HardPack

Yeah, in our dreams! Coiltek offers the only after market coils for the Minelab Equinox 900 correct? Neither Minelab nor Coiltek offer a concentric coil option. How many of us purchased the Coiltek 10x5 Nox for either the 800 or 900? Considering the SMF EMI issues would a 8 inch concentric coil reduce the impact? Not to mention a cleaner shallow target signal? What are you waiting for CoilTek? How much more pend up backlogged demand do you need?

My ears may prefer the 8 ” concentric. How does the Vista X stock 11x9.5 DD coil perform in ferrous trash?

I’ll give them look see. Thanks

Is there another IB option?

Standing by!

Took the ML EQX 900 back to EMI site today. The powerhouse and overhead high voltage towers could be seen four miles north across canyon from the site. Modern trash: brass shell casings & lead bullets. Set the ground balance to tracking (GB 40’s), volume 22 for all tests. Starting in search mode Park 1, noise canceled with Sensitivity 0, Tone 1, Recovery 0. Adjusted the Sensitivity until the EMI level became audible at Sensitivity 10. Adjusted Sensitivity to 16 then increased Recovery to 4. The EMI audibles were spaced, intermediate but workable in Park 1. Switched tones from 1 through 3, 5 & At with no observed change in EMI level. Stayed in At-All Tones for the remaining tests. Started detecting adjusting to Sensitivity 18 and Recovery 5 with noise cancels with each setting change. EMI audibles were closer together but still workable. Throughout the day cycled through search modes Park 2, Field 1 and Field 2 at Sensitivity 16/18 Recovery 4/5. EMI audibles were workable in all search modes above. At Sensitivity 20 & Recovery 4 or 5 EMI levels were at the edge but still workable; Sensitivity 22 and above EMI levels were not workable. Did not search for any length of time in Gold 1 & 2, EMI audibles were very close, loud, difficult to hear targets. EMI levels may have been lower when the coil was sweeping near the ground but the EMI audibles could still be heard. Target depths for non-ferrous ranged from near surface to 4 inches (brass & lead); 3-4 inches ferrous square nails; 6 inches for 3 square inch ferrous (cast iron), did not dig rusted cans. Soil depths varied from tight/shallow on the flats to loose/deep hillside soils. Bedrock: black slate. Coil: 10x5 Nox Coiltek. Headphones: none. Find of the day a 40 caliber lead ball. Thank you all for the suggestions.

Here is the Nexus V2 with a 7 kHz 10 inch DD; RGB LED Red- non ferrous, Blue- ferrous

I just discovered the Nexus while searching for a detector not as susceptible to EMI as the new digital SMF detectors but with some discrimination capacity and the ability to handle highly mineralized ground. In the manual under “care & maintenance” only the coils are waterproof. The V3 inland sites and fresh water beaches with a 9 inch coil at 7kHz or 24 kHZ may work best for my applications. Hopefully, members with either model will provide some further insight. Here is the link to RGB LED Target response video mentioned above:

Ain’t Christmas yet. Headed out tomorrow morning with my notes in hand. What’s fringe testing?

I just noticed a few coin & relic hunters detecting with the Nexus Metal Detector. The Nexus is an analog induction balance ((IB) VLF detector offered in two models V2 &V3. The interface is a RGB LED meter; Super Damping Technology (SDT) enables detecting in heavy mineralized ground conditions and strong magnetite. The V2 model is for inland sites and tidal salt water beaches; modes: All Metal & Discrimination; LED red- non ferrous and blue- ferrous. The V3 model is for inland sites and fresh water beaches; modes: All Metals or VCO multi tones; LED Green- low conductors, Orange- mid conductors, Purple/White- high conductors. There are a variety of different single frequency coils. See the website for manuals, coils, EMI, etc. www.nexusdetectors.com. This detector may not be for everyone but I find the controls similar to the White TDI pulse Induction which does not offer a discrimination feature. The youtuber “Beep n Dig Relic Hunting” has several Nexus videos including a closeup of the RGB LED with target responses.

Turn the contrast up on the coin, you may make on the date. Looks like ?87?. Post the story, we all know the artifacts were left in place. I was talking to a local archeologist over a turkey dinner about one the emigrant trails crossing the Sierras. Turns out they found an old powder horn with an engraved brass tip along the trail, late 1830 to early 1840’s. No records of whose oxen pulled over the summit but portions of the trail still exist. All the pre-gold rush natives, explorers, beaver trappers, path finders and early settlers passed this way from east to west and west to east. They didn’t name Carson City for Johnny. Post it Doc

Doc, See you’re out North California or Southern Oregon. If I recall correctly The Hudson Bay Company was trading into southern Oregon in the early 1800’s. They may not have reached as far as the Salmon or Klamath drainages but their trade goods may have. Even earlier the Russians were trading out of Fort Ross. The Jed Smith party passed through the area in the 1830’s. Sea ports in the area provided goods to the miners in the 1850’s. I can’t determine the length of the upper knife but the dagger shape and double cutting edges may point to an old rigging knife. The old timers would often use them as a boot knife for protection as needed. You may have yourself a real historic find.

Interesting finds. Can’t help but wonder about the history behind them. The pick has me thinking old pocket miner, the spring near an old cabin site, the locomotive a family man down to his last quarter surviving on goat cheese but still able to curve a wooden handle for his old knife. The wife must still be around if he’s shaving. When they parted ways he chucked all into the spring pond before heading back up the mountain. Great finds. You finding any smaller caliber lead balls?

“ The Equinox Series detectors are highly sensitive and have adjustable Sensitivity. Setting the correct Sensitivity level for individual detecting conditions will maximize detection depth. “ ML EQX 900 manual Page 18. So is Minelab saying the stronger the transmit signal the stronger the return signal. The higher the ground mineralization the higher return ground noise. If so then reduce Sensitivity level? “Note: While Auto Noise Cancel selects the ‘quietest’ channel based on several criteria, the selected channel may still have some audible noise. To try and reduce noise further, consider adjusting Sensitivity.” “ Auto Noise Cancel: #1 Hold the coil stationary and away from the ground.” ML EQX 900 manual Page 25. So what is being adjusted here with the Sensitivity settings. Does EMI affect detection depth. Should the coil be held away from the ground when adjusting the Sensitivity level? I do not engage in air tests, nor has it been a topic on this post. Thank for your reply.

On the ML EQX 900 no gain control only volume.

The EQX 900 manual on page 25 suggests adjusting the Sensitivity level if some audible noise remains after Auto Noise Cancel. So it appears Sensitivity is not just for ground noise. Also Manual Noise Cancel may help in areas with lots of electrical interference. I may be spending some time adjusting & balancing to see if there is method to fine tune the machine.

Want to get this out there: The sites I am attempting to detect with a SMF metal detector have several conditions in common: old gold mining camps; located within the Melones Fault Zone (California Mother Lode) and the eastern gold belt; are carpeted with ferrous trash; loads of non-ferrous trash; coins, tokens & gold are all in short supply requiring a lot of effort to uncover. Today the Melones fault plus the Feather and Yuba watersheds have become the home for water storage reservoirs, electrical generation stations and overhead high voltage transmission lines. These power station are not only located at the lower elevation dam sites but also near higher elevation reservoirs. Many of these power plants control rooms have converts from analog to digital. Microwave signals are often transmitted between a central control room to these remote power stations. Adding to this are the mountain top cell phone towers with G4 & G5 resulting in an abundance of Electro Magnetic Interference (EMI). In order to deal with these site conditions and especially the EMI, I wanted to have some rough Idea of what the Minelab Equinox was transmitting into the ground. I recalled an older forum post (“What’s the Difference” comparing the ML EQX 800 to Nokta Legend, Dec. 30, 2021). In that post PimentoUK provided the following information: “…The Equinox simultaneously transmits 7.8 kHz, 18.2 kHz and 39 kHz in Park1/2 , Field1/2 , Gold1/2 modes, this is an easily observable fact. My personal opinion is that: Park1 and Field1 place the emphasis on the 7.8 kHz, and use the other two freqs to help reduce ground signal. Park2 and Field2 place the emphasis on the 18.2 kHz, and use the other two freqs to help reduce ground signal. Gold1/2 place the emphasis on the 18.2 kHz and 39 kHz , using the 7.8 kHz to reduce ground signal. The difference between the two gold modes is something I could only speculate about…. There was follow up discussions on the “return signal analysis”. Prior to the VLF SMF detector the problem was using a VLF single frequency near iron rich ground. VLF detectors offer a discrimination feature Pulse Induction detectors do not. In the iron rich gold bearing regions EMI has added another problem especially for VLF SMF detectors. Other than switching the SMF detector to a single frequency, is there a real solution?

Okay, took some notes. For now changed Park & Field search modes from All Tones to five tones. A storm is moving in so it will be a few days before I can get back out to the site. Thanks

Thankfully I wasn’t using the wireless headphones. The nearest ranch houses are half mile to the south and 4 miles over a ridge to the south. There are no buried utilities or overhead power line passing near the site. Vehicle traffic is light so I assume the cell phone signals would be intermediate. The stream channel vertical slate banks served as an EMI echo chamber. Perhaps there is a new unknown cell tower nearby? On this specific site switching to a desired single frequency may be the only option. Ground balancing over the site ferrous trash presents its own unique problem of just finding a clean area to pump the coil. When a high tone is heard switching to “all metal” to check for ferrous then narrowing the coil sweep over the non-ferrous target works. I am thinking of switching to “ground tracking”, keep multi-frequency, switching to a single frequency and “all metals” as needed. If that fails a remote move inland may be in store for this SMF detector. Thanks for the insight

Recently detected a ferrous rich old mining site for coins & relics using the Minelab EQX 900 experimenting with Park 1 in multi-frequency with factory settings except All Tunes and Iron Bias 2. A road crew was working within a 1/4 of a mile. The detector was definitely picking up EMI from the flagmen radio traffic. There is also an electrical power plant 4 miles line of sight to the north, an overhead high voltage electrical line 12 miles line of sight to the east and a mountaintop microwave station 14 miles line of sight to the northwest. Performed multiple frequency scans and adjusted the sensitivity down to 15 and below, neither reduced the EMI noise level. Five hours later the road crew departed but the EMI grew even stronger. (The power plant gearing up as folks return home from work?) The racket from the EMI was both tiring and annoying but I was able to separate out non-ferrous targets. I have detected this area for years with several single frequency & selectable frequency VLF detectors ranging from 15kHz to 54 KHz plus pulse induction detectors. I have never experienced this level of EMI in this area. I have been using Park 1 and Field 1 in an attempt to pull out deeper high conductors on heavy ferrous trash sites. Apparently that is a no go with SMF in either of these two search modes. The mining site is blanketed with ferrous trash, gold 1 & 2 would require a dig all approach without discrimination. It appears at this point the only option is Park 2 and Field 2 in either multi or single frequency. Has anyone else experienced this EMI problem with a SMF detector?

Fast forwarding to December, 2023: I am now detecting with the ML Equinox 900 with a 10x5 Coiltek. I am attempting to find which search mode(s)/settings fit the particular site conditions. The sites have several conditions in common: old gold mining camps; located within the Melones fault zone or up canyon; are carpeted with ferrous trash; loads of non-ferrous trash; coins, tokens & gold are all in short supply. Today the main fault and river canyons have become the home for water storage reservoirs, powerhouses and overhead high voltage transmission lines. EMI is a real problem for SMF detecting in this area. In order to deal with the site conditions I wanted to have some rough concept of what the EQX 900 was transmitting into the ground. I probably should care more about the return signal analysis than I actually do but in actuality I only do the shovel work. During my forum search I rediscovered these posts from December 2021 regarding the Minelab Equinox Multi IQ search mode “frequency weighting of the multi-frequency signals”. At the time of the original post I was not aware of the problem SMF detectors have with EMI. The EMI levels are tolerable for non-ferrous targets such as coin, brass shell casing, lead bullets casings. In Gold 1 or 2 I have my doubts. After detecting in Park 1 & Field 1 the EMI remained a problem even after multiple frequency scans and adjusting the sensitivity down to 15 & below. During further research on the forum I also read: - lower frequencies penetrate the ground deeper producing better responses on high conductors. - low frequencies unmask high conductors from non-ferrous trash, notably better than either mid frequencies and/or high frequencies. - Park 1 is more susceptible to EMI, which I assume would be the same for Field 1. I am impressed how well the detector can herd out a non-ferrous target amongst the ferrous trash. It is just a matter of time before something goods turns up. At this point I have no specific question but thought the information from the original post could be of some help.

This good to know information. I have a site loaded with non-ferrous trash then mixed and covered by a blanket of ferrous trash ranging from small rusted can pieces, nails, you name it I have detected older silver in the past with an AT Pro (15khz). Detected the site a couple days ago with the EQX 900 in field 1, recovery 7. I played with recovery speed starting at 0 then adjusting up to 8 just to cut through the shallow ferrous. I pulled everything out the dirt except for the original owners but no silver. Field 1 is weighted on the lower frequency side but how low or at what range who knows. I know there are still good targets in the mix. Perhaps next time I’ ll go through the lower single frequencies in park 1 at a recovery below 5. Thanks for sharing.

I have read what remains of the Sierra Nevada Mountains is what exceeded the rate of erosion over the geologic time period of their existence. Prior to the uplift of the mountains there were approximately 20 miles of sedimentary and metamorphic deposits capping the granite batholiths that would form the base of the future mountain range. 55 million years ago meandering down an uplifting western drainage slope flowed several ancient rivers draining a plateau to the east that reached into central and eastern Nevada, These ancient rivers flowed through broad river valleys as they crossed the ancient plateau cutting through multiple gold bearing fault zones. As these rivers flowed down the western slope their currents curved through yet more gold bearing fault zones along the lower western edge of the drainage slope. Sediments and gold bearing gravels carried by these rivers were deposited along the banks of the ancient rivers and eventually as fans along the western edge of the drainage slope. In time the ancient plateau would extend into the basin and range complex. The western drainage slope would continue to uplift forming the Sierra Nevada mountain range. More recent rivers would head at the Sierra summits cutting different channels often through the ancient river channels robbing their beds of its ancient gold deposits. During the multiple ice ages glaciers continued to grind the mountains down to their granite core. Melt water from the glaciers would saturate the western sediment basin that filled the Central Valley. Yet today the mountain summits far exceed 10,000 feet and continue to climb. The river sediments that are not carried to the ocean continue to fill the basin to the west as deep as the mountains are tall. Although another range of mountains carrying sediments to the east Myron Cook, a geologist, demonstrates the scale of erosion that has occurred through the ages.

Steve, Here’s a short video by Myron Cook related to ice sheets & glaciers

Took the ML Equinox 900 to an old house site loaded with a variety of iron trash. The town site dates back to the 1850’s serving as ferry crossing to a stamp mill and gold mining sites (quartz & placer) across the river. However, I do not believe the house site dates beyond the 1920’s. The house was abandoned and demolished in the mid 1960’s. The original trail into the area passes by the house site. The site has round nails, tacks, small rusted can pieces, rusted flat metal sheet and old car parts plus nearby there is an overhead electrical transmission line. I am new to the EQX 900 and SMF. I typically detect by ear. This site is representative of old mining sites iron trash loads which makes for a good training area. I was attempting to get the ears tuned to the detector so I dug every target. Within the house site I stayed with “Field 1” at the factory settings except with Accept/Reject -19 to 0; 1 to 99, Recovery 0, Iron Bias 0, Target Tone 5. (Eventually changing to Recovery 7; Iron Bias 4, Target tones (At) All Tones.) Volume Adjust 22, Sensitivity 24. Coil 10x5 Coiltek. Ground balance 28. Upon detecting the house site with the EMI bubbling in the background (All Metals -off) the detector started falsing on the buried iron (ferrous) trash. The falsing tone signals were intermediate, with a wide spread of jumpy TID’s from mid to high positive, the falsing tones spiked quickly followed by a quick dropped off. Switching to All Metals would confirm the negative TID’s filling the spaces between intermediate iron falsing signals. Adjusting Recovery upward (as high as 7) allow the detector to “tone in” on non-ferrous targets within all the gun fire of both the EMI and iron falsing. Once a non-ferrous target was isolated the tone signal was fuller without the quick drop off and had a narrower TID spread. I did notice the surrounding iron falsing tone signals appeared to sound muted compared to the non-ferrous tone signals. Switching from five (5) tone to All Tones provided more tonal information. Once or twice I would raise and swing the coil over a non-ferrous target but did not hear a shift from multiple to single hits (shallow/deep target). Apparently gone with the EQX 900 is the overload booming sound when swinging over large sheets of buried rusted iron. I was not attempting to block or filter the iron falsing signals with Iron Bias and only adjusted the setting (no higher than 4) to see if I noticed any effect, which I did not. Outside the house site I switched to “Field 2” with factory setting except Accept/Reject -19 to 0; 1 to 99, Recovery 0, Iron Bias 0, Target Tones (At) All Tone. (Made no changes or adjustments). Volume Adjust 22, Sensitivity 24. Coil 10x5 Coiltek. Ground balance 28. Out of the iron trash and headed up the old trail I wondered amongst the cow pies detecting. After picking up my daily share the 22 brass and lead in both long and short rifle I dug up an old skillet. You know the older high sided lighter gauge skillets. I examined it long enough to ponder how much mercury and potatoes it had cooked off over the years before gifting it. Next I found an opened rusted steel beer can then headed cross country down towards the river where I detected the only coin of the day after several aluminum beer cans and pull tabs. Tones & TID’s were close enough on the non-ferrous target to dig and verify. Tones & TID’s on rusted cans were jumpy enough to identify iron with all metals. In the photo none of the targets are magnetic, all but the 1998 river quarter TID 87-88 were detected on the house iron trash site: the melted lead TID 50-51, button? TID jumpy 70’s, half sphere? TID 38-39, small tab? TID 10-11. Here a couple of questions for those more experienced EQX 900 users. In Target Tone: All Tones (Tone Volume: 4,25), have you noticed the surrounding ferrous falsing signals sounding muted compared to the non-ferrous tone signals? When lifting and swinging the coil to estimate target depth have you notice if the detector shifts from multiple (3) signals for shallower targets to a single signal for deeper targets?