Auto Sensitivity question. Why not just use manuel sens. like explorer and run as high as you can stand it?

[jtalley007]

I'm sorry if this has already been answered but it seems that since we know with the explorer EMI really affected the sens and EMI is everywhere why not just control the sens. instead of letting the machine. Are we just experimenting or trying to give up some control to make it easier to just turn on and go, just curious. I may need to download a manuel and read up on it myself. I really appreciate all the posting and the fact we have this E trac forum to do it. I also would like to know if there are any guys in Virginia around Culpepper in that hot ground that have tried the E trac. Really enjoyed Charles, Bernie and the other guys posts. Thanks

Jerry Talley

 

[digitrich]

Seems that is the way to go with this machine, manual pushed as high as possible. Some of us get a great deal of failsing with that set up and others swear theirs runs as quiet as a church mouse and have the finds to prove it. So, I guess it would depend on your soil and your machine.

 

[coinnut]

Most of us already use manual sensitivity, but the question is how high? One thing the auto is showing us is how different the computer adjusts the sensitivity in one particular site!! I would have never thought that the sensitivity would need to be adjusted that often. So if we pick a manual mode, we may be over doing the sensitivity and hurting ourselves. Too much sens and it seems to false and chatter more. I'll take that any day over lack of depth due to too little sens. In one of my sites, i had auto on and it switched from 15 to low 20's down to 4, This was due to going from field to dirt to chopped up gravel road. It appears that manual will probably be my primary mode of operation. If I use auto, it would be auto+2. Just my thoughts on this though.

 

[digitrich]

may times I can push it 4 or more above suggested and still maintain stability.

 

[Ray-Mo.]

tHAT IS BASICALY HOW I RUN MINE.AS HIGH A MANUAL AS IS STABLE OR CLOSE TO IT,RAY.

 

[Jeb NWR]

Jerry, WHY ,are you trying to beat the Detector ? What is your main aim ?
The detector (E Trac) is able to scan the ground to enable you to run at a sensitivity the detector concludes is the right sensitivity for the ground being searched. You however appear to be saying, " I`m not listening to what the Detector is telling me, my main aim is to make it do what i want it to do , and that is RUN HOT NO MATTER WHAT ! ". Why man ?
What`s the matter with some of you guys out there that seem to have this urge to run your detectors as Hot as you possibly can regardless of the Mineralisation or surrounding things that will affect your Detectors workings. IE Pylons.
The E Trac will tell you in Auto what it deems the soil mineralization is and what sensitivity it deems is appropriate . You can even up that by +1 ,+2, +3, if you want to play safe. Why this urge to discard what the E Trac is advising and go at it like a Bull in a China shop with Sensitivity whacked up in the Sizzling Stratosphere. ?
No wonder there are so many guys out there struggling to get to grips with detectors. I think They try to run before they can walk mostly.
PS do you have ,and use an E Trac , If not, why ask ?
PS i`d give this same answer to the question if it was aimed at an Explorer.
Running flat out Red Hot is NOT the best policy, especialy in difficult ground . Yes you will probably still detect Surface fodder and coins or artifacts that are readily available within the first few inches. But you will not detect the Coins that do not readily give themselves up easily .

 

[jtalley007]

What I have always found is our brain is much smarter than a computer. The if the auto sens. was just based on the ground then that would probably be just fine but with the explorer anyway EMI from power lines, storms, cell towers or anything would make it go way down. It appears there are other guys that hunt the way I mentioned anyway letting their ear tell them where to set it. Some used to swear by auto on the sovereign but the depth in that mode was a joke. On the explorer it did work pretty well if you were way back in the woods with no EMI but I did some experimenting digging relics and on the really deep targets I would get in manuel that barely came through, would disappear in auto every time. This meant if I would have hunted in auto I would have missed them. Keep in mind I am in Virginia hunting places that we hunted back in the early 70's that have been pounded and the only stuff left is over 12" deep, some places in the 14" range and that is the only reason you can even find a bullet. There are places here that are hundreds of acres that were covered with civil war troops and it is hard to find a relic there any more. I have also found that you have to run any machine in these places as high as you can putting up with some falsing or you find nothing. Again, I appreciate the feedback.

Jerry

 

[MattR]

Sound. logical, comment Jeb.

In fairness to the 'hot' guys, most of us do push our machines and rarely check the consequences to determine what it is we are gaining or loosing.

Often, as the old saying goes, "We make a rod for our own back".

How many of us upon locating an apparently deep target found using a 'high' sensitivity, then take a few moments to check at what lower gain we can still locate the item?......Or better still check it in Auto at the touch of the pad?

All food for thought, and informative. It may even confirm the 'run-it-hotter' attitude.

Regardless of what we do, the ground conditions and local EMI, will of itself regulate your machine's abilities to find.

It must be realised, that the detector's ground monitoring circuitry, is working on an 'average value of the past ground's history'.

That is, 'A mean value'. So in fairness to the Hot Brigade, their approach is more biased to 'anticipating-a-break-in-the-fog' approach.

Let us just contemplate realities for a moment.

Assume we are hunting in 'normal ground'. That is, somewhere that doesn't reduce our default Auto sense setting (i.e. 16).

In such circumstances, our E-Trac should easily detect a 1 inch diameter coin, laying flat in the soil, at six inches.

In the absence of external noise, that same target at twelve inches, would require a sens level of 28.

Above 28, I suspect there is nothing to be gained because you may encounter the unit's internally generated noise, especially if operating in elevated temperatures.

Conclusions?

Be happy doing your own thing. If you can learn something from your mistakes......then that's what counts.

Share your thoughts, and we too may become a little wiser, due to your efforts.................MattR.UK.

p.s. I had a 'learning' day, yesterday. Hard, clay based soil, just cleared of potatoes.

Ridge to furrow depths of 12 to 18 inches. Tough, chattery, difficult to scan in a normal manner. Tried many combinations of mode and screens,

Found plenty of targets, and chased as many rainbows.

I'm learning all the time, but realised that there is no 'magic-formula'.

I arrived late at the site, so it had already been hit by the club members with mainly Minelab Explorers.

But there was the age old reality proving itself with every find that I made, in their footprints.

You can't 'do it all', that well that others can't come behind you and still find their share.

That is reality, and not a criticism of anyone.........Enjoy you favourite hobby....Matt

 

[Jim upstate NY]

I believe that auto drops it to be the most stable it can be in that particular ground, which isnt necessarily the best setting just most stable, I think they do this for beginners, as a matter of fact I think a lot of the changes on the etrac are trying to make things easier for those that dont like programming and settings, thus all the factory presets making the etrac the most stable it can be. and I also believe thats why they lumped most of it all in the 12 ferrous range... less numbers or screen areas to remember I guess.. I dont think we will ever get an answer to why they changed the way things are reported.. had to be a reason.. we can only guess.. I am hearing since it isnt patented they dont want to give out proprietary info... holy mackerel.. a simple thing like if we didnt do this it couldnt do this would suffice for me... if its impossible to have ferrous audio because of falsing or the way it processes that info now OK, sure would be nice to get an answer to all these questions other than how you should set it up like we say and shut up and be happy cause its not an explorer


Anyway what I do is hunt in manual mode, when and if I get a deep target I just try different sens settings before digging.. switch to auto to see if it still hits solid, adjust manual up and down till I get the best response and leave it there for that area.. of course that only works if you can get a deep target.. dont forget to dig the target if it ends up not being deep or not a coin sized target do it again on next deep one.. I have seen many times on deep ones that switching to auto loses the signal.. at least on the explorer, I assume the etrac will do the same.. so far nothing so deep to tell.. at the same time if your in bad or iron filled ground you dont want to over power it either.. in which case even shallower targets can give you an idea of what the limits are by playing with sensitivity settings till you get what you think is best response at the highest setting before digging.. I keep bumping it up till its unstable but still a good signal then back off one... Auto definitely affects depth, even Minelab must think so or they wouldnt have added that auto limiting feature of + or -3.

the highest auto setting I have seen so far is 20, and that was good clean ground I know I could and hunt higher in and remain as stable as can be..

 

[Jim upstate NY]

I read your reply after posting mine... the thing is on the etrac, you get falsing in iron no matter what the sens settings, as a matter of fact sometimes in auto its worse because its such a soft false or its adjusting while you sweep over it.. which stops me in my tracks to have to recheck the signal a few times before moving on..

So far to me the etrac is more stable than the explorer as far as interference goes, very little falsing from ground or EMI, or bumping the coil.. but much more susceptible to iron falsing.. I am slowly getting it set to where it doenst drive me nuts, and hopefully eventually get there and not worry much about masking.. I am believing that the processing in iron is much faster than the explorer.. and thats generally what you get when you have a machine thats fast in iron.. chatter.. it has to be able to hit on the iron a little or it will mask out good targets.. F75, the Musky etc they are fast in iron, but you get a lot of chatter..

I had mine running pretty stable in it yesterday and still popped out a few things in some pretty pounded spots, even with all the disced out part of the screen .. so its working..
the funny part is I am thinking now that the explorer will be my choice in parks, and as much as I hate the changes they did in ferrous, that the etrac will be my machine in iron or at least the cleanup machine..

The etracs ID is faster but it also still reports the last target seen, so if your in trash its still hard to get a good reading on the target your after.. I find myself lifting the coil off the ground just as much as I did with the explorer, and I feel the explorer has a better ID system in smart find, (well at least more variability on targets) making it easier for me to use in non ferrous trash.. will see after I use this more... wish I had some new sites with more targets though.

 

[jbow]

I have had targets completely disappear when I switched from manual to auto and my auto generally runs 18-20, that puts +3 over 20 most of the time. However, only one of the three channels will be running at that level. The other two will be lower and one will usually be considerably lower. Manual puts all three channels at one level and if it is running fairly stable... why not use it that way?

You realize that some mach8ines are handling a high manual pretty well and others are not handling manual well at all, even fairly low. I can run mine 25 to 27 in most places. If I run 25 in conductive/multi... then I have to check a lot of hits, mostly falses... but it's not too hard to quickly tell that they are a false. Auto is smooth, but as with the SovereignGT, you will miss things in auto. What you will miss are the deep targets that you really do not want to miss.

I will make a point to check my targets the next few days with auto to see how many I would have missed by running in auto and what they are and how deep. That way i'll know for sure about this. I'll post my findings.

Julien

 

[Rigit]

I have noticed that most in the US are reporting Auto Sens running at below 20 so I kept an eye on what mine ran all day Sunday, most of the time 25-26 just the odd time dropped down to 24.

I was on red coloured slightly clay soil that was moist but not clinging to my boots, one thing that could be causng big differences in auto is that most UK detectorists have been on 6" stubble for the past few weeks and only now are getting the coil right down on the ground.

Keep the posts comming its all helping us to see the bigger picture.

 

[Charles (Upstate NY)]

If the E-Trac is like the Explorer (very likely) the machine transmits at 100% power and receives 100% of the possible return signal regardless of sensitivity or any other setting adjustment you make. It is not possible to reduce the transmit signal to say zap the ground less aggressively.

So all you are doing by adjusting settings on the machine is filtering out and/or boosting parts of this recieved signal. The ORDER in which these filters and boosting (gain) are applied is absolutely critical. One of the best things Minelab could do for us would be to tell us the order in which these apply.

For example lets say sensitivity is processed before gain. If you crank your gain to the max boosting even the tiny signals to a loud level then I have seen people back off their sensitivity to calm the machine down. But if there is a deep silver coin that is only audible at a sensitivity setting of 26 and you reduce your sensitivity to 20 what happens? Cranking the gain to 10 cannot boost a signal that has already been filtered out by lowering the sensitivity to 20.

So tweaking for depth, its an art form requiring some balance and attention to the order in which you apply your settings. If you crank your sens to max and the machine is going nuts with high tone falses you either can't hear the forest for the trees or you end up backing off your gain to deal with it. I have dug deep silver with my Explorer gain on 7 that was pretty faint, I nearly missed some of these and would have with my gain at 6. I may have missed some that required my gain at 8. But then site conditions with my gain at 8 produced abundant high tone falses so I had to strike a balance.

The E-Trac introduces new filters which will require some testing to sort out. The best approach might be marking some deep targets with an Explorer, then tweaking the E-Trac settings for max depth/strongest signal on those targets.

Charles

 

[Rigit]

If the E-Trac is like the Explorer (very likely) the machine transmits at 100% power and receives 100% of the possible return signal regardless of sensitivity or any other setting adjustment you make. It is not possible to reduce the transmit signal to say zap the ground less aggressively.

So all you are doing by adjusting settings on the machine is filtering out and/or boosting parts of this recieved signal. The ORDER in which these filters and boosting (gain) are applied is absolutely critical. One of the best things Minelab could do for us would be to tell us the order in which these apply.

For example lets say sensitivity is processed before gain. If you crank your gain to the max boosting even the tiny signals to a loud level then I have seen people back off their sensitivity to calm the machine down. But if there is a deep silver coin that is only audible at a sensitivity setting of 26 and you reduce your sensitivity to 20 what happens? Cranking the gain to 10 cannot boost a signal that has already been filtered out by lowering the sensitivity to 20.

So tweaking for depth, its an art form requiring some balance and attention to the order in which you apply your settings. If you crank your sens to max and the machine is going nuts with high tone falses you either can't hear the forest for the trees or you end up backing off your gain to deal with it. I have dug deep silver with my Explorer gain on 7 that was pretty faint, I nearly missed some of these and would have with my gain at 6. I may have missed some that required my gain at 8. But then site conditions with my gain at 8 produced abundant high tone falses so I had to strike a balance.

The E-Trac introduces new filters which will require some testing to sort out. The best approach might be marking some deep targets with an Explorer, then tweaking the E-Trac settings for max depth/strongest signal on those targets.

Charles

Charles you are right on the button, I found that by taking the time to get the volume limit and volume gain set up to a sensible level I was able to run with targets comming in clear and loud enough, hile falsing was a lot softer.
I think a lot of new owners are spendingto much time trying to the ET at higher sensitivity before they have mastered setting the volume limit and gain settings. perhaps it would help if we wher to post some of our saved mode files, I will upload my Sunday settings tomorrow.

 

[jbow]

I think that they do not know a lot of things. Surely they know the order but I think they don't know a lot of the ways things react with each other. I think they got this technology all into the package with whatever field testing they could get done and released it. I think a lot of the why and what are things we will have to figure out. I hope Andy's book will help a little but if it doesn't come soon we will have it all figured out ourselves. especially now that you have one. I wish I could come to NY and hunt with you but alas... Georgia is a long way away. If you ever come to the Atlanta area you better let me know...



Julien

 

[jeff & Maria]

So a adjustment of preamp gain is having a more of an affect than the sensitivity.

 

[jbow]

Are you saying that in ideal conditions you should run the sens and the gain as high as possible? Like, if the ground is pretty good and for instance, you find that you can run the sensitivity at 27 manual and things sound pretty good. Then you find that you can turn the gain on up and it still runs ok, with minimul falsing... is this good? Do you do your best to estimate the maximum depth of good targets and, in the above scenario, set the gain so that targets at that depth give a faint but good signal?

Other than the technical talk... what is your thinking when you get to a new/old site? What do you set and in what order?

I wonder if anyone has tried calling Australia and speaking with Bruce or with some ML engineer about some of these questions. I would be willing to make the call if I had a list of questions.

Julien

 

[digitrich]

I think that is the ticket right there providing we could get a hold of him.

First question......Noise cancel on the ground or in the air?

In what order do the filters work in? Sensitivity, gain, fast or deep, dense or low trash, difficult ground or neutral?

Would wrapping the 5 pin connector in the upper shaft with electrical tape (on all the Explorers) be a good idea for shielding purposes or does the machine need the metal of the five pin to touch the metal of the upper shaft for grounding purposes?

Should the ETrac be getting less than, equal to, or greater depth than the SE?

When in deep, does the signal from deep targets just get amplified in volume or does it also get lengthened, like in audio long, only to a lessor degree?

On the ETrac, is it possible for Mine Lab to update it and or diagnose it through the USB port?

Have they considered given the machine the ability of having a low ferrous tone report option say above ferrous value 21 while still in conductive tones. In other words, while still getting all the current conduct tones (in conduct sounds), any ferrous reading above 21 would give a low tone. In effect giving one the ability to hunt in all metal with the ETrac.

How about a true audio only discrimination option? So what ever you disc out on the smart find screen doesn't report audio (no tone, no null) but instead displays on the smartfind so you know it's there, but you don't have to deal with the null? No sound, just display. With an auto latch pinpoint, so that the machine tries specifically to pin point the weaker "accepted" target instead of the stronger signal; "rejected" iron?

Yeah, I have got at least a dozen questions for Bruce.

Maybe we could post them all here and have our most eloquent Charles write him an email labeled from all of us at the Findmall ETrac forum and see if he answers I think he would answer most questions that didn't infringe on any sensitive information. We will never know unless we ask, right

 

[jbow]

Would wrapping the 5 pin connector in the upper shaft with electrical tape (on all the Explorers) be a good idea for shielding purposes or does the machine need the metal of the five pin to touch the metal of the upper shaft for grounding purposes?

I have never heard of that... tell me more please.


Maybe we could post them all here and have our most eloquent Charles write him an email labeled from all of us at the Findmall ETrac forum

Good idea..

Julien

 

[digitrich]

I had a site I was getting to much EMI and I tried wrapping the five pin in the upper shaft with electrical tape and it seemed to help. But then later my dealer told me he thought that the contact of the metal 5 pin to the interior of the metal upper shaft was for grounding purposes and maybe not a hot idea insulating I kind of think, if it was for a grounding purpose, wouldn't the 5 pin need to touch the metal shaft constantly? When that five pin touches the upper metal shaft, I would think that the entire shaft would become a very large electrical antenna. Who knows?