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interesting observation on E-Trac noise cancel

randy

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Jul 5, 2008
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Chester County, PA
So today I went back to a new site I hit for the first time yesterday, and noticed the clad quarters were hitting at 12-46 on the E-Trac, when they almost always hit 11-47 for me around here. This was amazingly consistent, as I dug 11 clad quarters today. Why is this I wondered, different dirt at this site -- then I remembered that noise cancel assigned me channel 4, when it almost always assigns me channel 9 or 10. I don't think I've ever been assigned channel 4 before, so I manually set it to channel 10, and the clad quarters sounded like clad quarters again, and hit at 11-47.

Then I hit a deep silver, giving me a CO of 45 with an occasional bounce to 46. Before digging, and being naturally curious, I manually changed the channel from 10 to 4, and the same deep silver gave me a CO of 43 to 44, with an occasional bounce to 45. Again, channel 4 rang lower than channel 10 on the same conductive target.

What I think is happening is that each channel assigns different frequencies, and then the signal processing software has to take the analog frequency response and map it to a digital readout and a tone. But, the process isn't perfect (possibly due to rounding or some other software issues). I'm no engineer, but I do know of alot of E-Trac'er who want to know the best channel to operate on for deep silver, and this little experiment indicates that it may matter, at least for those who rely on the numbers.

(And obviously, we're gonna dig all deep high tones regardless of the numbers, and like many E-Trac'ers, I focus on the tone rather than the numbers anyway, but I just felt like sharing this little observation, FWIW).

Anyway, the deep silver turned out to be a '46 rosie. Also pulled a 41S merc, 37S buff, and a 6gr Tiffany sterling ring, for 126 silver coins on the year, a personal record. Thanks for looking and HH. Hopefully everyone is able to take advantage of the cooler weather and nab some keepers.
 

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So are you saying lower the noise cancel to 4 or raise it to 10?

All I'm saying is that I think the channels act differently (or the software processes them differently). More tests are needed. Since I'm interested in silver, the test is to find a really deep silver in the ground, and test them all before digging, and see which one sounds the best, then use that.

I did this on an 8 inch deep silver a while back, and they all did fine, so it would have to be one a little deeper, just on the edge of detection. Its not the fairest test, as finding it initially is a bit different than being certain that it is there, but it is something to see of one channel is stronger on deep silver or has better TID than the others.

I have read elsewhere that channel 2 is the best for silver, but I haven't had much luck with that one myself -- when I'm in a slump I switch to channel 9 and seem to do better -- but this has pretty much been superstition, other than the one test above which didn't show much, I have never tested them side to side.

Since the E-Trac is a FBS type detector and so is the Explorer SE, you might like to read a thread I posted some time ago and my findings with the noise cancel channel #

Read here: http://metaldetectingforum.com/showthread.php?t=30253

This is a great post, and the sort of thing I'm trying to get at. Not really sure it matters on silver, was just throwing it out there FWIW.
 
Great post. Similarly this might be a tool to use in defeating red clay.

I wish Minelab had given us greater control over the frequencies in FBS, why not allow us to manually turn up or down certain frequencies? Would Whites use that ability to figure out their software? One could make it more sensitive to 0.5g gold nuggets, less sensitive to iron cinder slag, more sensitive to deep silver, I guess that we are just supposed to trust that their software can ground balance and do this in every situation better than we could...
 
Well I have noticed mine gives me about a 10 in most areas here and has given me a 4 in a couple of spots. Maybe I should try manually setting it. So please tell me are the lower numbers better or is it the upper end? Minelab doesnt explain it in the manual.
 
most times I don't even noise cancel, if I turn my etrac on and it is running smooth I don't do a noise cancel. I don't even know how to manually change it...lol
 
most times I don't even noise cancel, if I turn my etrac on and it is running smooth I don't do a noise cancel. I don't even know how to manually change it...lol

Because you live in Ohio, must be nice to find a dime 10 inches down and know it isn't a nail... Not here.
 
Interesting...so much to learn about more expensive detectors. Glad I chose more towards the beginner's market with my 350 :)
 
Because you live in Ohio, must be nice to find a dime 10 inches down and know it isn't a nail... Not here.

Well I live in Ohio and have dug a lot of "Carpenter Dimes" aka nails! Sometimes you know it is probably iron...but something just makes you wanna try! Dug enough keepers in with nails to make it hard to resist on those iffy signals!
 
Randy, that is very interesting. I'm gonna have to try that test here also. Nice job pulling out the silver.
 
I did some more experimenting with this today. I got a deep iffy signal, that I was pretty sure was a copper or silver. I was hunting on channel 6.

I went thru all the channels, and 2,6,9,10,11 gave me something I would dig. 1,7,8 were useless, no signal or maybe a threshold null at best, and 3,4,5 very iffy, to dig or not would have depended on my mood. Since I knew a target was there, it was tough to be objective on those.

2 and 6 suggested it may be a silver, 9,10,11 all were leaning towards wheatie, but there was a bit of bounce on all channels, and obviously it is hard to be sure on the deep ones. Anyway, turned out to be a wheatie on its side at 9.5 inches (measured, including 2 inches of grass).

I did try this test once before on a silver 8 inches deep, and all channels were fine. I know one target doesn't make a scientific test, but I lean superstitious on these matters (I've almost always used 9 or 10 anyway), so I'll be using one of 2,6,9,10,11 going forward.

FWIW, YMMV, and so forth. :lol:
 
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