nordic

I think it was there from the start, but I only learned about it when put the detector on the metal sheet by accident. On the scope, the input signal from RX coil appears way above the unit supply voltage, so, in theory it may not be able to process it.

And the triangle usually means you are too close to large metal object, so big and so close it clips the signal going to the headunit.

Just their choice I guess, could be many reasons. For example, while web browser is allowed through local firewall, update app could be blocked and stuff like that, which would make user experience poor. Or firmware encapsulation is better through single executable. It also allows to switch the firmware in the field without Internet connection. There is probably pros and cons with either way...

I think ML updates are embedded into the update utility, therefore you would need to discard old and download the latest one from the website. I did mine today, went fine. Not sure if I need to reset the unit before and after though as with previous versions, but I did anyway.

Take away from this is that when this happens, you know it is shallow, shallow enough that even external pinpointer can detect it. And no need to dig deep and wide 🙂

Perhaps worth trying to reset and reflash the unit? Also, phones behave similarly when battery ages...

Thanks for the reply, this is interesting. There was a video a guy set it to -9 and the problem with stack of coins went away, was giving clean high TID.

Hi there, Thought to ask, perhaps it is obvious, but I don't know, are there conditions when GB can be negative, or why ML allow it to go negative? As you know it can be in range -9 to 99. I've never seen it going below 0. Many thanks!

Steady 1-2 is usually a coke or energy gels(some), Nox picks these up strong, but it can be moved to Ferrous side of scale. Field modes already do that. I've never found anything of interest below id 5...

Unfortunately cast iron can come as solid 13, and some other good objects can fall into 13 as well. When I see 13, I usually spend more time analyzing it. Rotating, using All Metal, listening to tone breaks. One other thing I think helps is using 50 tones, because rotating around does give small clues. There is also a certain character to iron, it has some raspiness in tone, while non-ferrous objects give this "rounder" kinda sounding tone. I think one can only hear it using 50 tones. There are other tricks that people use, I'm sure they will be mentioned here shortly.

I’m sure there will be more advices coming soon. In regards to bump sensitivity, generally it is not considered a problem as Nox is a very sensitive device. There were some reports of broken cable that can cause this though. But if you move the cable by hand and it doesn’t happen, then it isn’t the problem. My personal experience, that the latest firmware has least of this, including better EMI rejection. In regards to EMI, if it gives constant TID, you may try to notch it out. For example, some electric fences give me TID 30 every 5 seconds. I notch it out. There can also be radars in the area, that can give repetitive TIDs as well periodically. If it is repeatable, try notching it out. If TID is all over the place, then, perhaps, sensitivity or recovery speed must be lowered. Best regards

I just noticed, that conditions here where I live allow me to run Nox at full sensitivity, EMI never an issue outside, so I thought did ML exhaust sensitivity on this thing... Shortly speaking, yes, they did limit it to a sensible 25 to suit every user. It was just an experiment to satisfy curiosity. Sens 28 gives 6" coil another 2-3" in air discrimination depth, but air depth is hardly an indicator. Extra sensitivity rather suits special occasions, when grass is low, or perhaps beach hunting, low EMI, but I find I use it all the time... Anyway, this thread is about GB 🙂

As in topics Chase mentioned, ML pushed the Nox close to usability limits, as I found out later. I do think though, that they should've given users more sensitivity, because some, including me, like it running hot. It either reacts to the shaft (alu piece), cable itself or soil. During some experimentation I've assembled a simple device that gives me another ~3 sensitivity ticks (max ~28) and bump sensitivity is very apparent. While swinging gently, it is not an issue, but enough to bend the cable, tap the coil or put the MD on the ground, it bursts with TID numbers. Similar thing happens when GB is set high.

Wish ML just explained it better, or were more definite about it. In all time I spent with Nox I could not really tell if it makes difference depth wise or better target id. It does seem effect coil bump sensitivity, so perhaps with higher GB Nox is more sensitive? Noticed similar behaviour when artificially increasing sensitivity (25+)

As far as I could figure it out, you need to hit pinpoint button at a right time to lock the ID. Whether the PP mode then pinpoints according to TID, not sure. Sometimes it does, other times it pinpoints to whatever metal nearby.

Never heard of liquid tape! Good to know. I think the most important wire there, in terms of insulation, is the core of the shielded wire. It is the positive TX signal which is very powerful and probably will damage something if there is a contact. When Nox turns on it fires the TX signal at a reduced strength to check if all is good (not shorted, etc). After that, it is at full, even if the short occurres.

Have that too, faint hiss. Sound of switching power ouput.

I think it was mentioned somewhere, apologies for repeating if so, the water can get either through a ruptured speaker (salt water, etc) or battery compartment seal. Either way, it should be under warranty.

Thanks for the suggestion. I looked on the web for galena, it looks like it should be close to lead in softness? However it did take me a while to cut it, I'd say it is as hard as steel, or rather stainless steel as it does not seem to oxidize in normal conditions. Maybe chromium... Washed it few times, few burnt crust flakes came off, other than that it looks solid. Not sure what it is. Not a meteorite most likely, but interesting to know what it could be. It was found in the farming field that is far from anything industrial or even habitation. Not sure how to do a steak test, does the back of usual bathroom tile work?

Would it be correct to assume that multi-freq is outperforming any single freqs in most cases, except certain special need situations? Because that is what I witness normally - the depth and accuracy is far superior when using multi. Also, looking at the test box, it looks pretty small, wonder if there is a chance of magnetic field leaking through sides of the box too, as in, meeting no obstacles through air. On a side note, perhaps nothing new to some more experienced people here.. When looking at the RX signal scope, any magnetic, ferrous material was literally not only shifting the phase a lot, but also rising the whole impulse in the RX channel to such extents that any small signal from desirable object may become lost. ML take on this is that they are looking for small/fast signal changes in the context of slow and big as coil moves over them, primary reason why correct swing speed is rather important. Also, their RX line has about +/-1.6V (after the coil amp) of headroom, so any large ferrous object may potentially exceed/clip this, as a result, cutting off important details. In other words, perhaps, it make sense to distantiate the coil from the ground in certain conditions to get more headroom for the signal. I did notice this a while ago while detecting in tall grass, about 5-6" tall, and yet finding coin size objects 7-8" deep? Further looking at the scope, desirable objects mostly effect the very start of the RX wave signal, while all ferrous cause a significant shift and effect middle of the RX wave signal. It is also important to mention, I think, that it seems, that Nox TX strength and RX gain never change in analog domain, and perhaps digital too. The user sensitivity adjustment is merely an adjustment of the signal floor threshold. Lower it goes (higher sensitivity), more detail (and noise) it will start to process.

EL NINO, interesting. Is there a difference with different GB values? in multi freg or/and single?

The only pic I have at this moment, apologies if not too clear, the bend is under red cover (latex bike tyre tube 🙂 ) To be honest, this is my 3rd middle shaft because one of them snapped bending. I was using pipe bender. There is certain limit when aluminium simply snaps. Also those holes at the back, they tend to implode or give up 1st. Can't recommend trying it, breaks too easily. I also heated up the arm cuff and made it narrower. Standard it is clearly designed for Popeye arms

One other thing, most of places I go, GB would jump from 0 to 80 within 20 meters, so there isn't one setting to suit at all times. I do use GB tracking now and then, but could never confirm it does anything good or bad. Information about GB is pretty vague - what people say vs my experience: - tracking GB can iron out good targets - not my experience - tracking GB is too slow - I find it tracks better than GB manually now and then - tracking GB robs processing power from useful work identifying targets - probably true? - incorrect GB will limit depth - not sure, need more tests like in post above - high GB makes more false-positives on bumps - yes, is Nox running hotter on high GB? - GB is irrelevant in multifreq mode - possibly? - GB is important in single freq - never use single freq, so not sure

Thanks for that. Just have to add to this, read somewhere on ML papers, they do seem to have an automatic sensitivity adjustment outside user control, at firmware level, which, kinda, makes depth tests or any tests inconsistent. Hard to tell what else they do in the background.

Got 2 middle shafts, so bent one to an S shape - much better, feels more direct. I think ML should've made coil ears off centre or an s-shaft. Had a constant fatigue in the upper forearm, which is no more. It is the twisting of the shaft during swings that the arm needs to counteract causing fatigue, as much as I could figure it out...