Ground noise question

[DigDeep]

Can fluctuating signals (highs - lows/wee - woo) be from ground noise if the detector is not moving/just sitting on the ground. most of the areas are fairly mineralized. Or am I hearing other interference from microwaves - radar or whatever.

I am usually using Monos from a little Coiltek Joey to a Commander 18" and more times than not the Joey is noisier than the big 18". I also have the 11"DD coil and it is dead quite unless an airplane goes overhead.

But anyways I hear noise even when it is just sitting there on the ground. It is just about the same amount of noise as when I am swinging.

Thanks...

[little bill]

sounds like a loose connection or something.if your running an enhancer it sometimes becomes noisy, but at a stand still you shouldn't be getting much feed back. have your machine cheked out. litte bill

[DigDeep]

Everything is tight, I don't think it has a problem, been finding gold pretty regularly but just curios if anyone else hears this. BTW it is a SD2100v2. I am hunting mostly in Rattlesnake Canyon, Dale mining district and occasionally in the high desert. It is the worst near Randsburg. Also it is usually much quieter if it is laying flat on the ground and level, a little worse on slopes and really bad if I lift it into the air.. Maybe I should just shut up and buy a 4500 if I want quiet. LOL.

Thanks

[grubstake]

Could be the power lines at Randsberg, or planes from China Lake. Ground over that way is not too bad, its one of the only places I can run a mono on my 2200. But! there is plenty of trash in the ground in that area. Grubstake

[Guest sandtrap]

You sure can say that again, Grubstake.. 200 years from now, people will wonder why they only find gold with their Minelab 9995's. I picked it all up, and save it all , to prove it.

[FlakMagnet]

Hi Digdeep,

Most PI's will be much less noisy if you have the coil on the ground.

Your description sounds like EMI interference which is high in the El Paso's but surprisingly

sometimes it's pretty bad in the Dale too...all those planes on approach to LAX,

John Wayne and Orange County airports and the various military bases.

A 4500 is much better at handling EMI, but nothing eliminates it fully in our interference-laiden

environment.. The trick is to out-wait it if it's aircraft or tune with the coil on the ground if it's

high mineralization.

Here's a big one: the other thing that can do that, is if you have dirt between your coil cover and the coil.

It really pays to make sure if you have a coil cover on, that there is not the slightest opening

where dirt can get in. If it can, it will and the resulting tuning snafu is very frustrating to try

to chase down.

Anyway,

best of luck,

Flak

[nuggethunting]

Hello Dig Deep,

Sounds more like an interference problem. When the coil is flat on the ground, you shouldn't get much interference since there is shielding on top of the searchcoil. However, the minute you lift the searchcoil off the ground to hunt side banks and such, you will get a lot more interference. The searchcoil is like an antenna, and you will receive a lot more interference when you bring it of the ground. Normally, the bigger the coil the more interference you will receive.

You can also get Wee-Woo's and Static Spikes if the coil is just flat. Typically the static spikes are discharges. In dry, arid regions like the Southwest you will get much more of these. The searchcoil is sliding across the ground building up friction and then will eventually discharge giving you those loud signal spikes.

Some have used "anti-static" sprays to help elliminate the static build-up. While others have grounded themselves to the detector and then to the ground elliminating any difference in potential between the coil, detector, user and ground potential.

Take care,

Rob Allison

[DigDeep]

Thanks guys for the info, Maybe I should have it checked out. I was just out detecting again, I really took my time to tune it while the coil was on the ground and get it as quiet as I could and it was better than before but still am getting some noise. Here is my best description of the sound, it is usually a high high then the occasional low then high high and so on........ another observation I had is the more the wind/breeze blows the worse it gets. Also it tends to get better the more hours it is used, usually gets smoother after about the 4th hour of solid detecting.

Don't get me wrong it is not a eardrum buster just an annoying wiggle in the earphones.

Does this sound familiar to anyone with a 2100 or do you think my detector is busted. I purchased it new and it has been this way since day one.

[adam]

Sounds like EMI noise. Your coil normally will not make noise (due to ground conditions) when just laying on the ground. The coil has to be in motion to detect anything. Air traffic , power lines,other detectors, and other things cause "wiggles" in the threshold when the coil is not in motion. Usually you just "wait out" airplane noise (typically about 2-4 minutes) . When it comes to power lines you can tune them out as best you can, but may not be possible at all.

If you are under a popular air traffic pattern , you will have the noise almost constantly , and I would say move on to somewhere else. You will miss targets with that kind of noise.

It would be rare , but it could be a bad coil too, or even something else. Otherwise, we all deal with it.

You say you tuned your detector on the ground (that works) however ,try finding the most interference in the air around you, and try to tune out the strongest signals that way.

[nuggethunting]

Hello DigDeep,

Sounds like EM noise like Adam stated. The older SD2100's have the small tune switch which requires a small screwdriver to tune. Minelab finally revised that switch and placed an external 10-turn knob on the SD2100v2's. Tuning the older SD's isn't the easiest, but you might give it a try to stabilize the SD2100 you have. I've noticed sometimes it done miracles, while other times it done nothing to help.

Windy conditions can produce more EM noise from static in the air. I've experienced it here in Arizona for the last 15 years with the Minelab PI's.

Talk with you soon,

Rob Allison