Chet

I have Red stapler and am keeping it until you show me to the patch 😄 Happy New Year! Chet

The shape and angle of the target distorts the magnetic field which causes inaccurate pinpointing of the target. If the object is a spherical shape such as a BB or if a nail is in a vertical position then pinpointing will be fairly accurate. Hot rocks and mineralization may also cause some distortion. Soft iron has the most effect since it combines/concentrates and intensifies the magnetic lines of force. Gerry’s techniques above are about the best you can do to save on digging so many big holes. The attached drawing is an approximation of how the transmit and receive magnetic fields are distorted.

If it was so easy with a metal detector then many in the Philippines would not be mining in deep mudholes such as in the following. https://www.youtube.com/watch?v=8psB-o-er5k

Looks like good country to look in and just being there is great. Recommend reading this post if you haven’t already. My Tips On Nugget Detecting With The Minelab Equinox https://www.detectorprospector.com/forums/topic/7468-my-tips-on-nugget-detecting-with-the-minelab-equinox/ Have a good day, Chet

Mitchel Running over the detector and breaking the lower shaft says a lot about how well the Russian coil is built. It was supporting a huge weight from a loaded vehicle. Have a good day, Chet

This is an excerpt from one of my previous posts; It is reasonable to be concerned about interference from the two connectors being located so close to the coil. This is not a problem since the detector only detects motion change relative to the coil. A simple experiment will demonstrate how the detector nulls out metal that is not changing position relative to the coil. Place a small test target (0.06g) on the ground with an aluminum soda or beer can about 2 feet from it. Swing the detector over the small test target. You will only hear the response from the large can. Now tape the can on top of the detector shaft 2 feet from the center of the coil. Now swing the coil over the test target and it will be detected. With the can attached the detector it will sound off as you lift and lower the detector to the ground since the coil is remaining flat while the shaft and can are changing position relative to the coil. In normal detecting when setting the detector down or lifting it I hear this sound-off with the 17” x 12” coil but not with the 10” or the 17” round coils. There is no effect during normal detecting since the coil is not tilting or changing position relative to the shaft. Have a good day, Chet

Using other materials that Jason mentioned can be used on small coils where the coil is wound around a small core. Small AM radio antennas use a ferrite core to great advantage. Some pin pointers and metal detector probes use ferrite rods to reduce the size and concentrate the magnetic field. But the cores weigh more than the wire wrapped around them. Any material used must not dampen the high frequency positive and negative transitions of the ZVT waveform. Which is much higher than any VLF frequency. I haven’t seen an example of using a light weight dispersed or a ring of material in a method that would work to an advantage in our use. Just for information in the photo of the inside of the Minelab 14” coil. The entire coil assembly is encased in rigid foam and then suspended by soft rubber mounts through the four large holes in the center. As for purchasing a new coil; I have a wait and see what our Australian friends report. It needs to have improved performance over the Minelab and similar sized Russian coils at affordable price to be a good seller.

In the ZVT function there is an abrupt square wave transition between reversing high positive and high negative current levels. The transition periods are a high frequency function that requires Litz wire for efficiency. The Minelab and Russian GPZ coils both use Litz wire in the Transmit and Receive windings to reduce high frequency energy loss. Magnetic eddy currents from nearby wires have opposite polarity and cause energy loss in coil windings. There is less energy loss in single layer Spiral Litz windings since there are no adjacent wires above and below the single layer. Some energy loss still occurs in single layer Spiral windings. That loss could be reduced considerably by a spacing of five wire diameters between each winding but there is not enough room in the coil housing to allow this much separation.

Here are some thoughts and trade-offs that companies may consider on how to reduce the weight of a coil. Use smaller gauge or less copper wire. Bunch wound coils use a little less wire than Spiral wound coils which can reduce performance. Smaller gauge wire in the transmit winding could reduce overall performance. Use less plastic by reducing the overall thickness and strength of the housing and the shaft attachment area. Use lighter weight foam or other material to fill and support the windings within the housing. Some lighter weight fillers break down with age and heat. Consider method to prevent false signals when bumping into rocks and brush. The internal coil and foam mass in the Minelab 13” x 14” coil is suspended in the center under the shaft mount by cushions. It does not touch the surrounding housing. Other standard methods use glue/epoxy to rigidly tie the coils down to prevent any movement. The amount of heavy material vs. foam used can add considerable weight. Provide the coil without an optional skid plate will reduce the weight of a 13” coil by about 120 grams or 4.3 ounces. The final trade-offs must result in a coil that will satisfy the customer.

Having the D-ring positioned higher on top of the shoulder puts more of the load onto the back of the shoulder or even a lifting effect on the back strap instead of having a downward load similar to a backpack load.

I have two favorite picks. One is a 3 pounder and the other a five pounder. Either one is carried on a padded military belt. The pick holder is a Drill Pouch from Home Depot. It is attached to the belt with a 10/32 screw, fender washers and locknut. It swivels and allows the pick handle to be slid into the large opening without looking. The five pounder is often carried in my left hand when hunting without the Equinox in areas with little trash. Both picks have rare earth magnets attached so they can pick up much of the trash. The key to carrying heavy picks and heavy water loads is the padded belt. Wear it tight so that the load is on the hips. The shoulder straps are loose and only needed for the Hip Stick and Bungee cord attached on top of the shoulder. Having the top of the Hip Stick at top of shoulder height prevents pulling down on the shoulder. https://www.ebay.com/itm/NcStar-CVBAB2939T-TAN-Military-MOLLE-Padded-Contoured-Battle-Belt-w-Pistol-Belt/202863959802 https://www.ebay.com/itm/Condor-215-Tactical-MOLLE-PALS-H-Harness-Suspenders-for-241-Gen-II-Battle-Belt/233531915902?var=533171366300 https://www.homedepot.com/p/Husky-1-Pocket-Drill-Holster-GP-45854N13/204853194

Many years ago a local Mining Supply shop had a break-in with a much better outcome. The shop was full of expensive dredges and metal detectors. The glass counter had gold and antique guns on display. The owner had an alarm service that informed the police of the break-in. They responded too late to catch the thieves. They ask the owner for an estimate of what was missing and a value for their report. He looked around and to his amazement the only thing missing was a large galvanized tub full of sand and water salted with gold for customers to learn how to pan for gold. They followed a trail of spilled water down the street to a room in a cheap hotel and arrested two drunks panning for gold. Have a good day, Chet

Yes I tried that. My mistake was not transferring the Find Points to the Exchange2 program before loading the software fix into the GPZ 7000. The GPZ 7000 manual states that the GPS limits are 100 Find Points, 100 Way Points and 10 GEO Hunts. So I will store the Find Points in the Exchange2 program in three files; California, Nevada and Arizona. Then load the detector with the appropriate state Find Points prior to leaving home. Have a good day, Chet

The other settings are mostly the default settings except the Threshold is set at 1. This area was well hunted with a GPZ 7000 and a Gold Monster. So seven of these nuggets were barely detected with the 7000. I tried different settings on the threshold on some of them. It just caused a lot of noise and the small nuggets were more difficult to hear with the noise.

I always run with the GPZ 7000 in enhanced GPS mode and record all Find Points. When Minelab fixed the GPS software I accidentally lost approximately 50 find points when I loaded the fix. On this trip when I tried to record the fifth nugget location it would not accept the Find Point because it had limited out at 100 Find Points. In the trashy areas I hunt with the Equinox 800 with the small coil in my left hand and the GPZ 7000 in my right hand. That way I can discriminate out most of the shallow trash. The 10 nuggets were all to deep for the Equinox to detect until some of the material was removed. Then it becomes a pin pointer so the holes do not need to be so big for the GPZ 7000 coil.

Brian we really do need to put big numbers on those big round rocks and big trees. LOL Chet

In one of the many hydraulic worked areas.

The area was decimated by the California miners in the 1800’s. It has since grown back scattered pine trees which are now dead from disease or fire. Little shade so the temperatures were close to 100F or 37C.

Steve, what a great history with so many great gold nuggets found. Thank you for your story. I sat glued to the screen for the length of the video. My wife was also very understanding of my trips; hunting, fishing and gold prospecting. My son and I made 6 week camping trip through Canada and Alaska during the summer of 1989. We spent a week camped behind the Chicken, Alaska Outpost. I got some good gold panning in Jack Wade creek. We were there when George Robinson met his maker. He had many claims on Jack Wade creek. Have a good day, Chet

Finally got out again with the 15" x 10” X-Coil. It ran really quiet and smooth continually in High Yield, Normal, at Sensitivity at 20. Found 10 small nuggets for a total weight of 4.55 grams. They were between 5 to 8 inches deep in a California pine tree area. The X-Coils work great, but the 15 x 10” is now the go to coil. Have a good day, Chet

At to days gold price alone the nugget would be worth close to $3,000,000. Of course a lot more at auction. Just think there are more of them out there just waiting for some lucky person. From the Aussie Gold Hunters video; the dig holes are probably similar to the ones described in the story above. Just think of digging straight down to a clay area or bedrock then tunneling horizontally without shoring up the walls or roof. I would prefer to be the guy lifting the bucket and disposing the dirt.

Maybe a hand held detector for Archaeology and/or Geocaches?

This is a long read but a fantastic story! https://www.mindat.org/article.php/516/Australia's+134+Pound+Gold+Nugget

I do wear gloves all the time while detecting. They protect fingers as trash is slid sideways off of the powerful magnet. Some small black sand and tiny particles remain with no problem except appearance.

Two part epoxy ‘J-B Weld’ works great to attach and coat rare earth magnets to picks, rakes and other tools. After a lot of use the J-B coating will wear thin but it can be built up with a fresh layer. Have a good day, Chet