Chet

Some years ago a friend brought his GPX 4500 to me to see if I could fix it. He had taken a hard fall on a large rock pile when it quit working. It had been through multiple owners and long past its warranty period. Attached is a photo of a broken ribbon cable that resulted from his fall. Evidently a rock impacted the battery cable and connector flexing the aluminum faceplate far enough to tear the thin plastic ribbon cable. At the time it occurred to me that that the short span between the 5 pin battery connector and the adjacent toggle switch did not have enough flex loop. The ribbon cable may have been weakened by many years of repeated flexing from connecting and disconnecting the battery cable and sideways straining of the cable in normal use. In our detecting areas the cable gets tangled in a lot of brush and suffers many stretch events. With a lot of patience I bypassed the five broken circuit paths with thin flexible jumpers. In Jennifer’s photos the blobs of solder may have come from replacing this ribbon cable?

My choices for Elliptical coil sizes are; 9” x 6”, 14” x 9”, and 24” x 15”. For Very Low Frequency (VLF) detectors with high length to width ratio elliptical coils such as Big Foot coils work well for coin and relic hunting. In my opinion Pulse Induction (PI) gold detector elliptical coils should have more conservative ratios of less than 1.60 : 1. I think conservative ratios provide a good balance between detecting small shallow nuggets and larger deeper nuggets. If the goal is to detect mostly very small shallow nuggets then higher elliptical ratios of 2:1 or 3:1 in small coil sizes may be desired. Have a good day, Chet

Tony When detecting in trashy areas, gullies and desert washes I frequently carry a VLF along with the GPX 5000, GPZ 7000 and now with the GPX 6000. If roaming large areas of desert with only an occasional bullet or boot tack to contend with the VLF is left in the Jeep. Over many years as VLF detectors improved the models for this purpose were upgraded from the early Goldmaster series to MXT to GMT to Gold Monster to now to a Equinox 800. All equipped with the smallest coil available. When a target is detected in a trashy area with the Large PI coil it is quickly pinpointed and discriminated with the VLF. If is too deep to detect with the VLF it gets you pumped up a little thinking that this is something good. As the hole gets bigger and deeper the small coil on the VLF pinpoints the direction to dig. Sometimes a dozen plastic knives with bright colored surveyors ribbons tied around them are used as markers. Detect the area with the PI. If a shallow loud target is detected lay a knife over it. If it is a weak low broader signal place the blade into an upright position. Lay the PI down and detect each marked target with the VLF. The shallow loud ones are fast and easy. The deeper ones require some aggressive digging to get the VLF close enough to detect, pinpoint and discriminate. From years of experience with many detectors has led to this determination. The Equinox 800 with the small coil is the best, simplest automatic detector for this work and/or for stand-a-lone gold detecting. It has a build in pinpoint mode that immediately gets you on top of the target. Once on top you punch it back to discriminate mode and one or two sweeps you know whether it is ferrous, nonferrous or a hot rock. The target number read-out is so much better than the Gold Monster bar graph. Like most modern highly sensitive VLFs built for gold detecting it will sound off on many hot rocks. But it will have a repeatable number read-out that will correlate to the normal hot rocks produced in that area. Have a good day, Chet

I spent 6 weeks camping in Canada and Alaska in the summer of 1989. It was a great road trip except for the mosquitoes and flat tires. I did master the Canadian salute; the action of slapping them flat on my forehead.

All detectors are of little use at 1m depth unless it is that rare multi-ounce retirement nugget. As previously stated you must remove the overburden. Watch Rob’s video on this forum at; https://www.detectorprospector.com/forums/topic/16593-part-2-dig-shovel-rake-metal-detecting-for-gold-nuggets-video/#comments Have a good day, Chet

The camera operators and TV directors are probably wearing them lol.

The detecting environment has some effect on the choice of coil cable routing and placement. It was like sliced bread was reinvented when the GPZ 7000 came out with the taut tight-fitting stretched cable inside the detector shaft. Gone were the days of messing with rewrapping loose floppy cables with Velcro with each coil change. Experience with the GPX 6000 in bushy areas has re-induced an external cable problem. Leaving a loose loop above the coil causes frequent false target sounds when swinging into or pushing under bushes. Normally setting and raising the detector is a small percentage of the time spent in detecting. Sounds generated during those motions can be accepted. Have a good day, Chet

Thinking of the present situation and a possible solution; In the world of corporate profits Minelab probably does not gain much on the selling of additional coils for any detector that they sell. In past years they probably have profited more through more sales of detectors by allowing other competing coil manufactures to produce a wide array of available coils at competitive prices. Two Minelab software changes would allow existing coil manufacturers to very quickly provide a wide variety of coils for the GPX 6000. Those changes are to remove the Coil ID and Security check; Replace it with a check to test for a signal/noise present or not present on the Double D receive coil. If a signal/noise is present then a Double D coil is connected. If no signal/noise is detected then a Mono coil is connected. Removing the ID and Security chip simplifies and reduces manufacturing technical processes and costs. This will provide both a better profit margin for the manufacturer and a reduced cost to the customer. In the long run allowing an open competitive coil market will sell more expensive detectors as it has with the previous GPX series machines. Have a good day, Chet

It is hard to understand why Minelab has again closed the door with proprietary connectors and security chip methods to prevent aftermarket coils if they don’t intend to provide other coil choices to their customers. The X-Coil method may again be the only option for other coil options for the GPX 6000. Minelab has certainly made it more difficult to make an adapter but if it is accomplished it will open up several coil choices. The GPX 6000 11” Mono coil has the same electrical specifications as most previous GPX series coils. That is; the inductance is close to 300 microhenrys (uH) and the resistance is close to 0.3 ohms. And shielding appears to be similar. If the X-Coil adapter method is wired to a standard 5 pin GPX connector configuration it should allow other X-Coils that are already built for GPX series detectors to be used or adapted to the GPX 6000. Existing Minelab GPX series Mono coils and other aftermarket GPX series Mono coils, depending on the quality and shielding effectiveness, may also perform well with the X-Coil adapter method. A workable and performance quality list could be established by a few users that still have GPX series Mono coils. The GPX 6000 Double D receiver coil is different from previous GPX series Double D coils. It appears to have a capacitor in series with the winding and appears to have more turns in the winding. Using existing aftermarket Double D coils on the GPX 6000 would probably not perform well. X-Coil would most likely be the only supplier of GPX 6000 Double D coil options for such a small niche market. Have a good day, Chet

Steve I edited some notes into the x-rays that may clarify this somewhat. Have a good day, Chet

I grew up in a logging family on the Oregon coast. We had plenty of complaints about the US Forest Service and their rules and controls. Some of my old complains have carried over about road closures into areas that have gold. I decided to goggle some facts on the USFS. They are responsible for 154 national forests and 20 national grasslands containing 193 million acres They are responsible for more than 380,000 miles of roads in our national forests and grasslands—that’s eight times more than the U.S. interstate highway system. The Forest Service has a workforce of approximately 30,000 employees. Even with seasonal workers and firefighters the numbers are remarkable. I now have a better understanding of their problems. Have a good day, Chet

After soaking overnight in CLR my 6.2 grams dropped to 5.98g. I didn’t test the GPZ 7000 on any of the GPX 6000 undug nuggets. I did fire up the 7000 and hunt for less than an hour as I used the built in GPS to home in on two Find Points from five years ago. As many of us do, I slowly circled and crisscrossed tens of yards all around those dig holes at that time with the GPZ-14 coil. I marked the old filled-in dig holes with dead sage brush and took the 7000 back to the Jeep. I didn’t want to drag around that heavy 7000 when I was enjoying using the 6000! I returned with the 6000; found two small nuggets each nugget was within three feet of an old dig hole. Then I found the 2.6g nugget less than a hundred feet from either of the old dig holes. This was in ground that I and others had been over several times over the years. Have a good day, Chet

When will GPX 6000 17” Mono Coils be available? Will Minelab produce any other coils for the GPX 6000? Smaller Mono and Double D elliptical coils would be useful in gullies and brush. Minelab may again do a disservice to both their dealers and customers by preventing other coil builders from providing competitively priced custom coils for the GPX 6000. While at the same time they may again not provide additional Minelab coils that are desired by customers. Short time materials shortages or small ID-chip shortages may not be a valid excuse for not having relativity small numbers of coils to be manufactured by Minelab subcontractors. Minelab should provide the dealers and customers a reasonable path ahead for additional coils. If they don’t have a clear and timely path within the company then they should open the door for competitive coil manufactures to produce them. The fastest and most cost effective way to do this would be for Minelab to patch the software to not test for an ID chip within the coil. Instead only test for an existing Double D receive coil winding. If the Double D receive winding is not detected then it is a Mono coil. This software patch would allow coil manufactures to go into production quickly without additional wiring, ID-chip programming and testing and associated electronic equipment. This would also reduce production cost and reduce final cost to dealers and customers.

Norvic in HAM talk; we may need to work out detecting days or hours between countries to avoid generating EMI between us via the Ionosphere Skip during the Solar Max period LOL. This could explain the frequent need to retune our detectors as the Ionosphere is changing between us lol.

Maybe this is where some of the GPX 6000 chips are made. https://news.yahoo.com/trucks-fresh-water-used-feed-130941849.html