By Don Barthel
Make no mistake, the new Excalibur is the best yet, with improvements that include new coils, new headphones, and a modification of the lower staff. The electronics (BBS, simultaneous 17 discrete frequencies technology) remain the same, however. Other differences include color (dark blue casing), case-to-battery fit, and sealing changes. The test seemed to start off great. Before going to Kauai, Hawaii I went to a local beach and found a lady's 14K emerald & diamond ring. Well... not quite. The “emeralds” were Mexican jade, and the baguettes were not diamonds. What at first looked like a $300+ ring suddenly plunged to about $15 in gold! At least it's marked “14K.” Right after that, I dug an 8" piece of sheet metal and promptly cut my right thumb in two places. As a result, my detecting was terminated for over a week, until I arrived in Kauai.
After several hours of operation, the new headphones developed significantly lowered volume. However, since I was in a good spot and the Excalibur was still producing, I continued hunting. Ken Davico of Kapaa, Kauai, a superb professional detectorist, had recently pointed out that his new Excalibur 1000 really shines when working the cracks in the high iron content, black lava rocks. “By hunting in 'Disc' at minimum sensitivity,” he explained, “I can pick out the gold rings and coins. My two other brands of detectors cannot.”
Although I found no gold, my coin count ($26) and other finds— five silver rings, two earrings and a silver Madonna money clip— were above average. This success came despite much more competition from locals like Dave, and the fact that there were fewer tourists to generate targets. After concluding this round of testing, I contacted Minelab, and they checked out the unit at their Tempe, Arizona facility. After another eight hours of use, the stem developed a crack and separated just above the attach point on the coil. Since I have the older model Excalibur (and a new Sovereign XS), I thought I'd just switch parts. However, I discovered that, due to redesigning, interchange ability isn't always an option. Some parts from the older models just don't fit this new one.
To Minelab's credit, changing the lower staff to one piece solves a work-loose problem that I pointed out in an earlier Excalibur field test (June '97 W&ET). Also, everything I said in that report still goes: it's a great detector! I also made the suggestion to change the Pinpoint/ Disc switch so that it can be operated with the hand holding the machine, and that's still something I'd like to see. It's hard to switch back and forth if you're carrying or dragging a large scoop, especially in the water.
The new coils are great, although they don't slide through the water quite the same as the older model SeaSearch coil does. The new Excalibur is available with either a 10" or 8" coil. The 10" coil is a definite improvement, going slightly deeper and providing greater coverage and improved sensitivity. During testing, I compared the new 8" coil (actually 7-1/2") installed on my Sovereign XS to the 10" coil on the new Excalibur. (The electronics and operating characteristics of these units are vir-tually identical.) In moderately heavy mineralized sand, both coils would detect a nickel at 10" very faintly, although response with the 10" coil was a tad louder. In my “hunting” mode, I would probably miss both signals; but with the nickel 9" deep, I would probably catch both signals. In summary, the 10" coil has a slight edge in depth and a big edge in coverage. On the other hand, the 8" is much lighter. Both are highly recommended.
One thing you'll notice about the Excalibur is its weight, due to the 200' depth rating which dictates a heavy-duty casing, a hefty battery pack, and the weighted neutral- buoyancy coils. Because of this, you'll probably prefer to use it as a hipmount out of the water. Minelab doesn't offer a hip-mount kit, but there are a few aftermarket units available. The ones I've seen involve substituting a piece of tubing for the staff and tying the resulting shorter unit around the waist. If you are going to use your Excalibur out of the water, a waist or hip mount will be a welcome addition to your equipment. However, in the water, moving slowly, this detector is a joy to use as it's— really in its element. So, for the water, I recommend leaving it in stock form; and if swimming, utilize the supplied shorter lower stem piece.
The new headphones, another major change, feature a lower, more pleasing tone. These headphones will still come off in the surf, however. The cure is a stocking cap or dive hood over the whole thing; then you can bounce around in the surf as much as you want. Ed Grella of Eastern Detector Sales in Fairfield, Connecticut suggested I pass along the following tips from a phone conversation we had: The Excalibur talks! By that I mean that the target signals generated in discriminate mode are unique and communicate in four different ways:
1. They vary in length of the sound caused by the target's size and shape. A long sound may indicate an aluminum can, while a coin signal will be short.
2. They vary in pitch (high or low) according to field density. I can hear about seven different pitches in the discriminate mode. Silver is at the high end; foil, thin aluminum pieces, etc. are at the low end. Iron is silent. Gold can be anywhere, depending on alloy content, (10-14-18K) and size. Most small gold rings give a low pitch, at or below that of a nickel.
3. They vary in tonal quality according to the strength and length of the targets magnetic field. By this I mean that the signal could be a buzzzzz or a beeeeep at the same pitch.
4. The signals vary in volume (loud or faint) according to target size and depth.
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Finally, the discriminate mode signal can be a very distinctive combination of the above. Not many detectors “talk” in all-metal mode. The Excalibur does, using a single pitch. Nails are very distinctive. For example, a sweep of a lengthwise nail produces two beeps. A nail beep may sound fuzzy when starting &/or ending. Generally, all iron signals are slightly fuzzy at the beginning and end. A nail may start low and end up louder (beeEEP), or the other way around. It may have a r-r-i-IP type of sound. Very few non-iron targets r-r-ii- p. Still, always check a target in discriminate mode. One in 20 times you may be surprised with a good signal. Coins on edge will occasionally doublebeep.
I wish I could have had a Minelab Excalibur while nuggetshooting in Western Australia in 1984. You might think that the Excalibur is inappropriate for finding gold nuggets; however, you would be amazed at the tiny, BB-size targets I've chased around (with both the new 8" and 10" coils) because they were too small or the scoop. Also, the Excalibur handles heavy mineralization interference better than any other VLF detector. I've said for years that the BBS technology is capable of finding bigger nuggets deeper than current single-frequency machines. There have been many Minelab Sovereign BBS detector gold nugget finds in Australia, and some here in the States, too. (The Sovereign is a non-waterproof version of the Excalibur.)
I use the following set of rules to determine whether to dig a target when using the Minelab Excalibur on the beach or in the water:
After detecting a target in all-metal mode, switch to discriminate.
1. Obviously, if you get a good, loud signal in “discriminate,” dig.
2. In discriminate mode, if you get no change or reaction, but a steady threshold signal (following a faint signal in all-metal mode), dig a few inches and then try again. Actually, this is a sign that the target is a good one. Dig until you get close enough to get a reaction in discriminate.
3. Still, if the above allmetal signal is short, sharp, and positive, but the target still causes silence in discriminate mode, I dig it. Small gold rings will discriminate out if they are deep in a moderately mineralized environment.
4. If the target discriminates or nulls out (silent threshold), but the returning signal comes back lower in pitch, dig. A lower-pitched signal after a null will occur more often than a higher one. I dig the higher ones also. Again, this situation is caused by a uniquely mineralized environment, common in the Los Angeles to San Diego area.
5. If the signal in either mode is scratchy, crackles, or is just generally weird, I think “gold chain” and dig carefully. Usually it will turn out to be a small piece of foil or aluminum from a can. Bottle caps vary immensely in content, and the signal from one can crackle or be solid.
Ed, who lives on Long Island Sound, says that although the waves there seldom exceed 2', targets get exposed and buried regularly by sand movement in the Sound, just like anywhere else. There are plenty of tides and currents that move the sand around, transporting and covering targets. In that environment, for the deeper targets, he likes to hunt in discriminate mode.
These conditions are just the opposite from the situation in the San Diego area. In a heavy nail zone at La Jolla, for example, I sometimes hunt in discriminate mode. The Excalibur truly offers a wide range of detecting options to cover all the different in-ground environments. The depth of the discriminate mode, as compared with all-metal mode, varies from beach to beach. At La Jolla Shores, there is not much difference; yet 20 miles south at Imperial Beach, all-metal goes much deeper. Remember, it takes a particular frequency to penetrate a particular environment. That's why Minelab's 17-frequency BBS technology excels!
The Excalibur's narrow double-D coil is very good at separating good targets out of an iron-contaminated area. With a fore-to-aft, 1" wide detecting field that extends straight from the front of the coil to the back, it's like a vertical butcher knife blade. In my opinion, a conventional inverted cone-shaped concentric-would coil's field cannot separate close targets as well. Also, the double-D field's rectangular shape (looking from the side) covers more than twice as much ground volume than the concentric coil's cone-shaped field with each side-to-side swing. Minelab's double-D coils are more expensive to manufacture and also incorporate a built-in transmitter.
The bottom line is, you get what you pay for!
DON BARTHEL is the author of The Beach Hunter's Guide, from Beginner to Pro. Detecting since 1972, he says “Now with the computer age and the lightning-fast advancement of detector technology, it's even more enjoyable!
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