By Steve Herschbach
Availability mid-November. MSRP $599.95 (MAP $549.90)
White's MX7 Owner's Manual
White's MX7 information page
13.8 kHz, 3.6 lbs, 9.5" concentric coil (compatible with existing MX Sport coils). Six preset programs (Coin and Jewelry, All-Metal, Beach, Prospecting, Relic, and High Trash) and easy-to-access Threshold, Gain, Ground Balance, and Pinpoint modes. Pressing the Options button accesses more controls, with user-adjustable Volume, Threshold, Depth Units, Backlight Level, Frequency Shift, Salt Track, Program, Self-Adjusting Threshold, Iron Grunt, VCO, Reject Volume, and Discrimination Mask. IP 54 rated - dust and water-resistant.
Images - click or double-click for larger versions...
White's MX7 metal detector
White's MX7 control panel
White's MX7 coil connection / waterproof speaker
White's MX7 headphone connection
White's MX7 Specifications (click to enlarge)
By Mike Hillis
You don't see much about this one.....This is something I posted on Findmall. Still haven't got to use it in minerals yet. Its almost like my free time went up in smoke this summer and fall. I got some time off for Christmas and hopefully I'll get the chance to use it in black sand minerals and see how the tracking does in a more challaging environment. Anyway...maybe someone will find it useful........................................................
Finally got to sneak some time in and try out my new Sierra Gold Trac (SGT). I went looking for something like this for use as a cleanup unit for some of my jewelry sites (and if I was lucky with my time, even some real prospecting). I was looking for something in higher frequency than what was being offered in the new Fisher/Teknetics or Minelab Xterra products. I looked at both the GMZ and the SGT. I picked the SGT over the GMZ because of the threshold control.
Right after I purchased it I got buyers remorse and put it up for sale, mostly because I didn't have any free time to do more than look at it occasionally. I think Ive had it three months now before I could actually work in an hour of actual me time to use it.
White's Sierra Gold Trac SGT metal detector
The SGT is a 48 kHz, all metal prospecting unit with only two controls; Gain and Threshold. Ground balance is handled by an Auto Ground Tracking feature that is advertised to come right off the GMT. The stock coil is a 6x10 DD. When I was talking to Jim S. about it he told me it was just a basic stripped down GMT.
Now I didn't take it prospecting or try it out in minerals yet as I was only able to sneak away from home and duty for an hour while my beloved was taking a nap. So I took it to a close by wood chip tot lot just to get to swing it and fool around with it, you know what I mean? I should say that the woodchips are not mineralized but the ground the wood chips sit upon is mineralized so there is some mineral for the SGT to track to. However the mineral strength varied depending on the wood chip depth.
The detector feels good on the arm and swings nice. I could use a little longer lower rod to make it a perfect fit but it was ok. I put the Gain on 7 and raised the Threshold until I got nice quiet hum, pumped the coil a few times until the threshold hum evened out and started sweeping.
The SGT has a VCO audio response; shallow or larger objects produce a high pitch squeal and the deeper or smaller objects produce a lower pitch tone. No, it doesn't have tone id. That is just a botched website design that is picking up some of the SST information. But the VCO tone pitch variation is helpful in sizing and depth guestimations.
As with most all-metal operating modes, smaller targets give a good zip and larger targets give a larger tonal sound. I didn't find it difficult identifying large metal objects because of this. The preset SAT is acceptable. The retune speed isn't super fast but it isn't super slow either so you have a little time to slow down and size objects before the threshold returns to normal and I didn't observe any noticeable overshoot nulling going on.
I did see the auto ground trac feature tracking out targets. The first sweep would give a crisp audio report, the back sweep would give a good audio report and multiple passes after that would tend to degrade the audio information significantly. This was super easy to circumvent though. When I hit a target I'd give it a nice triple sweep to pinpoint it under the best part of the coil, then just place the coil off to the side, do a quick double pump to bring the auto track setting back to ground and then move back over the target. That gave me enough time to not only get another couple of good audio feedback sweeps in but also enough time to do the pinpoint wiggle with the toe of the coil to pinpoint with. If for some reason I wasn't happy, I'd move the coil off to the side and double pump the tracking back to ground and have another go at it. Wasn't really a big deal after I got going and understood what was happening. And I didn't get very many targets to track completely out but I could get them to the point of a very degraded, crappy sounding signal.
Toward the end of my time out I was experimenting with the tracking out responses to see if I could get it to track out on the small ferrous like the little staples I was recovering while keeping the non-ferrous with a better audio however I didn't have enough time to make a significant determination about it and I'll continue to experiment with it.
The adjustable threshold control was a bonus as I hunted with it a little at minimum setting (totally quiet) and a little time with it maxed out as well as at the normal light hum setting. I think there is some functionality there between the threshold control and the auto track target tracking that could be useful. I'll need some more time on it to see and that hasn't happened yet.
Overall I enjoyed hunting with it. I will say a magnet stick is a must have as all the little ferrous will give a good signal and since there is no discrimination, that little staple has to be recovered. I just stuck a magnet into the end of my scoop and when I got a good zip, I used the magnet first, and if the magnet did not retrieve it I knew I had a non-ferrous object.
I didn't find anything to be excited about during this hour, other than the fact I got out and found I liked the Sierra Gold Trac and I'm not in such a hurry to part with it now that I've used it.
There was some things that I had trouble with. First the coil connector was fouled and I had to clean the threads to get the coil to connect properly. The first few times I tried to connect the coil to the box it wanted to cross thread so I suspect it was cross threaded at the factory. I cleaned that up so that it threads perfectly now. The second issue was that the coil seal is inconsistent on my coil. There are about three gaps in the coil seal that will allow this coil to suck water. I'll have to send this coil back to Whites for a replacement.
Now I just need more free me time to hunt with it some more. Now that I got a little understanding I want to use it in more minerals.
Until next time (read next year maybe if Im lucky),
By Steve Herschbach
White's is finally getting serious about giving the other guys some decent competition in the low end of the marketplace. I think it is safe to say the Prizm series never had much impact. The new units are running in the classic coin detector frequency range of 7.8 kHz so they have no serious application as nugget detectors but will be of interest for those looking for a good entry level machine. Nice and light at only 3 lbs running off only two AA batteries and a big easy to see screen. And kind of fun that they resurrected the old Treasuremaster name. I am tired of detector names that are either three letters or something that sounds like a jet fighter.
Looks like I personally have to wait for White's to do something to really get my attention but at least this is a start perhaps of a new direction for the company. Rumors of a PI/hybrid by year end?
White's Electronics Treasuremaster
White's Electronics Treasuremaster Pro
I stumbled across this Paper by Minelab discussing metal detecting basics and theory, I found it a very worthwhile and informative read, no doubt a lot of people have seen it before but like myself there are possibly many who have missed it. It holds a wealth of information about detectors and how they work.
Here is Minelab's speal about it
The following paper is both informative and helpful for metal detector users with an interest in technology. This article offers an insight into the basic theory and electronics of metal detectors.
Whilst a technical paper, this is not a formal “scientific paper” and the language used is deliberately more “reader friendly.”
Additionally, some terms are used loosely. For example; the terms “magnetic soils” or “mineralised soils” indicates soil that contains materials with significant magnetic permeability (or susceptibility).
Minelab spends a higher percentage of annual revenue in research and development than any of our competitors. We, as the engineering team, appreciate that our company supports this approach allowing the freedom to dream of what might be and act upon that vision. The result of this effort is demonstrated in the break-through technologies that Minelab has incorporated its world class detectors.
A basic approach to creating a superior metal detector includes:
1. Products that offer the most useful features and best possible performance
2. Products that are highly reliable
3. Products that exceed expectations every time they are used.
To achieve these goals we must know advanced detector theory intimately. A sound working knowledge of electronics, mathematics, and mechanical engineering are essential as is familiarity with government regulations. We also pride ourselves on our practical knowledge of hands-on detecting in the field.
This paper will give you a basic overview of the subject and some insight into the way we at Minelab approach the challenges of creating the world’s finest metal detectors.