Minelab Xt 17000

By Reginald G. Sniff
From page 18 of the September, 1993 issue of Lost Treasure
Copyright © 1993 Lost Treasure, Inc. all rights reserved


In some ways hunting for gold nuggets is like hunting for coins in the respect that there are still plenty of nuggets to be found even in the hunted out areas, but they seem to be just out of the reach of the average detector.

Fortunately for the serious nugget hunter, Minelab has just introduced their new gold detector, the XT 17000 which is designed to give him and her the edge they need in obtaining that little extra depth.

I had heard rumors about this in­strument my last trip to Arizona but hadnt seen one. Now, through the courtesy of Down Under Treasures, distributors for Minelab, I had an XT 17000 for evaluation.

Obvious from the features incor­porated in this detector, Minelab put a lot of thought process into the fea­tures of this unit. For example, one of the most critical adjustments in obtaining maximum depth is keep­ing the unit properly ground balanced. The XT 17000 has one of the best automatic ground balancing sys­tems I have ever used.

Another unique feature included is the ability to select between two different frequencies 6.4 KH and 32 KH. The 6.4 KH is designed for maximum depth on larger targets and the 32 KH for the extremely small pieces of gold.

The overall sensitivity of the in­strument can be adjusted by three different ways including an adjust­able sensitivity control. A second control, a 3-position toggle switch labeled Normal/Enhanced/Boost di­rectly affects the amplification and tone somewhat of the target. A third technique is another switch which allows the operator to select between normal and difficult ground condi­tions. This switch assists the hunter in dealing with extreme ground con­ditions which makes determining the difference between subtle ground changes and deep targets somewhat easier, especially for a less experi­enced hunter.

Also included is a volume control, which again is unique in design. In­stead of the standard technique of reducing the volume of all signals so that as the owner reduces the volume control all weaker signals are also reduced, the Minelab uses something they call volume limiting.

Volume limiting only affects the maximum limit of the signal, and not the weaker signals. This design al­lows the use of extremely sensitive earphones, which can give a good response to very weak targets but will produce an excessive volume on large shallow targets without the volume limiting.

The ground adjustment is accom­plished by selecting Ground on the 2 position control and merely pump­ing the detector coil up and down a couple of times towards the ground. Simply stated, it couldnt much sim­pler to compensate for even the most severe ground conditions. In fact, many hotrocks can be quickly ig­nored with only a few motions of the coil without the fear of tuning out most of the nuggets. (Extremely weak signals should always be investi­gated.)

Once the instrument is properly ground balanced, leaving the control on continuous balance will assure the best possible adjustment in al­most all cases. In the few instances where the continuous balancing may seem to a problem, the operator can quickly switch to the fixed position and lock the ground balance to the latest setting.

The XT 17000 also has a limited discrimination control designed to cause the audio to respond with what Minelab calls a staccato sound over ferrous objects. Instead of causing the instrument to ignore suspected targets, the sound of the target stut­ters on targets determined to he made of iron.

Minelab has included an adjust­ment to adjust the audio tone of the instrument. Found at the hack of the instrument, this control requires a small screwdriver for adjustment.

To assist in saving the owner money from continuously buying batteries, Minelab has included a standard ni-cad battery pack and charger. An optional battery holder designed to use 8 Alkaline penlight AAs is available from the factory. Also, Minelab has included a control housing cover/holder that both pro­tects the unit from the weather and allows the control housing to be hip mounted.

The XT 17000 comes standard with an 8-inch wide scan coil and soon will have an optional 10 inch elliptical coil available.

FIRST IMPRESSIONS:

After assembling, reading the manual, and making a few passes over some of my different size gold nuggets, I have to say that I am extremely impressed with the ease of use and the instruments sensitiv­ity.

My initial settings for testing of the instrument were: maximum sen­sitivity, Boost, automatic ground balance, normal ground, and the higher frequency. I figured I might as well start out by seeing how this unit responds with everything at max while looking for the smallest pos­sible targets.

Although the manual did recom­mend the lower frequency with the standard 8 inch coil, I found the depth difference negligible between the two frequencies, and, for some reason, I preferred the higher fre­quency for much of my testing and most of my subsequent hunting.

With these settings, I found I was using an instrument that really im­pressed me. The ground balancing was as simple as turning the unit on, pumping the search coil up and down a couple of times near the ground and the detector was ready to go. Once ground balanced and every­thing at maximum, the unit was sur­prisingly smooth and simple to use.

A quick pass over a couple of small nuggets only a few grains in size as well as various targets I have planted and I knew this detector also had both extreme depth capabilities on larger targets and the sensitivity to detect extremely small nuggets.

In fact, a couple of passes over my standard 9 inch deep nickel and I knew this target was too easy for this instrument. So, I opted to try the instrument over another recently buried nickel which happened to be 11 inches deep. I had planted this coin only a week or two earlier to check the absolute maximum depth of different detectors. To my sur­prise the XT 17000 picked up this target better than anything I had tried before.

One feature of this detector I didnt have much luck with was the En­hanced mode. This mode is sup­posed to alter the audio response of the target making the target easier to distinguish.

During my testing, I didnt notice much of a difference and the detec­tor didnt seem to be quite as sensi­tive as the other modes. The lack of distinction between different tones could have been the result of my hearing limitations.

I should mention again that the discrimination feature of the XT 17000 is different than most detec­tors. As mentioned before, no metal­lic target is ignored, rather, if a target is determined to be iron (ferrous), the audio response will be a staccato or stuttering signal.

During my testing I found this stuttering response to be an obvious difference in audio signals making shallow iron objects easy to identify. Deeper iron objects were often ac­cepted as good targets even with the detector set at maximum discrimina­tion depth range. In other words, I found the iron objects had to be rela­tively close to the coil for proper rejection.

Also, all non-ferrous junk typi­cal to a coin hunter such as tinfoil, pulltabs, etc., responded with a good audio tone.

Because this instrument didnt lend itself to average coin hunting because of the discrimination cir­cuitry design, I decided the only logi­cal field test was in gold country. So through some quick finagling I was able to take a weeks vacation and I headed for my favorite sites in Ari­zona.

NUGGET HUNTING IN GOLD COUNTRY:

Because I am a firm believer in obtaining permission before hunting areas under claim, I spent the better part of my first day in Arizona talk­ing to claim holders and obtaining the necessary consent. By the time I was through most of this day was gone and the key areas I wanted to hunt were too far away. So I decided to head for a nearby area where I hoped I could get in for a few min­utes.

I ended up at a site presently being worked on a percentage basis by an acquaintance of mine. Unfortunately, he wasnt there but his caretaker and hunting partner was. After a few minutes conversation and my agree­ing that anything found would re­main with the caretaker, I began checking out an area recently bull­dozed.

My initial setup of the instrument was the same that I first tried during my initial testing. The sensitivity was at max, boost was on, auto ground balance on, 32 KR frequency, discrimination at max, and the vol­ume control set for a comfortable maximum volume on my very sensi­tive earphones.

The caretaker, Charlie, informed me there wasnt much use looking since the area had been thoroughly searched a couple of times, but I was welcome to try. At first I was begin­ning to think Charlie was right since the only thing I found was several small pieces of iron.

Like my initial testing, most of these really small pieces didnt re­spond with the typical staccato sound common to ferrous objects until pieces were dug up and very close to the coil. I mention this condition again because it might concern even the best coin hunter new to gold hunting or unfamiliar with typical gold hunting instruments.

However, past experience has proven to me that this design of the discrimination circuitry is really the best since it is extremely easy to reject a nugget because of the ground conditions or hotrocks. The last thing a serious nugget hunter wants to do is ignore the only nugget they pass over.

After about an hour of looking I could see that Charlie appeared anx­ious to try the instrument, so I gave him the reins. Since he was familiar with his own Minelab FT model, he quickly pointed out the need to mount an additional mounting bracket on the shaft. The reason for the extra mounting bracket is, although the instrument is not excessively heavy, working over uneven terrain did be­come tiring with the unit conven­tionally mounted on the shaft.

The XT 17000, like other late model Minelabs, has a quick and simple means of installing or remov­ing the instrument from the shaft. On the shaft is a slender V type bracket that mates with a corresponding shaped moulded connector on the top of the control housing. To install the unit on the shaft all a person has to do is line up the unit and slide it on the bracket. The V design allows for a snug wedge fit. Adding an addi­tional bracket only requires drilling a couple of holes and pop riveting the bracket to the shaft.

Charlie, like many Minelab own­ers, has purchased the additional mounting bracket and installed it on the bottom of the shaft of his instru­ment directly below the forearm. With the control housing mounted at this location, Minelab s detector coil and control unit seem to counterbal­ance making the detector extremely comfortable even over the most vary­ing of terrain. This control housing location works well because the de­tector adjusts itself automatically, and there is little need to have the controls at your fingertips after the initial adjustments are made.

Obviously, the included body mount attachment would have also been a logical alternative at this site, and once a person was accustomed to operating an instrument in a hip mount position, it can become sec­ond nature.

However, I have never gotten ac­customed to hip mount setups be­cause I normally hunt very brushy areas where the brush can easily snag the wires dangling from the instru­ment to the shaft, and as a result I will modify this instrument with the ad­ditional bracket when I get back home.

Anyway getting back to the test­ing, after a while I took control of the instrument again and within a few minutes had a nice positive response.

I handed the instrument to Charlie and asked him to check it. He too decided that it was a good target. Several swings with my digging tool into the concrete hard ground and out popped a lump of clay with a target inside.

A quick rubbing of most of the dirt off the target and the traditional popping of the now known material into my mouth for a quick cleansing of most of the remaining clay, (tastes terrible but the results are worth it), and I had a nice gold nugget esti­mated to weigh around 40 grains in my hands. Reluctantly I relinquished the nugget to Charlie.

Later, after discussions with my acquaintance who works the claims, I agreed not to disclose the exact location of the site except to say it was in the Rich Hill area.

The next couple of days provided me with plenty of exercise, a few blisters, and lots of small pieces of trash to show for my efforts. This didnt discourage me since I know from experience no matter how good a detector I am using, there is a certain element of luck combined with persistence needed for success.

Finally on the third full day of hunting, I was on my way back to my Bronco II when I decided to make one last pass at an area not more than 50 feet from my vehicle.

After finding the usual small pieces of junk, I got a nice strong signal that seemed to ring in my ears saying here lam. Well, in a couple of minutes of digging and cleaning, I was looking at my keeper, a beau­tiful gold nugget which was later determined to weigh about 135 grains, a little more than a quarter ounce in size. Ill tell you, the sight of nuggets makes you want to kiss your machine for providing the tech­nology to recover such natural beau­ties.

The rest of the trip was only a success in the fact that I continued to learn more about the instrument. Although I didnt find any more gold, I did learn that many of the subtle responses caused by sudden changes in mineralization could be evaluated by slowly passing over the suspected area from a different position. The stratification and stringers of miner­alization could give false signals if passed across them, but by changing my direction of approach, the coil would run parallel to most of the ground changes and the false signals would disappear.

It was obvious that continued use at the gold country locations could only enhance my knowledge of this instrument. But alas, I had to return home and only dream of the next time I would get back to try the XT 17000 again.

CONCLUSION:

No instrument can assure success in the hunt for elusive gold nuggets. However, the Minelab XT 17000, with its ease of use, exceptional ground balancing capabilities, and extreme sensitivity, can mean reach­ing that extra increase in depth nec­essary for success.

I can heartily recommend this in­strument to all serious treasure hunt­ers wanting a serious nugget hunt­ing instrument. Priced at $875, the instrument comes with everything except earphones. I do recommend the purchase of the optional battery holder or an additional ni-cad bat­tery pack so one can carry a spare set of batteries at all times.

For more information on the XT 17000 or any other of the Minelab series of detectors, you can contact: Down Under Treasures P. 0. Box 91538 Henderson, NV 89009 Phone: (702) 565-1353.