Cody: Auto sensitivity

[Anonymous]

Hi Cody,
I've noticed that you like to use auto sensitivity. I've read conflicting statements about it; mainly that it tends to overcompensate for ground mineralization thereby causing you to run at a lower sensitivity (than you might otherwise be able to set higher if you were in manual)
My other question pertains to where you set the sensitivity while running it in auto. Does that setting set the highest sensitivity point the machine will run should it detect optimum conditions? The machine certainly runs a lot smoother in auto, especially at the beach where conditions can frequently change. I was just wondering if it's affecting the machine's ability to get the best depth.
Thanks,
Joe
By the way, while I've only gone out about a dozen times with it in the last 2 weeks, I've actually been making some progress with this machine <img src="/metal/html/smile.gif" border=0 width=15 height=15 alt=""> Did my first dirt digging the other night. While I basically cherry picked (didn't think I should practice on my church's front lawn <img src="/metal/html/smile.gif" border=0 width=15 height=15 alt="">), I was able to tell what I was digging up by the sound and the digital readout. I'm getting to know what a "good" signal sounds like. Now I just need to work on finding some deeper stuff. All in all, it hasn't been as frustrating as the first couple of times I went out. Been trying out a number of tips and patterns posted here and it's really been a big help in getting a handle on this monster. Thanks!

 

[Anonymous]

There has been so much posted if Auto or Manual sensitivity is best so I talked to the folks at Minelab. The converstion came down to use Semi-auto unless the soil is very low in minerals and there is little or no external EMI Noise. I wanted to talk to an engineer to find out what I could on how the circuit works as far as the electronics is concerend. Unfortunately the discussion had to be with the engineers "down under" so I forgot about it.
I use Semi-auto sensitvity at 28 for several reasons. I like to use the digital display and the <span style="background-color:#ffff00;">digital numbers are very solid with Semi-auto ON</span> but flicker bad when in Manual. This flickering indicates lack of stability and I am of the old school that thinks one way to get more depth is to keep the detector stable. There are times when I will run it on the ragged edge but not that often.
I tested a bunch of targets both in a test garden and when I would get a hit in the field. I can see no decrease in depth with Semi-auto ON compared to Manual <span style="background-color:#ffff00;">when actually hunting.</span> What I experience is much better performance. However, there are times when I have used manual. One situation was around an old tree where I just knew deep coin were down there so used manual mostly because I could sweep the coil at almost a crawl. When I got a deep hit I would check to see if Semi-auto would also detect the target. There were some hits I got in manual that I could not in Semi-auto. I dug way down in the roots to find a small piece of iron. The bottom line for me is Semi-auto is more effective in most situations which is <span style="background-color:#ffff00;">pretty much what the Owner's Manual indicates and the folks at Minelab I talked to were very positivity about using Semi-auto with the sensitivity as high as can be set WITH a stable threshold.</span>
I have Semi-auto ON 99% of the time and don't have any concern that I am missing anything by not being in manual. <span style="background-color:#ffff00;">It really is a user preference and which one we feel the most comfortable with in my opinion.</span> I really like the stability of the digital reading and threshold with Semi-auto ON. This is a real plus for me when using ferrous sound to pick coins out of the deep iron.
The EX2 is a great detector. At first it seems like a "beast" but then it starts to seem fairly simple after a few months use. It becomes very comfortable in a short time and the rewards are great when we start to find the old coins, jewelry, and relics. I picked it out of a total of about 20 detectors I tested to go with as my main detector in my retirement. All the other were great also but it is the EX2 that I constantly found and find deeper keepers than I did with the others and I really like the discrimination. I was really impressed with the Explorer, Sovereigh Elite, DFX, and Fishers. What really sold me on the EX2 is the discrimination at depth. I really like the way we can create patterns with so many notches to work with.
Good luck and don't get the preacher to wanting 10% of your finds.
HH, Cody

 

[Anonymous]

Cody,
I appreciate what you are saying. It takes real courage to recommend either Manual or Semi Auto sensitivity operation on this forum with all the controversy that it stirs up. I find that of the 8 or so Explorers users in my area that almost no one uses Semi Auto.
My question to you is why did you settle on setting the sensitivity to 28 in Semi Auto. What happens if you set it to 32?
Also, did we ever settle the question of whether or not the Explorer would adjust the sensitivity to a value greater than the number selected if you use Semi Auto? If it does, then what difference does it make where you set the value?
HH,
Glenn

 

[Anonymous]

Hey Glenn and all,
This subject seems to recycle itself every couple of months.
Whether you find more in the long run using auto or manual will forever be debated; seems that there are plenty that do well with either method.
But here are a few facts that you can easily verify. In Semi-Auto the sensitivity does go UP or DOWN from the set point.
To verify: Set the sensitivity to 1 then switch between Manual and Auto while swinging over a target. You will get much greater depth in Auto. Many people have tried this and found they need to kick up the sensitivity to around 16 manual or more to equal the depth of 1 auto. So yes in Semi-Auto the explorer will increase the sensitivity over the set point and increase it greatly.
The converse is also true. Under certain conditions you can be running Auto 32 and the explorer will decrease the sensitivity to the equivalant of manual 16 or so. You will loose depth when this happens. It really doesn't matter much where you set the sensitivity in Semi-Auto, it is just a suggestion and the explorer will adjust to where it thinks is best.
Most experienced users (except Golddigger) consider that left to its own devices that the explorer will sacrifice too much sensitivity in order to gain stablility. If you want the real deep coins you often have to push the sensitivity to the cusp of instability. The downside of this is that an almost unstable machine doesn't ID as well and you have to listen to much more noise to pick out the good signals.
Cody and others have verified the experiment that in high EMI environments the explorer will back off hugely on sensitivity in Auto. It is my belief that the explorer cannot differentiate between EMI and the normal signals you get from swinging you coil over the ground and will also hugely back of on the sensitivity in trashy ground, thus loosing depth.
I understand that the Minelab reps in the US say using Semi-Auto and Patterns is the way to go. That is how you differentiate your product from the competition and sell more.
Do a search for Mike Moutry's settings or Charles of Upstate New York for more opinions on this matter.
Chris

 

[Anonymous]

I found Mike's website very informative and that's who I was referring to (amongst others)... I'll be playing with both and see what I come up with. With my other machine, I've always tried to "push the envelope" and get the most out of it. Right now, I'll stick with what's easiest until I learn this dang machine <img src="/metal/html/smile.gif" border=0 width=15 height=15 alt="">
Thanks for the insight!
Oh, sorry to rehash an old tired subject, but I'm new at this <img src="/metal/html/lol.gif" border=0 width=15 height=15 alt=":lol">
Joe

 

[Anonymous]

I could hear internal circuit noise above 28 was the only reason. I called Minelab to see if they would explain what was going on with Auto and manual sensitivity. They told me they could not and to go by the Owner's Manual which was to use Semi-auto unless the soil minerals were light and there was little EMI and then only by experienced users.
I saw no way to resolve the questions about how they work so gave up on the discussions.
I have no problems with Semi-auto but do have stability problem in the areas I search with manual sensitivity. I like to see what the digital readings are and the readings flicker pretty bad if with manual sensitivity is set above around 20. So I set the sensitivity to 28 and use semi-auto and it works great.
HH, Cody

 

[Anonymous]

But..
I think no matter what your settings, unless completely out of whack, will still get 90% of the coins. It is in the really hunted out sites that pushing the limits pays off.
Chris

 

[Anonymous]

sorry to be so ignorant with the terminology but what is EMI?

 

[Anonymous]

Joe,
It is an interesting topic and many have discovered the same things through experimentation. There doesn't really seem to be a wrong or right way. The explorer pushes alot of information on the user and when you are starting out it can be overwhelming.
Much of the auto/manual or patterns/open screen issues are mainly about how much work you are willing to do with your BEDU (between ears discrimination unit-brain) and how much you want the detector to do. As good as the electronics are most feel that listening to everything the machine can tell you and then deciding is better than setting up the machine to not give you this information.
Chris

 

[Anonymous]

This is the term used for radiated interference that limits the ability of the electronic equipment you are using. An example is what happens to your AM radio station when you pass under the power lines. The FM stations are not so susceptible.
Hope this helps,
Glenn

 

[Anonymous]

Glenn, have you figured out what Minelab includes as ground noise? They mention EMI and ground noise as if they are different. I considered ground noise to be the snaps and pops that get through the digital filters but that would be from ground minerals for the most part.
HH, Cody

 

[Anonymous]

Cody,
I am not sure what is meant by "ground noise" but I have some thoughts about it.
EMI has a source that is generating noise. The most obvious is power lines. Another example is another Explorer hunter close to you.
I do not think that there is source for ground noise. It is just a product of mineralization in the soil. To be more specific it is the result of non-homogeneous mineralization. If the mineralization were constant, then the Explorer woould simply ignore it. If the mineralization changes gradually, then the Explorer can track and ignore it. It is when the mineralization changes rather abruptly that you get "ground noise" when the Explorer recognizing the aburpt change.
I could just be "blowing smoke".
HH,
Glenn

 

[Anonymous]

I don't think that is blowing smoke as I recall that being pretty much what I have read and now recall being told by some engineers where another detector is concerned. They don't say much about it in reference to the Explorer but if you read and talk to others it looks like ground noise is just as you describe. This appears to be very minor and from my experience and testing there is almost no problem with ground noise in the areas where I am searching.
HH, Cody