Noise cancel, how do you do it?

[EZrider]

Question here guys. Ive always held the coil up 12" and steady. My friend bought a Safari and told me that he read to hold it on the ground? Is that the way Quattros ans Safaris are done? I didnt think the ground had anything to do with EMI?

 

[hershey1]

EZ: I have tried both ways several times and cannot tell any difference. Andy says one way and the other book say's opposite. I' am like a lot of people on that EMI. It is not in the ground where I hunt. My 2 cents. HH

 

[EZrider]

Hershey
Thanks for the reply. Thats kind of what i thought. I have had Andys book since getting my ET some time ago. I didnt see anything in there about having the coil on the ground. I guess the confusion came from the Quaterro book my friend got with his Safari.

 

[NebTrac]

You just push the little button that is farthest to the right..... sorry I just had to.

I've always held mine up off the ground, but I really don't have too much problem with EMI where I hunt.

NebTrac

 

[grumpyolman]

I think there are other issues other than just EMI. I think it also interprets the soil and its mineralization and includes that into data matrix for channel selection. You can't do that when it's in the air. Somebody once pointed out by asking where is the coil when you are searching. It's not 12" off the ground so why adjust it for that setting and then use it in a different position? If you believe what is claimed about the noise cancel, some who are successful don't just do it once and then hunt all day. They regularly ground balance. Even if it's not necessary, take the 30 seconds and take a look all around you while the machine is doing it's calculations and update your situational awareness. Jim

 

[EZrider]

I thing noise cancel and ground balance are two diffrent things. Unless im wrong and noise cancel is also a way of ground balancing these detectors. I always thought they automaticly ground balanced themselfs while detecting. I do noise cancle when in diffrent areas or adjust settings.

 

[kurt-ks]

Curious myself,one time I noise canceled with the sun-ray probe accidentally switched on and it chose channel 7-after realizing I did that I re-noise canceled with the coil in the same place(off the ground)and it chose channel 10? So I don't really know whats going on-feel like I need to know though,might help performance of the E-Trac??

 

[captn_se]

Strictly speaking for the Explorer and E-Trac series, there is no way to manually ground balance these machines. Ground balancing is automatically controlled by the machine.

And the only goal of the Noise Cancel feature is to get your machine to run at the best noise(EMI) free operating frequency(s) at any particular hunting grounds. EMI can be anywhere...above(Sutro towers, alarm systems, antennas, power lines, etc.) or below the ground(electrical wiring). EMI is a big problem at all the local city parks I hunt at. Sometimes, just walking an extra 50 ft in front of you can cause the machine to start to go crazy. Sometimes keeping the coil on the ground makes the noise go away, and upon raising the coil just a few inches off the ground or setting my machine on the ground with the coil slightly raised, the EMI just sings through the headphones. In this particular case, I like to raise my coil off the ground before I do a noise cancel, so that the machine will better detect the EMI, and select a quiet operating channel. Sometimes, I raise my coil off the ground and point it at a location that is causing the strongest EMI before I noise cancel. The only goal of noise cancel is to try and get your machine to operate at a quiet, noise free channel, so that your machine will function better, and you'll be able to hear what's in the ground better without the pesky EMI causing the machine to false. EMI is everywhere....don't assume you don't have any in your hunting grounds...

One thing I haven't been able to understand or figure out is whether strong EMI can affect the "auto" sensitivity setting of your machine. Not sure whether the falsing caused by EMI can cause the auto sens. to adjust to a lower value. Or whether auto sensitivity is strictly a function of ground minerals/high trash targets under the ground. If EMI can affect the auto sensitivity setting, all the more reason for the guys that hunt in auto sens. to be sure to noise cancel to best remove the EMI interference, and allow the machine to select and operate at a higher auto sens. setting.

HH,
CAPTN SE
Dan

 

[captn_se]

can affect the way the machine reacts to ground mineralization. It's called the "Ground" control in the Expert Menu. You've got a choice of two settings on this control: either Difficult or Neutral. Making the proper selection of this control can reduce falsing caused solely by ground mineralization. The manual demonstrates how to best choose which ground setting is best for your hunting area. Regardless of this control, ground balancing is still an automatic process controlled by the machine.

HH
CAPTN SE
Dan

 

[christopher-ohio]

The Infamous "How to Noise cancel" Question
Posted by: Andy Sabisch [ Send a Message ]
Date: January 10, 2009 07:16AM Registered: 4 years ago
Posts: 597

This question comes out on a regular basis and each time, it always gets a wide range of answers. Here's a few points to consider for the basis of your in-field practices:

1) Noise canceling is a requisite part of the FBS detectors operation. If you have an Explorer, E-Trac, Quattro or Safari and do not Noise Cancel REGULARLY, you will sacrifice performance . . . . . and that is a proven fact. You may feel it is "stable" but there is more going on with Noise Cancel than making the detector sound stable . . . . if you are in AUTO / SEMI AUTO sensitivity, it will remain stable but at a loss of sensitivity. 30 minutes is a max between Noise Canceling for me and if the ground conditions look like they have changed, I simply take 30 seconds and redo it.

2) Holding it on the ground of off the ground: Both methods have been discussed in different Minelab manuals over the years. The E-Trac's manual says "1 foot off the ground" and as Harry said, the Quattro's says "On the ground". They both operate on the same circuit (FBS) so no one thinks it odd that hey direction changes from manual to manual? Being part of the development team we saw that statement get added to the manual at the tail end and questioned it. After checking the resulting value at MANY sites - a dew times on the ground and them off the ground guess what . . . . there was no difference in the value selected except in a few urban situations. And then the point that was evident was the channel selected ON THE GROUND provided a tad better sensitivity in AUTO than the air. Why? Because one hunts with the coil on the ground and not a foot off the ground in the air!

There is more on the subject but if you do not Noise Cancel regularly and throughout the day or keep the coil on the ground, you may not notice any performance issues but you will not be getting the most the detector - any FBS detector - can provide.

Andy Sabisch



Edited 1 time(s). Last edit at 01/10/2009 07:18AM by Andy Sabisch.

 

[John LA]

The noise seen by the coil will be about the same on the ground, 12" above the ground or 3' off the ground.

 

[EZrider]

Thanks all for clearing this up. Some were mistaking that holding it on the ground was some sort of balancing.

 

[NebTrac]

This brings up a question for me anyway, here it is.

Has anyone ever noise cancelled in heavy ferrous trash and had the detector perform better or differently? I must admit I've never tried this yet.

Thanks,

NebTrac

 

[RandyNorthridgeca]

n/t

 

[Chris(SoCenWI)]

Dan,

There was an article posted on the Fisher forum by one of the Fisher engineers. He said sensitivity control was there ONLY to deal with EMI. We would all run at max 99% of the time if we could, but because of EMI we can't. So that is what auto sens does. And many of us feel it tends to be a bit on the conservative side. My big question has always been does hunting in trashy areas also affect the auto sens setting. I don't know if the machine can tell the difference between lots of EMI signals and lots of signals from swinging over targets in the ground. From what I am hearing from ETRAC users is that yes, in trashy areas the sensitivity gets turned down. And most of us would not want this.

Chris

 

[EZrider]

Dan,

There was an article posted on the Fisher forum by one of the Fisher engineers. He said sensitivity control was there ONLY to deal with EMI. We would all run at max 99% of the time if we could, but because of EMI we can't. So that is what auto sens does. And many of us feel it tends to be a bit on the conservative side. My big question has always been does hunting in trashy areas also affect the auto sens setting. I don't know if the machine can tell the difference between lots of EMI signals and lots of signals from swinging over targets in the ground. From what I am hearing from ETRAC users is that yes, in trashy areas the sensitivity gets turned down. And most of us would not want this.

Chris

Hunting in NYC parks that are 150 years old or better. When digging a target here you are going through a time line of trash targets. Not to mention power lines, underground lines etc. My auto Sens is always 20-22. Ther are some clear areas that i bump up to +3.

 

[Chris(SoCenWI)]

Done much detecting out in the boondocks away from EMI. Just wondering if it goes higher then. And then if you got in some trashy areas but no EMI does it stay the same?

Chris

 

[Ray-Mo.]

The auto sens. is very much effected by what is in the soil as well as EMI.If I run my E-Trac over cinders from old coal stove ash the auto sens will drop to as low as 1 or 2 but usualy around 8-10.Of course depth is not much different at auto 8 or man 30 in the cinders,about 3" max on a penny.A heavy carpet of nails will also cause auto sens to drop a bit as well.This can be a good thing as I get much better seperation in heavy trash with the sens lowered a bit compaired to running it at 28-30.

 

[EZrider]

I agree Ray. I feel that Auto Sens doe its thing very well. Even then te option to bump it up or down is a neat feature. The E Trac is such a soild machine that hunts well.

 

[synthnut]

I'm a newbie at detecting and EZ's friend ...We have discussed detecting together at length, and I am using a Safari ..... My thoughts on this are that since the coil is reading ABOVE as well as BELOW , and since it doesn't seem to matter , won't we be killing 2 birds with one stone so to speak by placing the coil on the ground ? ...The lower portion of the coil is picking up any EMI in the ground, and the top of the coil, exposed to the air , is picking up whatever EMI that exists in the air .....Again, this is just my theory, and what make's sense to me ..... BTW ...I am VERY grateful to EZ for his time and patience with me as he teaches me detecting .... I am that little kid that always says " but why" ? ....... That's how I learn !!!...... Jim

PS ....I am a keyboard player by trade , and played professionally years back , hence the name "synthnut " ......I LOVE the way the Safari sounds off on the various targets ....The different pitch of the ocillator is right up my alley !!.....Music to my ears so to speak !!...Jim