Tesoro Lobo Super-trac Alignment Procedure?

[Az_Ed]

I'm helping an Arizona Archaeologist search for artifacts.  The favorite detector used is the Tesoro Lobo Super-trac since it is simply a turn-on and go detector.  Nearly any volunteer on the project can grab the Super-trac and be productive.  I am refurbishing some of the failed detectors.  Does anyone have an alignment procedure for the Super-trac?  I notice about 6 potentiometers (variable resistors) on the PC board and I'm wondering if alignment checks might be useful.  Thanks for any help.  Ed, Tucson, Az.

[Steve Herschbach]

Unless you know exactly what you are doing touching those potentiometers is an excellent way of screwing the detector up. They were set properly at the factory, and hopefully have been left the way they were ever since. I’ve known people who messed with the settings to make the machine hotter in some situation, only to find that there is no free lunch, and it hurt the performance in other ways. My advice is leave well enough alone unless you have direct access to and knowledge of the factory tuning procedure.

The Lobo is not a turn on and go one knob detector and there are switches that can be set improperly. For instance, setting the discrimination too high could eliminate desired targets. Best bet is any user read and understand the operating manual.

[Geotech]

In what way have the detectors failed?

[Rick N. MI]

This is a photo of what my Lobo ST board looked like.

I turned the Ground Balance neg 20 degrees in my mild ground. Depth increased greatly. I used the 8" concentric coil.

[Az_Ed]

   Thank you for the comments Steve.  The use of the detectors is an archaeology search so everything is dug.  Thus All-Metal mode, no discrimination and the users adjust the sensitivity and threshold as-needed.  I gather the archaeologists like the Super-trac due to simpler settings and no ground balance controls.  They purchase used Super-tracs whenever found.

   I am an experienced electronic engineer and technician so working with the electronics doesn't worry me.  I know I can't make any adjustments without a procedure, schematic or something as a guide.   My primary alignment concern is the possible need to recognize a dirty or malfunctioning potentiometer.  If I had some sort of technical guideline or even a description of pot function it could help with repairs.

   So far one unit was stated to "not sound right."  It was very dirty inside with dust coating the PC board.  I cleaned the pots with DeoxIT D5 and cleaned away the dust and re-seated the socketed IC.  The speaker is glued-in and tested ok at about 16 Ohms.  New batteries and it was back in the field, but still considered to "not sound right."  I need a head-to-head comparison with a good one to see if I can hear the "not sound right" symptom.

   I have two other units, one DOA and the other unknown status.  I have not yet looked at them to see what is wrong.  Most likely something electro-mechanical like broken battery wires, etc.

   The Super-trac seems to be very good at small targets not too deep.  It is looking like the archaeology efforts need to find larger (small horse shoe) targets as deeply as possible.  I think they need larger coils.  I'm in process of evaluating coil sizes, detector models and possible depths at a test range I rigged in my back yard.  I buried a 3" OD tube at a 45 degree angle.  I'll be able to place targets up to 31" deep.  I have a series of different targets on wooden paint or yardsticks.  I plan to spreadsheet a comparison to get a feel for what is possible.

   I'm most interested to see what the Garrett Axiom with the 16x14" mono coils is able to do.

   Thanks for any suggestions or comments.  Ed. Tucson, Az

[Jeff McClendon]

I am really glad that there are university archeology departments that are willing to employ the use of metal detectors for some of their projects. That is a big improvement and helps with the negative opinion that some "professionals" have held about using metal detectors for easy metallic object recovery during university or historical society sponsored projects.

I like the Lobo Super Traqs. I owned the Lobo and the Super Traq. They are very sensitive on smaller targets from my experience and easy to use. 

However, parts availability, coil availability, weight,............there are so many comparable detectors available right now that are every bit as good or way better than the Lobo. 

I have worked with Colorado State University on a few projects.  The times that archeology students and their advisors arrived with metal detectors to help those of us that metal detect for real, those people showed up with old, beat up Bounty Hunter Tracker 4s because someone in the department had recommended that detector!  We had Equinox and Deus detectors. They found next to nothing. We (7 people) found over 400 period legitimate targets in two 8 hour days of detecting. In all, we recovered over 4000 targets during the Julesburg Project.

How would those students do with several $259 Minelab X-Terra Pros...........Just something to think about.

[Az_Ed]

   Hi Jeff,  I agree with your comments regarding the Super-trac.  I was surprised when I heard it was the preferred detector.  I'm hoping some test data may show it could be advantageous to move to a newer detector.  Detector weight is most important since a lot of back-country ground is covered in search of artifacts while walking quickly.

   An ideal detector for these efforts would have simple controls and operation in all metal mode, lightest possible weight, loud speaker, and something like a 10" elliptical coil.

   The Archeologist is independent of any university and is an advocate of using detectors to help locate sites and has done so very successfully.

   My latest Super-trac repair was a loose terminal post on one of the battery packs and a loose On/off Threshold control.

 

[Jeff McClendon]

I had to solder loose battery terminals on my Lobos too. Just part of life with a detector with old solder joints. 

[Steve Herschbach]

I used the Lobo at my pay to mine operation in Alaska for the reasons stated - easy, all metal operation. We marked the controls with presets and handed them out as loaners for people needing a detector. We also had the Infinium as the PI alternative for the same reason.

An Xterra Pro actually costs less, is waterproof, and can be had new with a warranty, and would certainly be my choice over the Lobo these days. I'd vote for the Deus though with a trained operator for an archeology department as perhaps the most successful relic recovery machine ever made. Tens of thousands of European relic hunters use the Deus for a reason.

But it keeps coming back to what do you hand a person that knows nothing about running a detector, and the Lobo is still in the running as a device there. Something like a Deus or even an Xterra would need to be set up by a knowledgeable person than handed off with a warning not to mess with the controls.

[Az_Ed]

Thank you for the comments.  The Minelab Vanquish 540 has been recommended and looks like a good fit to me.    The current cost is very reasonable (<$400 new) and it is simple.  It apparently has automatic ground balance and 4 modes.  It looks like one can turn-on, set to all metal mode, adjust the volume and sensitivity and go.  This might compare well to past Super-Traq usage.