Eqx 900 & Legend Separation

[HardPack]

I have not been able to determine the usefulness of the EQX 900 iron bias setting. It appears to only suppress the overall target signal. In the attached video the Nokta Legend has an iron filter, bottle cap reject plus an iron stability setting. It appears the Legend “iron stability” setting isolates and actually addresses false positive signals. What do you think?

 

[Digalicious]

The iron stability is "fine tuning" for the IF. 

IMO, the Legend's 10 levels of IF is more than enough. As such, I find the Iron Stability settings to be unnecessary. I leave my Iron Stability at mid level 3, and just use the main IF settings.

This may or not be related to that opinion, but Nokta removed the Iron Stability control in the Double Score.

[Digalicious]

I very recently explained the IF in this thread:

Nokta Double Score Or Legend? - Nokta / Makro Metal Detectors - DetectorProspector.com

 

[HardPack]

54 minutes ago, Digalicious said:

The iron stability is "fine tuning" for the IF. 

The XP Deus has the horseshoe, the Legend has ferrocheck and the EQX 900 has randomly spaced positive TIDs. Thanks for explaining the iron bias hi/lo settings. I have been using either 0 or 1 for the EQX 900 “iron bias” but the false positives continue to flood in with the 11”, 6” and 10x5 coils. Switching to All Metals only verifies the obvious ferrous target. Other than a shovel I have yet to find a method to identify a close adjacent non-ferrous target.

[Digalicious]

You're welcome.

I don't own a 900, but if you're getting a lot of true iron falsing with that low of an iron bias, I don't see what else you can do other than raise the iron bias, or dig it up to see what's going on.

When I'm hunting in iron with my Legend, I use 0 iron bias. When I encounter what I think is true iron falsing, I do the short wiggle over the target and watch Ferrocheck. If Ferrocheck shows little to no strength on the nonferrous side, and a lot of strength on the ferrous side, then I don't don't dig it.

[HardPack]

9 hours ago, Digalicious said:

If Ferrocheck shows little to no strength on the nonferrous side, and a lot of strength on the ferrous side, then I don't dig it.

I have buried multiple test targets from 6 to 8 inches. A coin on one side of the hole and a rusted square nail on the other (no overlap), all within a field of 8” deep rusted old iron (axe head, spike, horseshoe & flat plates with no rust halo effect). Tested each of the EQX 900 search modes in SMF, switching sensitivity up from 12, stepped recovery from 1 to 8 in each search mode (except beach), changed the iron bias from 0 to 9 in each recovery setting, used the same procedure with all three coils (11”, 6”, 10x5). The iron falsing drops off with the EQX 900 “iron bias” at the max settings but is not eliminated. With all coils Recovery 4, Iron Bias 1 at GB 40 seems to work best for depth and separation on test targets. With the 11” coil a clad quarter TID adjacent to a square nails is pulled down to 52. Outside the iron test area, except for nickels, the two smaller coils are unable to detect 6 inch deep coins in a granitic clay soil; none of the Nox coils have detected the 6” deep memorial penny. (side note: within the iron test area & out, the XP Deus with 9” X35 at 12kHz detected all ferrous & non-ferrous test targets at depth).

Actual site condition (typical placer mining site) is a blanket of rusted tin and iron with the same iron falsing issues at a similar ground balance but slate soils. With the EQX 900 picking up site non-ferrous targets away from the rusted tin/iron, nothing yet within the iron.

At this point with the EQX 900, if I have to starting layering down through the site iron trash I may be better off with a square nose shovel & screen.

Perhaps it is time to try a different metal detector.

[Tometusns]

15 hours ago, Digalicious said:

You're welcome.

I don't own a 900, but if you're getting a lot of true iron falsing with that low of an iron bias, I don't see what else you can do either than raise the iron bias, or dig it up to see what's going on.

When I'm hunting in iron with my Legend, I use 0 iron bias. When I encounter what I think is true iron falsing, I do the short wiggle over the target and watch Ferrocheck. If Ferrocheck shows little to no strength on the nonferrous side, and a lot of strength on the ferrous side, then I don't don't dig it.

That plus the sound is how I determine to dig or not except on a deeper target that has passed the ferro check capabilities. At that point it's the sound only that I rely on.

 I hunt with a very low recovery speed and the factory default IF setting. I know those air tests make it look bad but I've had very good results(bullets, buttons and coins) in heavy iron. I may be leaving targets but I'm certainly finding them as well and I'm not dumping out a pouch littered with nails/iron at the end of my hunt. I'm too old for that!  😁👍

[HardPack]

23 minutes ago, Tometusns said:

That plus the sound is how I determine to dig or not except on a deeper target that has passed the ferro check capabilities.

 I use the falsing signals also but unfortunately there is not a secondary iron check on the MInelab EQX 900, unlike the ML Manticore. With iron falsing there has to be some amount of masking of non ferrous targets. I am going to stay with the 11” Nox in Field 2 for now, it handles the EMI plus more target depth. However, both gold search modes hammered all the coin targets. 

[Chase Goldman]

16 hours ago, Digalicious said:

I don't own a 900, but if you're getting a lot of true iron falsing with that low of an iron bias, I don't see what else you can do other than raise the iron bias, or dig it up to see what's going on.

Bingo.

15 hours ago, HardPack said:

The iron falsing drops off with the EQX 900 “iron bias” at the max settings but is not eliminated. With all coils Recovery 4, Iron Bias 1 at GB 40 seems to work best for depth and separation on test targets. With the 11” coil a clad quarter TID adjacent to a square nails is pulled down to 52. Outside the iron test area, except for nickels, the two smaller coils are unable to detect 6 inch deep coins in a granitic clay soil; none of the Nox coils have detected the 6” deep memorial penny. (side note: within the iron test area & out, the XP Deus with 9” X35 at 12kHz detected all ferrous & non-ferrous test targets at depth).

FWIW - With the 900, I would personally up recovery speed from 4 and set the iron bias to max and back off on sensitivity to 20 or less to minimize falsing as much as possible in thick iron and see if you could cherry pick at least some shallow non-ferrous out of the iron muck recognizing you are just going to lose depth on deep non-ferrous regardless.  I mean in thick iron, depth is pretty much out the window due to falsing, masking, and target ID down averaging, so one of the first things I do in a thick iron patch after upping recovery speed is lowering sensitivity, the filters never really do much.  I know your test garden is showing you some potentially “optimal” settings but your test garden can’t really replicate all the myriad of real world 3-Dimensional ferrous to non-ferrous target spatial orientations, soil moisture conditions, and old target halo effects that can result in masking and falsing at your tough mining site.

The Deus might be a better tool in the thick stuff as well. I would tweak Silencer up or use Goldfield with mild IAR unless the soil is very mineralized (in which case I would set IAR to 0) and again lower sensitivity to focus on unmasking shallow non-ferrous.

None of the iron filter features on the peer detectors mentioned (Manticore, Legend) or Deus II are really going to work any miracles in your situation over and above your Deus and Nox 900.

If neither detector is pulling non- ferrous out of the iron patches with these tweaks, it might be time to start the tedious process of scraping and removing iron.

Good luck in any event.

 

[HardPack]

1 hour ago, Chase Goldman said:

The Deus might be a better tool in the thick stuff as well. I would tweak Silencer up or use Goldfield with mild IAR unless the soil is very mineralized (in which case I would set IAR to 0) and again lower sensitivity to focus on unmasking shallow non-ferrous

I plan to take the Deus out to the site after the storms move out. I set up a "Deep Relic" IAR program with the X35 for a starter. I'll take a small rake along too.