Auto-Sensitivity: Is there really any reason to set it less than 32?

[N2Treasure]

I also tried to balance out the Explorer this weekend. It was backtalking me somewhat fierce, almost like electrical interference. I hit the manual sensitivity and backed it down to 22 and it was worse than when I had it in semi-auto. So Semi-auto for me!


Duane

 

[Derrelld]

This post is a great one to talk about...
I have always favoured manual sensitivity at 26.. Dropping it every now and then when conditions require.. To be honest i have never hunted in semi auto.. But i am sure going to give it a try tonight I will report with any interesting findings!
Derrell D

 

[Erik in NJ]

when we discuss this issue, and no one seems to have addressed it or its impact is the level of discrimination that you're using. Way back when I first started I used to use a lot of discrimination because all of the trash in the ground generated a lot of confusing signals to listen to. I used to run Manual (because they used to say it went deeper) at 28. As I started using progressively less discrimination I felt that I had to back it down to 24 - 25. When I switched over to Iron Mask with much of the screen open, I've found that Semi-Auto 32 really makes the machine run so much smoother and greatly reduces the high-chirped falsing which is unpleasant to listen to and really starts to get on your nerves after a few hours of hunting.

Folks have weighed in on their Semi-Auto/Manual sesitivity settings, but maybe we should also be mentioning the level of discrimination we are using. I'm using IM 22, which I believe is what Bryce is also using.

 

[Chris(SoCenWI)]

Erik,

The reason I wanted you to do the manual 1 test is to see that in semi-auto the machine is really pushing the sensitivity up to an equivalent of 16 manual or so. If you are running at semi auto 32 and the machine thinks that is too high it will push it down to perhaps the equivalent of manual 16 or so. My and others experiments showed semi auto could vary as much as 12-16 notches.

So if Bryce is saying he is can't run above 26 auto it really means he is running around 14-16 manual. And this is probably not an unreasonable number for in-town hunting.

Discrimination:

A few years back I was out hunting and ran across another explorer user. He wasn't finding diddly; had most of the screen blacked out except for small learned in windows. He could not get a signal from a coin two inches from his coil. I opened up the screen and immediately saw the cursor bouncing about and the pinball machine on acid sounds. He had the sensitivity turned up way to high and the machine was going nuts, but with all the discrimination all he heard was nulling. So yes, when you open up the machine you are more aware of the effects of EMI.

I'm pretty sure that the autosense doesn't have much or anything to do with mineralization; but has everything to do with electrical interference. This was experiment #2. Go in your house, turn on the computer and TV and vacuum cleaner. Now turn on your Explorer. Open up the screen. At 32 semi auto it is probably going nuts. Start bumping down the sense in semi-auto until it gets stable. You may have to go quite low. Now start at 1 manual and bump it up until you start to hear some chatter, then bring it down a notch or so. Basically get it as stable as you where in semi auto. Subtract the manual number from the semi-auto number, I usually get 14-16 difference. Somewhat subjective, but it gives you an idea of how much the machine will back off on sensitivity to get a stable threshold.

And this works, the semi-auto sees the electrical interference and drops the sensitivity down to get a stable machine. Now tell me when you are swinging your machine how many hits and noise you get. How does the explorer know this is targets and not electrical noise? It probably doesn't. So it turns the sensitivity down, maybe way down. But junky areas come and go quickly; how quickly does the algorithm crank the sensitivity back up.

Now with the Etrac we can see where is it at. I've heard that people can see the sensitivity vary from the set point when they hit trashy areas. Hoping someone will run the above experiments with an E-Trac and see if they really changed the algorithm.

Basically running in semi-auto is like disconnecting your speedometer cable and painting the number 32 on the dash. It might make you feel like you are going fast but in reality you have no idea. Generally in manual you can turn the sensitivity up a least a few notches from where semi auto would set it. And I know this makes a difference. When I am detecting under power lines and have to turn the sensitivity down I never get the depth I do hunting out in the country away from sources of EMI.

Chris

 

[Chris(SoCenWI)]

Thats a difference of 11, and I believe it is probably worse than that.

Steve, can you crank it up higher than 21 manual without it going batty and get a better signal? Sounds like you might have some EMI noise sources nearby. Should be able to get signal at 8" on all the coins unless you soil is very mineralized. I don't buy the halo effect arguement, at least for silver coins. Do you often find coins at the depth in undisturbed soil in your neck of the woods?

Chris

 

[Hotcz70]

Just like when I vary my sensitivity up a couple of notches....If I open Iron mask up to 23 or 24...deep rusty iron starts to mimic deep silver to my ears...and more nails end up in my pouch
Those little falses and chirps that I know are iron just seem to turn into more "diggable" chirps.

If I close it to 21 or 20....my SE won't hit deep silver in a null like I want it to

For me...my ears...and my soil conditions...IM 22 is one setting I truthfully never vary from.

I know some guys who hunt conductive with iron mask much more open...from 28 to 30 or so....and they do very well.

For me though...I've found the ticket that works for my ears. The setting of IM22 allows me to be able to tell iron most of the time. Sure I dig some iron crap...but if I do...it was my fault and I already knew it was an iffy hit before I dug it.

What it boils down to for me is that the setting allows me to hit a coin while my SE is nulling...and also makes iron hits pretty much sound like iron hits instead of deep silver.

If I vary by one # either way....I'm screwed

 

[Steve(OR)]

If you have the time it would be interesting to start with a setting of 1 and step up 3 or 4 clicks per trial.

Yep... I just did it with the '64 Half (being the biggest target), with these results:

Manual 1 == Threshold only
Manual 3 == Threshold only
Manual 5 == Threshold only
Manual 7 == Threshold only
Manual 9 == Threshold only
Manual 11 == One little peep (maybe - pretty bad)
Manual 13 == One little peep
Manual 15 == A few peeps now - and a couple good tones
Manual 17 == Quite a few good tones now, among the peeps
Manual 19 == Mostly good tones now
Manual 21 == Mostly good tones now
Manual 21 == Mostly good tones now
Manual 23 == Mostly good tones, but mixed with some false/crap/nulls

(NOTE REGARDING MY SETTINGS: Running Conductive sounds with 24 Iron mask. This point - about Manual 23 - is about as high as I can go without the threshold going nuts (or nulling out) all the time. With Ferrous sounds and AM, it's worse - at least today it was. I had a stable threshold about Manual 19, but the tones weren't nearly as good as with Conductive)

Manual 25 == Still getting good tones, but the threshold nulling about half the time
Manual 27 == Good tones are fading into the nulling/crap - threshold nulling about 80% time
Manual 29-32 == The threshold nulling is nearly continuous, and very sticky. Some good tones, but probably falsing too

Semi-Auto 1-28 == Threshold only
Semi-Auto 29-32 == Circling the target, I got maybe one good peep, nothing that would be considered a good tone.

I've never gone through the whole range before - I am surprised at some of the results.

SCM

 

[ngrelic]

Thanks Steve, really interesting test results.

Barry

 

[Steve(OR)]

Thats a difference of 11, and I believe it is probably worse than that.

I think you're right - probably closer to 15 (see other results post).

Steve, can you crank it up higher than 21 manual without it going batty and get a better signal?

I normally hunt with Manual 22, on the average. I got to 23 on my test today, but it was getting hinky. Any higher, and it starts to sound like the "Mayberry Marching Band" (for those "Andy Griffith Show" fans).

Sounds like you might have some EMI noise sources nearby. Should be able to get signal at 8" on all the coins unless you soil is very mineralized.

Yes, there is some EMI (power lines) around, but not as bad as some places I've been. Maybe it's worse then I think?! As for mineralization - it's definitely higher in this part of OR. I remember reading a post from Charles(UpstateNY) after he spent a week out here, suggesting how to deal with the 'black sand infested soil' in Oregon.

I don't buy the halo effect arguement, at least for silver coins. Do you often find coins at the depth in undisturbed soil in your neck of the woods?

Not really - generally, most of the older coins I've found are in the 3-6 inch range (of course, we don't have the history here in Oregon like you do east of the Rockies). However, it has been frustrating as I believe there should be good, deeper targets at the places I hunt... am I not recognizing the 'deepies' - or are they just not there???

SCM

 

[Erik in NJ]

Now we are getting somewhere with some real data! It would be cool if we could locate someone with a real old test garden to repeat the experiment. I'm going to put your data up in Excel....would it be possible to repeat your experiment with the dime and quarter? Hey, thanks for putting the time and effort into recording these data!

 

[Erik in NJ]

Hi Chris,

I read your post with interest, you make some good assertions, but I have a few comments on some of your deductions which I'll post later when I have a little more time -- not saying that you're incorrect in making them, just a few questions and observations.

The main flaw I see right now is that according to Steve's data, if his machine was in Auto(1) it should have easily picked up the coin, bcause you say Auto(1) == Manual(16). In Manual(16) he easily picks up the half, but in Auto(1) he gets nothing, but threshold. I haven't tried your experiment in the air yet because my SE crapped out this past weekend, but maybe someone else here can do the air tests and post the data. I want to put it all in an Excel spreadsheet with graphs that I'll make available to anyone that wants it here.

 

[CT Todd]

outstanding post thread this is why I come to the forums

 

[Steve(OR)]

I want to put it all in an Excel spreadsheet with graphs that I'll make available to anyone that wants it here.

Hey Erik - I like the idea!

Let's keep in mind some of the other variable factors as well:

• Location/soil conditions >> i.e. mineralized soil (very high -to- none); moisture content; etc...
• Machine differences >> S / XS / II / SE literal differences, not to mention coils, not to mention actual component differences (i.e. maybe I have a "semi-dud" SE processor/chip/PCB and don't know it??)
• Users >> Maybe my "beep" or "peep" could be a "dig me" to ChrisWI or JamesND or ErikNJ???
• ???

However, there is no denying that Semi-Auto for ME just does not produce like it does for, lets say Bryce. Even so, can the differences be calculated or measured quantitatively???

SCM

 

[Chris(SoCenWI)]

I don't think in Semi-auto it will vary over the whole range of sensitivity. Set at one or two auto-sense may crank it up to 15-16, at 32 it may go down to 15-16.

Steve's data makes sense: The machine thinks that the ideal setting is say 17, less than the 21 or so manual he needed to get a signal. At sense 1 he won't get a signal because it won't climb high enough, and if he sets it higher it will just detune until it gets back to the 17 it deems suitable. Perhaps he or someone else can bury a coin in nice soil out in the country side where you can crank sens up to the high twenties manual, then see if semi-auto will climb that high.

I've played with both semi and manual. There are times when I can get it with either, other times not. Just don't know where sense is at on the older explorers.

I've much more to say on this, but not now.

Chris.

 

[Erik in NJ]

Steve wrote:

Manual 17 == Quite a few good tones now, among the peeps



Don't take me seriously -- I'm half joking this is a great debate........I'll even give you my phone number so we can shout at each other!

 

[Steve(OR)]

Steve wrote:

Manual 17 == Quite a few good tones now, among the peeps

Well, I was going to make some silly, off-color comment, like "... I's gunna drag me peeps ova'ta Jersey and do's sum detectin' on yourz heyad!" - al la Herbert Kornfeld.

But, I figured I'd better let it slide...

 

[Erik in NJ]

he's startin' to bend the truth just a little bit if ya know what I mean.......but Steve I do like ur Jersey Boy accent......u wanna piece of me or what?!?!

 

[Erik in NJ]

If the car would drive itself then I wouldn't mind painting the max speed that I select on the dashboard.

I guess the better analogy is a manual vs. automatic transmission. I don't bother with manual, because the automatics in my cars are pretty darn good....perfect, no, but sure beats having to do all that work. Even better analogy is the trans in my Range Rover and where I can drive in automatic and shift manually IF I want to.

 

[Steve(OR)]

Perhaps he or someone else can bury a coin in nice soil out in the country side where you can crank sens up to the high twenties manual, then see if semi-auto will climb that high.
Chris.

Actually, last year I got out of Portland and down the valley a bit, and got to run at Manual 28 - but did not experiment with Semi-Auto at that time (... as I was too busy trying to find ANY kind of coin to beat my buddy and his $99 JC Penny's Bounty Hunter that he swings like a golf club 15 inches off the ground - AND HE STILL found a 1903 V Nickel that day! ... and I found only junk/clad with my "state-of-the-art" equipment)

Anyway, I think my new "deep" strategy next time out (maybe tomorrow) will be to visit my ol' standby 40's high school and dig everything that sounds even remotely good, but has a depth of at least 7 inches. Something's gotta change...

Insanity: Doing the same thing over and over again and expecting different results

SCM

 

[Erik in NJ]

Anyway, I think my new "deep" strategy next time out (maybe tomorrow) will be to visit my ol' standby 40's high school and dig everything that sounds even remotely good, but has a depth of at least 7 inches. Something's gotta change...

I use it quite often, but dig at a minimum of 5-6 inches....you might miss a few shallow silvers, but who cares....dig all quarter hits at all levels as they might be halves or dollars....very often it's the law of diminishing returns that takes over....you can probably spen 10 years hunting out a place, but is it worth it????