all metal and disc mode, maybe tie it to the mode switch.

I had it out about a month ago with the Cleansweep coil and it did ok. I could get the disc down far enough for the little gold I sometimes go after and hit quarters as deep as the cleansweep coil supports.

Anyway....thought I would talk about it a little and see if anyone else still hunts one.

Good luck!
 
AT LAST! A non-Minelab, non Nox, equipment thread!

I don't have a Cortes but I do have a Bandido and a Silver Sabre, both uMax versions. The Bandido seems to pull more good stuff out of the ground than the SS. I like Tesoro, and I'll be reading the posts as they come in. I want to learn all I can about these great detectors, whether the company that made them still exists or not. I may sell both my little Tesoros and get me a BIG Tesoro eventually. So, consider this a window shopping experience for me...
 
I read on another MD forum that one of the VDI Tesoro machines weren't designed for certain types of soil. I don't recall what kind of soils or the machine (either Cortes or DeLeon, I think), but basically someone confirmed that Tesoro did not design the machine for all soils and that in certain commonly found conditions (clay on the east coast come to mind, but again, not sure), the Tesoro detector would not do very well.

I briefly looked for that thread, but can't find it. I remember some arguments breaking out b/c some people were incredulous to the fact that this higher-end Tesoro machine could not handle a commonly found type of soil. It was finally settled when either a Tesoro employee or someone cut and pasted an email response confirming the Tesoro MD's limitation in certain types of soils.
 
Its just a ground balance setting that determines what ground it will perform best on. It doesn't become an issue unless your ground mineral is higher than the balance point on the detector.

As I said, its fairly common on preset models and just requires cracking the box and making a tweak. You can either power balance it in Disc or set it to the common ground in your area. In my case, I'm going to start out adjusting it for a desired high conductor depth response. Since I am mostly just going to use it on a Cleansweep coil, that is good enough for me.

I've had to do the same thing to all the Tesoro's that I've owned that had a preset ground balance in Disc mode.

Good luck!
 
Some people seem to place Threshold as way more important than Ground Balance as a tweakable parameter. Personally, I'll take an adjustable or tweakable GB every time if I have to make a choice. Even AUTO is "adjustable". Having a continuous tone doesn't help me discern what's in the ground better. I'd rather go just below threshold, not above. I mean JUST below. Once I know how the detector in question responds to the size of an object, and per the frequency and sensitivity that I'm working with in that detector...I should know what spirit the medium is channeling when she talks! ;-)

I've learned to accept some of the chatty boxes, like the new Simplex I've been breaking in lately. My Gold Kruzer is also chatty. I've learned to work with it, but it's got a learning curve. I can see the validity with digital machines that can offer you additional layers of "talk" but all-metal threshold in a monotone analog machine? Nope. Has not earned rite of passage. That may have been a parameter that was introduced BEFORE its time, IMO.

All this becomes especially important with today's higher frequency machines, too... 30-40 years ago detectors were mostly in the 7 -8 khz range and favored larger objects and depended on descrimination circuits more. These days you rarely find a machine under 12 or even 14 khz in the mainstream, and it seems to creeping up into the 17 - 19 realm now. Higher it gets, more sensitive to small foily pieces it is and the more chatty it gets. RELIABLY chatty. In the past, the chattiness was nothing but idle and useless and needed to be stifled. These days it should be listened to as we have the digital means to separate the syllables for easy listening.

So, in a knobby old Tesoro without digital controls?
Give me GB control over Threshold every time.
 
Funforme: said:
Anyone still hunting with a Tesoro Cortes?
Nope! I got two in (I was a Tesoro Dealer) for me and a fellow who wanted one. I took it out to several sites with four or five different search coils and had a lot of issues.

I sent it off to Tesoro, kept reminding them via phone and e-mail what the problems were, and finally got it back ... still not working well. I tweaked the internal Disc. mode GB trimmer for all the coils I had on-hand and sold it. Didn't care to have another.

Funforme: said:
I have had four or five of them over the years. Bought a closet queen last spring so I would have a TID model for my Cleansweep coil.
I didn't buy any others, but the one for my friend, and two that others had, all needed to have the Disc. mode GB trimmer adjusted for almost any of the non-standard coils. In a short time, due to those issues, visual TID they didn't like, and just not working as well s other detectors they had, they also parted with their Cortés.

I have never been fond of a 'BigFoot' or 'CleanSweep' coil, but I had one at the time I ordered in that first Cortés as the fellow wanted one for his unit. The 'CleanSweep' coil was one of several I used to evaluate that detector.

Funforme: said:
I think all of them have had nickel id numbers in the 30's, which I like. Except for this one. It's nickel id is in the low twenties.

Not really fond of a Cortes that Id's nickels in the twenties.
I wouldn't be either, but it brings up two design issues to consider. One is the internal preset GB and the other is errant tweaking of the wrong trimmer(s) to adjust for a proper Target ID setting.

Funforme: said:
But...the Disc ground balance is way to high so maybe that is influencing the nickel Id. Too high of a Disc ground balance is a common failing of Tesoro models with preset ground balance settings in Disc mode. Anyway, my Cortes can't really detect a silver dollar due to the GB setting.
And here I'll say 'Thank You' for bringing up the internal GB for the Disc. mode and alerting others to that errant setting possibly being part of the reason for the low-reading Nickel TID.

Also pointing out that being too-positive it can cause a loss of detection of high-conductive targets such as a US Silver Dollar. This is / has been an issue with a lot of Tesoro models with an improper or non-functionlng GB setting for that mode.

I've been pointing out to many Tesoro users who either have an improperly adjusted 'preset' GB model or, worse yet, they have manually-adjusted a bad GB setting.

Funforme: said:
I've bean meaning to reset the ground balance point but just haven't had the time to crack it open and adjust it. Would probably adjust it so I get 12" on a silver dollar and 9" on a dime and leave it like that.
That would be good, if you could, but often I don't see a 3" difference, at depth, between a silver Dime and Silver Dollar. More, yes, but not always a 9' Vs 12" difference.

Funforme: said:
But I have also been thinking about tying it off to the Manual ground balance pot, just put a switch in place to move the ground balance dial between all metal and disc mode, maybe tie it to the mode switch.
It could be a problem in trying to do that and have a good functional GB for the two different modes. IF I tinkered with on, I'd simply locate and external GB pot for the Disc. mode separate from All Metal. Just adjust for a proper setting for each mode used.

Funforme: said:
I had it out about a month ago with the Cleansweep coil and it did ok. I could get the disc down far enough for the little gold I sometimes go after and hit quarters as deep as the cleansweep coil supports.
It's good you could still get the Disc. that low with a too-positive GB setting, but still it wasn't always going to be 'proper' if coil changes are made.

Funforme: said:
Anyway....thought I would talk about it a little and see if anyone else still hunts one.
As I stated, No, I don't. When I took my first one out I have a Tesoro 7" Concentric, a black Shadow X2 7" Concentric, a larger 8X9 Concentric and two 10" coils of Concentric and Double-D designs.

The standard coil worked O)K, but three of the coils had a too-Negative GB and falsed a lot, and one was a bit too Positive. In order to have ALL of those coils, standard and accessory, work without falsing (by being too negative), it meant the Cortés had to be properly 'calibrated' ... meaning Ground Balanced ... so none of the coils were too Negative, but the result means one or more of the coils would end up having a too-Positive GB compared with the others.

For ANY Tesoro to perform at its best, it is good to have a proper GB for each individual search coil mounted. My favorite internally-preset GB Tesoro models, th Silver Sabre µMAX, keeps a 6" Concentric coil mounted full-time. I never change that coil because I tweaked that particular unit's GB trimmer for a very functional GB setting for some very mineralized ground in several sites I hunt.

The only model I might swap a coil on is my Bandido II µMAX because it features an external GB control which allows me to adjust the GB to be as spot-on as possible for any ground with any coil.

Monte
 
Well...Threshold is important on Tesoro detectors so I wouldn't be so quick to discount it. For instance, the Threshold control is THE sensitivity control for the All metal mode. You use the Threshold to control the depth of detection for the all metal side. It is highly likely that you will find the Sensitivity control doesn't do anything for the All Metal modes on your Tesoro models.

Also, on Tesoro, the Threshold setting affects the audio modulation in the Disc mode. It's a must have control for Tesoro, where as the ground minerals of you location determine if you really need an adjustable ground balance control.

I learned pretty early on in my dirt that I really needed a stone cold stable detector to be successful and many times that meant running really low gain settings. As my gain settings went down, the good finds in my pouch went up and I learned to balance the the gain/threshold/gb to maintain stability. If I'm stable I can hear the tiny responses that a noisy detector would hide. So I've learned to hunt all my detectors at their lower sensitivity settings, what ever it takes to have a stable unit where any response is more likely to be metal rather than EMI noise.

Good Luck!
 
Hi Monte,
Yes, I remember you are not a fan of the Cortes, for all the reason's you have mentioned. If the Cortes was a key detector for me I'd feel the same way I suppose, as you have stated, every time you switched coils you have to re-tweak the ground balance, which would force a gb modification to the unit if you really wanted to use it to its full potential, but not so hard for folks that only use the small coils, which are more forgiving of gb settings.

We didn't even bring up the other major wart which is the overshoot null in the non-motion all metal side. HA!

The CleanSweep coil is really a specialty coil for those of us who have a need for increased ground coverage, and I like the Cortes as a VDI unit for that coil.

Good Luck!
 
Metal Pig: said:
AT LAST! A non-Minelab, non Nox, equipment thread!
Refreshing, isn't it. :)

Metal Pig: said:
I don't have a Cortes but I do have a Bandido and a Silver Sabre, both uMax versions.
Congratulations! You have one of my two all-time favorite Tesoro's, the Silver Sabre microMAX. But could you qualify the other? Is it a Bandido II µMAX (microMAX) or just the µMAX Bandido? There is a big difference between the two. The Bandido II microMAX is my other all-time favorite from Tesoro.

Metal Pig: said:
The Bandido seems to pull more good stuff out of the ground than the SS.
Hard to believe if it was the first of the small-sized Bandido's, however it does make a difference on where we hunt, what coils we use, the settings used, and simply getting the coil over a good target.

Metal Pig: said:
I like Tesoro, and I'll be reading the posts as they come in. I want to learn all I can about these great detectors, whether the company that made them still exists or not. I may sell both my little Tesoros and get me a BIG Tesoro eventually. So, consider this a window shopping experience for me...
I never found a 'BIG' Tesoro that would be a better investment or performer than the Bandido II µMAX and Silver Sabre µMAX. Tesoro produced a few very good models, some so-so, and some with a design glitch, but I never really liked their attempts at a Target ID offering. I have other detectors in my personal outfit for Target ID & Tone ID.

If you have any particular Tesoro-related questions, just ask about them here, or you're welcome to shoot me an e-mail to either address below.

Monte
 
Refreshing, isn't it. :)

Congratulations! You have one of my two all-time favorite Tesoro's, the Silver Sabre microMAX. But could you qualify the other? Is it a Bandido II µMAX (microMAX) or just the µMAX Bandido? There is a big difference between the two. The Bandido II microMAX is my other all-time favorite from Tesoro.

Hard to believe if it was the first of the small-sized Bandido's, however it does make a difference on where we hunt, what coils we use, the settings used, and simply getting the coil over a good target.

I never found a 'BIG' Tesoro that would be a better investment or performer than the Bandido II µMAX and Silver Sabre µMAX. Tesoro produced a few very good models, some so-so, and some with a design glitch, but I never really liked their attempts at a Target ID offering. I have other detectors in my personal outfit for Target ID & Tone ID.

If you have any particular Tesoro-related questions, just ask about them here, or you're welcome to shoot me an e-mail to either address below.

Monte

Hello, Monte!

I like how "Tesoro talk" brings you right out of the woodwork. Actually, you and I started to talk about my Tesoros a month or so ago. I was sick and at some point I lost an entire text of a reply to you that I had spent 20min typing on my phone's little screen. I got frustrated, went to bed...and I guess I forgot to follow up. Also, I don't believe I thanked you properly for the advice you gave in our last conversation, so...thanks! :D It's seems you might be repeating some of that, but that's fine! I seriously tried a number of times to reply to you and it just wasn't working out.

It so happens I'm getting better from being sick for the 2nd time in two months, first Flu in over 4 years. Also cleaning gutters, fixing porches, working my day job...all that jazz. As a result I've only been out detecting for an hour this week, and only with my new Simplex. Nice machine for $187 in like-new in-box condition. To answer your question about the Bandido and Sabre, both of mine are NOT the "II" versions but ARE uMaxes, I've admittedly only had the SS out for one rainy, cold morning in a park. It could have been the location, sure, but I also did throw some coins down and the machine just didn't sound as strong as I would expect. My Bandido would be screaming "RIGHT HERE! DIG ME NOW!". By comparison, the Sabre was like "Hey, uhhh....this could be something good. Probably should dig it, I dunno..." That was just my impression from that one session with the Sabre. The Bandido has pulled lots of interesting things from a number of sites. No silver or gold yet, though. I live in a 1930 house in a 1920's neighborhood. I've never dug silver around my yard or the local park with any machine and I've used 4, including a Teknetics Eurotek. Plenty of clad though, but nothing much from before, say 1972. The local park is full of 1970's tabs and aluminum cans at about 4 or 5", by the way. So if that stuff is still there at that depth, where are the older coins? The park is actually a former schoolyard. The little 6-room brick school is now a rural community center as of 1974.

Anyhoo, I think the thing to do is bring both Tesoros out and run them over the same holes. That should settle it.

As far as what you said about "big" vs "small" Tesoros, you definitely put them above Vaquero, Cibola and Lobo SuperTraq? Those other machines seem to get stellar reviews from most owners...but then again, maybe they never bothered with a smaller machine so they don't know... I work with two guys who would both be interested in buying their first detector, and I might consider selling both of these Tesoros to them at a loss just to get them started. The three of us have already discussed it. I just want to make sure that Sabre isn't actually defective before I dump it on some poor sod. I got the Bandido for $300 (did I get beat?)....and I got the Sabre for $172. If I sell them I'll definitely be on the lookout for a Bandido II uMax as you suggested...or an SS2 uMax, whichever comes first. What are acceptable prices for both in good condition.

I appreciate your nut 'n' bolts posts about equipment, and you also seem quite savvy with detecting techniques, tips and tricks judging by your posts elsewhere. It seems this forum is 75% show 'n' tell, 10% Minelab and 15% everything else...so I can see why you might hide in the woodwork most of time. Right now I'm braving it all to learn any little snippets of experience or info which might help me get back into the hobby full force (I'm not fooling around this time). As soon as spring cleaning and some home improvement goals are done I'll be out detecting alot more, especially as the days get longer. I am also on TreasureNet as Pb2Au. There's apparently a bit more technical talk happening there right now than here.

Glad to see you out tonight, my man!

MP
 
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Well...Threshold is important on Tesoro detectors so I wouldn't be so quick to discount it. For instance, the Threshold control is THE sensitivity control for the All metal mode. You use the Threshold to control the depth of detection for the all metal side. It is highly likely that you will find the Sensitivity control doesn't do anything for the All Metal modes on your Tesoro models.

Also, on Tesoro, the Threshold setting affects the audio modulation in the Disc mode. It's a must have control for Tesoro, where as the ground minerals of you location determine if you really need an adjustable ground balance control.

I learned pretty early on in my dirt that I really needed a stone cold stable detector to be successful and many times that meant running really low gain settings. As my gain settings went down, the good finds in my pouch went up and I learned to balance the the gain/threshold/gb to maintain stability. If I'm stable I can hear the tiny responses that a noisy detector would hide. So I've learned to hunt all my detectors at their lower sensitivity settings, what ever it takes to have a stable unit where any response is more likely to be metal rather than EMI noise.

Good Luck!

Wow, that's some good food for thought.
To tell the truth I don't use All Metal very often except for comparing signals, troubleshooting and occasional pinpointing. I also recently learned to start my sensitivity out at about 50% or even less and go from there. I live in an area with several huge dormant coal mines. Alot of material has been churned up from the depths over the decades. I get false signals around here like nowhere else I've detected, including the beach....and by that I mean just the valley where I live. Several of the largest coal mines in the region were right here and my neighborhood was built for the miners. There are also plenty of hot rocks, real fig-sized stones that ring like coins. I'm not sure how to deal with that in a Tesoro besides maybe just lower the sensitivity even more.

As far as threshold goes, I've never heard anyone liken it to a volume control before. The way I understand it it's more of a squelch...like on a CB radio. It lets you stay just above or below the static level so that when something cuts in with any amplitude, the audio clicks on. Except in a metal detector you stay ABOVE the threshold usually and in a CB you stay under it. I'm no electronics engineer, but wouldn't that be more of an AM-induced switch? It seems to me the volume is not really under my control with threshold, its the metal in the ground controlling the volume, the threshold just tailors it so its listenable. And conversely, the discriminator would work through FM responses from different metals to whatever frequency the detector uses. So threshold and discrimination are basically adjustable AM and FM induced switches, respectively? That was my understanding of both.

It seems to me I've seen some pretty high end detectors without thresholds and people get good finds with them, or at least most people don't mention messing with thresholds much but there is still plenty of booty to show. Personally I just haven't run into any situation where I thought, "Oh no! Where's the threshold? I can't continue without a threshold." I guess I can see where it would be useful if you wanted to determine the size and shape of an object in All Metal mode, particularly when relic hunting. Is that what you mean?

If I'm still missing something, I'd like to know what it is. I'm not trying to be stubborn here. Maybe I just need to research it more.
 
More Tesoro chat ... Part 1: :)

Funforme: Yes, the Cortés was not one of my favorite Tesoro's. Actually, most of the models were not high on my list, just two or three at a time as their model line progressed. Several were in the 'No Thank You' group with the Cortés, such as the Compadre, Sidewinder µMAX, original Conquistador and a couple of others that had the Disc. mode and GB adjustment intertwined which really messed things up. An increase or decrease of the Disc. control also shifted the GB setting, and that easily resulted in a too-negative or too-positive setting.

Or were models a lot of people opened up to tweak, but not knowing what they were doing left them very messed up with many trimmers way out of a proper setting. The biggest offender there was the Compadre. Quite possibly your current Cortés also suffers from errant tweaking. Somebody opened it up and there is more than one internal trimmer. They messed with, or looked for, the Disc. mode GB trimmer and maybe trimmers needed to properly calibrate the Target ID for various US coins. I've seen that before.

Also, others might not understand, adjusting the Threshold control will have an effect on both the Threshold-based All Metal mode as well as the silent-search Discriminate mode and can be reduced from the "on-the-edge" point to calm things down and also reduce the saturated audio somewhat.

Metal Pig: While I make use of the Threshold control, keeping it adjust for a 'proper' slight-audio 'hum', the Ground Balance setting is by far the more important adjustment we can make of the two. Each manufacturer uses their own approach to GB design, and most Tesoro's were designed with the Disc. mode's GB reference a slightly positive off-set to the All Metal mode's GB setting. That was to help eliminate them from being too negative which could result in falsing if worked over more mineralized ground.

The problem is that I have often found the off-set to be too positive, especially with a preset GB model like a Silver Sabre or Golden Sabre or Conquistador, etc., so I always tweak those models for the specific coil they will always use. All manually GB'ed models, like a Bandido series or a Pantera, etc., I 'Power Balance' the GB control in the silent-search Discriminate mode for the coil in-use to have the best GB possible for that mode.

As for operating frequencies, back in the latter '70s I was using 15 kHz models the most, and when Tesoro came out with the Inca in mid-'83, I took on their product line. The Inca was 12 kHz. Most of my favorite Tesoro models operated at 10 kHz or 12 kHz. In the early '90s George Payne, a well known design engineer, wrote about why he selected 12.5 kHz as an optimum frequency for most recreational-use detectors to work well on lower-conductive gold jewelry and nickels as well as higher-conductive silver coins.

For decades now, I have relied on using a lot of detectors that operated between 10 kHz and 15 kHz. Currently, both of my Tesoro's are in that frequency range, as is my 12 kHz Nokta / Makro Simplex +. My Nokta FORS Relic is an exception I use for dense iron contaminated sites and operates at 19 kHz. Then my three Garrett Apex devices offer their Multi-Frequency, but the turn-on default frequency is 15 kHz and I often select either 10 kHz or more often 15 kHz as a single-frequency search mode.

mh9162013: It is correct that a lot of the Tesoro TID models didn't work well in a variety of ground mineral conditions. Why? Because most rely on a preset GB for the Disc. mode, and that is the most-used mode. Then, while they might have a workable GB out-of-the-box with a standard coil, the GB can be off, either way (too positive or too negative) with an accessory coil. Thus, they do not work well.

Combine that with a Target ID display that is 'segmented' rather than 'free-floating' the common targets, such as a US coin, should register in a 'proper' segment. But if the GB is off, that can cause an errant TID response. If the GB is off in challenging ground, that can also throw the TID off. Then there are other problems. :(

A coil change can alter the GB, thus causing bad behavior. Include things like the TID's being older / earlier production there were issues with circuitry components that were not tight tolerances, or some component failures. Some folks didn't like the limited TID range or number of 'segments' compared with everything else available at the time.

And finally, the circuity design sometimes had too many internal trimmers that had to be tweaked 'just right' in order to function well, but they seemed to draw the attention of hobbyists who had no clue what they did but felt they needed adjustment. The result was a detector with TID settings that were way out-of-whack so that meant bad visual Target ID.

Other things I'd like to share:

• i suggest not using accessory coils on models unless they offer manual adjustment to properly 'calibrate' the coil and detector with a functioning Ground Balance.

• Always check a Tesoro w/preset GB prior to buying it to make sure it works well, especially in the Disc. mode. Two ways to check the Disc. mode GB setting:

1.. Set the Sensitivity as high as possible, and the Discrimination at minimum. Position yourself over some black asphalt, such as in a parking lot. Bob the search coil from about 6" to ½" several times and listen to the audio on the uplift away from the ground. If you get an audible 'Beep' as the coil is lifted away from the ground, that's an indication the Disc. mode's GB is too negative.

2.. Use a US Silver Dollar or similar-size, larger 1-Ounce f Silver, such as a 'Silver Round'. Wave it passed the coil's center-axis at about 3" to 4". If you do NOT get a response, the GB is set way too positive.


** Either of these is an indication the detector was improperly calibrated at the factor .. OR .. that the detector doesn't have a stock search coil mounted. In either case, it the detector needs to be properly calibrated for a 'proper' GB setting.

Another 'heads-up' is that it could indicate that someone, or more than one, has been inside the control housing and and tweaked that trimmer for GB, which also means that other trimmers may have been adjusted which could effect a model's Tone ID or visual Target ID or other function, such as with a DeLeón or Cortés. The Compadre models have frequently been very mis-adjusted as I have encountered many of them on trades or purchases, or for others with performance issues.

• Consumers should learn the meaning of the Discrimination designs they use, such as ED-120 or ED-180, or a few that are ED-160 or ED-165.

The Tesoro brand was well-known for producing some very efficient models through the years that performed very well for many tasks. That's why I have maintained at least two Tesoro's in my Detector Outfit since July of '83. But they have also made a lot I personally wouldn't care to own for various reasons.

Monte
 
Tesoro's Bandido and Silver Sabre 'series' ... Part 2: :)

Sorry my last post, or most of them, get a little long. Bad eyes, old, and I types with one finger per hand. The last one took hours with periodic breaks.

Okay, but quickly, for me, let me discuss the Bandido 'series' which had 4 models, and the Silver Sabre 'series' which also had 4 models.

In July of '83 Tesoro introduce their first popular slow-motion, silent-search model, the Inca, that featured a Quick-Response and Fast-Recovery. It immediately grabbed my attention because I was looking for a so-called 2-Filter model with those features for hunting very iron littered ghost towns, or working through urban renovation sites or long-vacant lots where houses once stood.

I started detecting when I built my first Metal / Mineral Locator in March of '65, used home-built units until the summer of '68 when I got my first factory-produced detector in-hand. I mainly hunted the very, very plentiful city parks, schools, easements and anywhere I could, then worked my first ghost town the start of My of '69. What we had worked, but didn't work terrific. I went to VLF/ TR-Disc. models in '77 and favored them over the fast-sweep or so-called 4-Filter offerings, but the Inca made an immediate change in my direction.

I hunted a lot, but with the Inca I changed to working ghost towns and other old-use locations about 85% of the time. The Inca operated t 12 kHz, came with an 8" Concentric coil, and featured a manual GB control for the All Metal mode, and the silent-search Disc. mode worked off the GB setting with a slightly positive offset. Within 24 hours I swapped to the 7" Concentric coil off my Mayan.

In the fall of '83 Tesoro introduced their first Silver Sabre that was in a smaller-size housing and was simply based on the Inca's Discriminate circuitry. I added one of those to my outfit right-away, also, to have a constant-carry detector that was light-weight and easy to grab for tot-lots and quick-hits of sidewalk repair, etc. It came standard with a 7" Concentric coil which ws great! I hunted dense trash and confined brushy areas.

The Four Tesoro Silver Sabre’s:

The ‘original’ SILVER SABRE was introduced in late 1983. It utilized the now-popular ‘S’ rod design and was powered by 6-AA batteries. It operated at 12 kHz and came supplied with a 7”concentric coil. The control housing was metal, and was positioned under the rod just ahead of the foam hand grip, placing the controls at finger-tip reach. They had a larger speaker than used today and emitted a strong audio response. The headphone jack was positioned on the front-center of the control housing in a sloped section of metal so as to face somewhat downward.

It had one toggle which allowed the operator to select between two motion-based modes, Discrimination and All Metal. This was not a conventional, threshold-based All Metal mode, but essentially a motion discriminate mode with only enough rejection to ignore most ground mineral and respond to any metal target, ferrous or non-ferrous. Additionally, there were two variable control knobs to set the Sensitivity and Discrimination levels.

This model was the first of their successful silent-search Discriminators in a turn-on-and-go design. That is, you didn’t need to manually adjust the Ground Balance setting as it was already preset at the factory. Also, the Tesoro approach was based on a so-called 2-Filter, slow-motion design which meant whipping the coil was not necessary. The slow-sweep, quick-response and fast-recovery allowed you to pinpoint in the Disc. mode, which was all the ‘original’ model offered.

In August of 1986 Tesoro brought out the SILVER SABRE PLUS which used the same physical control housing. It also operated at 12 kHz. This model introduced a new rod-tip isolator design, and it came equipped with a white, thin-profile, open-center 8” coil. It had new electronics over the ‘original’ and now a Threshold-based All Metal mode was part of the design. That made it handier for pinpointing, as well as for sizing and shaping a target. You could also search in that mode, if desired.

Additionally, there was access that allowed you to get to the internal Threshold trimmer and Ground Balance trimmer. There was a little added depth, mainly due to the 8” coil, but the ability to have a true All Metal mode was well received. It also had the two controls to set the Sensitivity and Discriminate levels. Personally, I didn’t like most of the Silver Sabre Plus models, even though I was a dealer, because the trimmer adjustments were too touchy for the more mineralized ground I often hunted.

Another thing both of these models had in common was that they used a range of discrimination adjustment that was similar to what many manufacturers used. That is, even when at the minimum Disc. setting they were still well above Iron Nail rejection and knocked out quite a bit of small foil and even some thin gold jewelry.

In 1991 Tesoro introduced what I feel was then the best of the Silver Sabre series for hunting Iron trashed sites. It was the SILVER SABRE II and it was housed in the brown ABS plastic housing. Operating at 10 kHz, this model was supplied with the slightly thicker brown 8” open-center coil. Tesoro switched from the 6-AA battery pack to using two 9-V batteries. It also featured both a traditional, Threshold-based All Metal mode and Tesoro’s now popular slow-motion, silent-search Discriminate mode.

The control face retained the single toggle switch to select the operating mode, a variable Sensitivity control and Discriminate control, and a better positioned headphone jack that didn’t face the dirt or wet grass when you set the detector down. There was easier control of the Threshold setting by way of a tiny knob which protruded through a hole on the back of the control housing. This knob adjusted the Threshold audio trimmer on the circuit board.

Now, for the bad and the good points. For those who didn’t use headphones and relied on the internal speaker, Tesoro had switched to a smaller speaker which was more compact and lighter in weight. But the result was a much softer or quieter audio response compared with the two former models in this series. Fortunately, most savvy detectorists prefer good quality headphones.

Now the good news, and this is what made that model the best of the first three Silver Sabre offerings. Tesoro used an improved discrimination circuitry, which they introduced with the Bandido about a year earlier, and they coined the term “ED-120 Discrimination.”

Prior to the ED-120 Disc. circuitry, the Tesoro models had more rejection at their minimum setting. The “120” references the approximate number of degrees (120°) (viewed from the right) of the full acceptance portion of the sine wave (180°), while prior models only accepted about 100°± of that arc which includes the higher conductive targets and has more rejection of the lower-end non-ferrous range as well as Iron.

The result of having more acceptance and less rejection means that you improve the responsiveness on thin, low-conductive gold jewelry, and since there is less bias toward rejected Iron it eliminates some of the masking issues in Iron littered sites.

Trust me on this, the Silver Sabre II was the best of the Silver Sabre series at that time for hunting trashy ghost towns and renovation sites, especially when equipped with a smaller coil such as the 7” concentric.

The 4th and final model in the Silver Sabre series was the SILVER SABRE µMAX which was released in October of 1997. Like the Silver Sabre II it still, operated at 10 kHz, and it still was powered by a 9V battery, but this time it only required 1-9V battery. The new µMAX (pronounced microMAX, not You MAX)) used the same small housing that was first used for the Target ID display of their Toltec II, then for the Sidewinder series. This small, top-mounted housing used small, surface-mount technology that was admired by many for its light, handy feel.

This model had three variable controls on the front panel. One for Sensitivity, one for Discrimination, and one for Threshold adjustment. It no longer had a toggle to select an All Metal search mode because few people hunted in that mode which was primarily used for pinpointing a target. Instead, Tesoro added a big, easy-to-activate push button that momentarily switched to a static all metal Pinpoint mode.

One thing Tesoro had lacked was a little extra depth and audio response from those targets that were typically in the mid-depth to deeper range of detection. Tesoro addressed this by incorporating their “Low-Noise / High-Gain” circuitry. The result was much better depth, and audio response on targets in that detection range, and it saturated the audio more as well.

The trade-off, however, was that this new circuitry worked really well in Iron free areas, but they had a little difficulty in sites with a dense littering of Iron Nails and other smaller Iron where the Silver Sabre II had a 'slight' edge.. The Silver Sabre µMAX still used the very good ED-120 Discrimination concept, but was a little noisier when hunting in Iron trash.

As for which of the four Silver Sabre models was the best, I’ll have to say two of them were. Personally, I had great success with the Silver Sabre II when I hunted my favorite ghost towns, but most often I was using the 'original' Bandido or Bandido II. They had the same ED-120 Disc. circuitry as the Silver Sabre II and I preferred / prefer to have manual GB control, but that discrimination helped find a lot of good coins and trade tokens and buttons at a site where they had been otherwise masked with earlier Tesoro models.

My all-time favorite, as I look back on them, is the Silver Sabre µMAX for most hunting I do. Light, handy, quick-use PP button, and I preferred the potentiometer to adjust the Threshold rather than the original knob-in-the-trimmer approach.


The Four Tesoro Bandido's:

Even though these models were long discontinued, they had remained in service and popular for many avid detectorists simply because they work, and can work quite well. I hope this post might be of help.

Let's first address the spelling and pronunciation of the latter model's name. Tesoro used the 'µ' symbol which is NOT a letter 'u. The 'µ' symbol is an electronic term that stands for 'Micro.' Tesoro used the term in front of the word 'MAX' to say 'µMAX,' which is pronounced 'microMAX' as a description of the micro-sized housing that provided MAXimum performance. It is not pronounced You-MAX.


The BANDIDO (original) was a replacement for the Eldorado and was a departure from the metal housing to the brown ABS control housing. It operated at 10 kHz, had a white 8" open center coil, and had four variable controls and one toggle switch. You could adjust the Sensitivity, Discriminate Level, and Threshold. Also, there was a 10-turn Ground Balance control. The Toggle was the familiar three position with the lower setting for Disc., the center for Threshold-based All Metal, and the upper a momentary spring-loaded position for retuning the All Metal mode. It had what I felt was a "comfortable" auto-tune speed for general applications.

What really set it apart from the earlier Tesoro models was that it was their first model to employ the ED-120 discriminate circuitry. This allowed the operator to adjust down lower in the discriminate range towards Iron. At the minimum setting, the ED-120 models will usually be at a point to just knock out surface nails either cleanly or with a distinguishable "tick" or "double-tick" and be very close to the ferrous / non-ferrous break-point.

The BANDIDO II is virtually the same detector, except for two visual and one audio change. Still operating at 10 kHz and in the same package, Tesoro went to the 8" open-center brown coil. You will also notice that they added a second toggle switch labeled Normal and Auto-Tune. The "Normal" setting simply means there is no auto-tune and the operator will have to manually re-tune with the other toggle switch to restore the audio Threshold. In the "Auto-Tune" setting, the re-tuning speed was increased from the comfortable Auto-Tune speed in All Metal of the original model. This was to appeal to those who used the Bandido's for Nugget Hunting.

Personally, I preferred the original Bandido as the white coil was lighter weight and less tiring, and I thought the auto-tune speed was just fine. The Bandido II, however, was also a super performer for me in the Iron Nail infested western ghost towns I enjoy searching.

If you scan the older literature to the present, you'll see that every Bandido model has been touted as being good for relic, coin and nugget hunting. Even though they've claimed it as a "nugget hunting" tool they erred with the introduction of the Bandido MicroMax.

The third model in the series was the µMAX BANDIDO. It was supposed to be an 'updated' model using the small-size microMAX housing and going from a two 9-V battery power to a single 9-V battery. Don't let the performance of most of the small 'microMAX' packaged models fool you. They will perform! But with the third version µMAX Bandido, which was based on the µMAX Sidewinder, the operating frequency was increased to 12 kHz, which was fine, but one control adjustment was omitted. A Threshold control.

Since most searches are made in the silent-search Disc. mode, that's no big deal for most Coin Hunting hobbyists, but for a detector that is touted as being a "universal" type, and one intended for the Relic Hunter or Gold Nugget Hunter, who will often search in the Threshold-based All Metal mode, having control of the Threshold setting is very important.

Additionally, they made one other change and that was to go from a 10-Turn Ground Balance control to a 3¾-Turn control. Certainly this would appear to have less range and less fine-tuning ability as compared to the 10-Turn type.

Honestly, I would bet that most hobbyists would be just as well served by the µMAX Bandido as with the two earlier versions that had the Threshold control. Still, there were enough of us who preferred to have more control over the unit and wanted a manual Threshold control and Tesoro apparently listened. They also listened to those who had complained about the quick drop-off in audio with depth (loss of depth and an abrupt modulated audio of what was there) and hoped for better deep-target signal response.

The fourth and final entry in the Bandido series is the BANDIDO II µMAX. Note that they moved the 'µMAX' name to the back-end of the nme. This unit was back down at 10 kHz and is quite different than any of the earlier Bandido models. Externally it now featured a Threshold knob on the control panel, and I like that

However, they have gone to what they call a "low-noise, high-gain" circuit that I like as it will either go deeper, or you will perceive better depth because the audio response is saturated out on deeper targets than the earlier Tesoro models. With the added depth and louder response you have a trade-off however. The newest Bandido II MicroMax does NOT handle the sites with an abundance of surface nails as well as the earlier Bandido models.

They still have their noted "quick response" and that lets them work well at sites where there are a lot of targets and you can pick out partially-masked near-by targets quite well. There is something in the "low-noise" filtering that creates a condition I refer to as "shut-down" and they do not handle good targets among Iron Nail trash as well as the former discriminate design.

There is absolutely nothing wrong with the µMAX Bandido. I had one that I felt was "hot" and it worked quite well. But the Bandido II µMAX is also a fine detector that became my favorite for most applications. It is because they incorporated the new 'Low-Noise' / 'High-Gain' circuitry. The result? Much improved depth-of-detection and more saturated audio within that enhanced depth range than the former models.

So, there you have it. There are the 4 Bandido series models as they progressed.. They are all good detectors, you just have to tailor your selection to suit your applications and budget since the newest model has jumped up to a more demanding price.

If you have any questions, please feel welcome to e-mail me directly and we'll discuss the Silver Sabre or Bandido models of interest. For me, I keep one of each of the final versions in my personal-use outfit. The Bandido II µMAX and Silver Sabre µMAX. (Note: There was no Silver Sabre II µMAX.)

I hope this is of some help or interest to someone.

Monte
 

mh9162013: It is correct that a lot of the Tesoro TID models didn't work well in a variety of ground mineral conditions. Why? Because most rely on a preset GB for the Disc. mode, and that is the most-used mode. Then, while they might have a workable GB out-of-the-box with a standard coil, the GB can be off, either way (too positive or too negative) with an accessory coil. Thus, they do not work well.

Combine that with a Target ID display that is 'segmented' rather than 'free-floating' the common targets, such as a US coin, should register in a 'proper' segment. But if the GB is off, that can cause an errant TID response. If the GB is off in challenging ground, that can also throw the TID off. Then there are other problems. :(

A coil change can alter the GB, thus causing bad behavior. Include things like the TID's being older / earlier production there were issues with circuitry components that were not tight tolerances, or some component failures. Some folks didn't like the limited TID range or number of 'segments' compared with everything else available at the time.

And finally, the circuity design sometimes had too many internal trimmers that had to be tweaked 'just right' in order to function well, but they seemed to draw the attention of hobbyists who had no clue what they did but felt they needed adjustment. The result was a detector with TID settings that were way out-of-whack so that meant bad visual Target ID.



But the Cortes has adjustable GB. Wouldn't that remedy the GB issue with certain soils or coils?
 
mh9162013: said:
But the Cortes has adjustable GB. Wouldn't that remedy the GB issue with certain soils or coils?
No, because as I related, the Cortés only has an external GB control that functions with the Threshold-based All Metal mode. The silent-search Discriminate mode relies on a properly-set internal GB trimmer. There's the problem with coil changes. That blasted GB trimmer is inside with other trim-pots and not easily user accessible.

Besides, a lot of people today don't have a clue what Ground Balance is, what effect some settings might have on a detector or performance, and when a control is available, many haven't got a clue how to adjust it.

Monte
 
PS: There are a lot of popularly used detectors on the market today or in use for a dozen years or more that rely on a factory preset GB for the Disc. mode even though they have manual GB or even auto-mated GB functions. Even some with manual GB do not allow the operator to adjust them to an extreme to be too negative or too positive because the Disc. mode is controlled / preset.
 
No, because as I related, the Cortés only has an external GB control that functions with the Threshold-based All Metal mode. The silent-search Discriminate mode relies on a properly-set internal GB trimmer. There's the problem with coil changes. That blasted GB trimmer is inside with other trim-pots and not easily user accessible.

Besides, a lot of people today don't have a clue what Ground Balance is, what effect some settings might have on a detector or performance, and when a control is available, many haven't got a clue how to adjust it.

Monte

That applies to me, at least to some extent. I've done some research online about it, but I'm not 100% sure I'm getting the whole picture.

I understand that having the wrong GB means:

a) the metal detector may have reduced sensitivity which effectively means it's not detecting as deep (or as small targets) as it could otherwise;

b) the metal detector is so chatty, that the user will miss good targets due to sensory overload or notching out (whether with the metal detector itself or by using their own ears); and/or

c) the VDI on the metal detector will be off, such as reading iron as foil, pennies as dimes, etc.

Is there anything else I'm missing?
 
mh9162013: said:
That applies to me, at least to some extent. I've done some research online about it, but I'm not 100% sure I'm getting the whole picture.
Okay, maybe to help more I'll ask you this:

What detector makes and models do you own and use?

What, to your knowledge, type of GB do they have?

mh9162013: said:
I understand that having the wrong GB means:

a) the metal detector may have reduced sensitivity which effectively means it's not detecting as deep (or as small targets) as it could otherwise;
It is possible that a very improper GB setting could cause some problems with desired target detection. It depends on the make and model detector, but if it is too negative, you can get a lot of false signals from search coil variances from a proper coil-to-ground relationship (which should be ±2") and that means sweeping over more mineralized rocks, or less mineralized rocks, or over a hole or void can cause noisy behavior.

To correct it requires a proper GB setting, but some folks will reduce the Sensitivity to try and deal with the noise and that, naturally, can reduce depth and small-target detection. They might also increase the Discrimination, well past that of handling the ground mineral signal, and that can also reduce depth and performance.

mh9162013: said:
b) the metal detector is so chatty, that the user will miss good targets due to sensory overload or notching out (whether with the metal detector itself or by using their own ears); and/or ...
See my reply above.

mh9162013: said:
c) the VDI on the metal detector will be off, such as reading iron as foil, pennies as dimes, etc.
Yes, if the GB for the Discriminate search mode is too far off from 'proper' you can have a significant loss in performance. Things like no detectable response from a big Silver Dollar, and in some cases it can be so positive that your detector might not produce an audible response on a half-dollar, a quarter, and there have been times I have seen them not even respond audibly to a dime, just from being way too positive.

mh9162013: said:
Is there anything else I'm missing?
Just remember that the primary purpose of a Ground Balance control is to adjust a detector just to the point where it will balance or cancel or neutralize the ground mineral signal. That's what you want to help eliminate noise and to process a cleaner signal from a located metal object.

Monte
 
Monte, I wish I could buy you lunch for all you bothered to write. Do have a few more questions regarding this and that, but I owe so off to work I go! I'll be back. Thanks!

MP
 
Thanks Monte, those are very helpful answers and confirm the "gist" of my understanding of GB, although you corrected or added to certain points of my understanding.

Okay, maybe to help more I'll ask you this:

What detector makes and models do you own and use?

What, to your knowledge, type of GB do they have?

I have a Fisher F2, Vanquish 340 and Vanquish 540 - none have real GB adjustability.

I know the 540 has the "poor man's GB" trick of just notching out 1, 2 or 3 "ticks" on the lower end of the discrimination segment bar. And that definitely helps the "chatter" coming from hot soil.

But I think my ground is about 1-5 inches of somewhat mild soil, then anything deeper I hit orange clay that's fairly mineralized...enough that it'll cause my Garrett Carrot to give off a moderate "beep-beep-beep" on max sensitivity (unless I turn it on while the tip is touching the clay).

I'm wondering if I had an adjustable GB, if that would help my machines handles this clay. If the answer is yes, by how much and in what way. And depending on those answers, I may start saving up for an Equinox 600 b/c I think areas in my neighborhood have silver coins that are in or just below the mild soil, but on top or just above the clay layer.
 
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