Speaking of detector depth

One might think that a paramagnetic target would be somewhat discernible since it has a slight magnetic permeability and a diamagnetic target has none. Perhaps you'd use two xmit freqs - one low and one high. At the high freq the non-ferrous diamagnetic target would exclude the primary magnetic field from the target and give a stronger -X signal. The paramagnetic target might give an inductive signal (+X) generated primarily from the low freq. That could give a bit of a delineation between the two.

Or perhaps, if aluminum and coins have similar resistive qualities, the paramagnetic aluminum would, being more inductive, have a longer Tc than a diamagnetic target. Probably not much difference though and probably too many variables involved.

Don't think we'll ever free ourselves from pull-tabs and other aluminum junk.

What we need is a scientific breakthrough that is completely "other". Nothing to do with induction-balance and sinusoidal waveforms. I want to see x-ray vision - in high resolution, down several feet, to visually discern target type by shape. Apparently the soil doesn't cooperate and attenuates short-waves and long-waves don't give the best resolution. Somewhere 'out there' is the answer.

You don't know..... what you don't know.

((( Paradigm-shift needed )))

Down and dirty those that dig find the goodies others miss...Quite apparent in beep and dig units and those relic hunters with shovels in the boonies.

With so many situations in the ground no matter how precise our meters and dials good finds will be passed over..

Still remember the early days when I wasn't as choosy and park hunted and ended up with 10 gold rings and a cigar box full of sterling silver rings religious medallions and such the first season. Have to admit that first year put in a lot of 10 hour days and had to buy batteries by the bulk so no free lunch and one has to work for the pouch fillers...

Hi,, Add some roundness to a ferrous & nonferrous item then everything changes again and don't forget the soil moisture content and the soil composition factor & it's ability to change things ....The sum of two or more items =????....My best discrimination tool is my ears and just knowing what my machines are telling me....Success in the field is not always depth related.... JJ

Interestingly, with Doppler radar, there is now a horizontal and vertical polarized wave transmitted. With this new technology it is possible to determine better the hydrometeor type by its shape, or determine that the returned energy is rather just a flock of birds or bugs. Produces more accurate radar products.

If similar technology were used and pointed at the ground (polarized waveforms), then perhaps we'd get a sense of the width and length of the target, which could be correlated to a database of known targets.

Then the round (X=Y) target would be determined to be a coin and the elongated nail (X<>Y) would be more obviously what it is - a nail.

Give it 10 years and people will look back at the induction-balance detectors of today and say "really? - they used to use those things to locate targets in the ground?" But then, I'm still waiting for my flying car and the jet pack I was promised in the 60's.

markg Wrote:
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> One thing not mentioned here is EMI and how it can
> change the detection depth of every machine to a
> certain percentage.
> An example is in order.
> This past summer I had the opportunity to compare
> detection depth between the Fisher F75, Whites DFX
> and V3i and finally the CTX 3030.
> In areas where EMI was not an issue each machine
> could detect with a certain margin of accuracy
> coins down to the 8" level with little difficulty.
> Now moving on to areas of medium to high EMI and
> over half of the machines mention could not detect
> a dime at 6" regardless of settings. Please keep
> in mind, before each machine was tried the others
> were turned off and stored over 50' away from the
> location. High EMI can change the detection
> capabilities of every machine regardless of brand.
> I won't go into the specifics of which did better
> or worse, but will say each has their strong and
> weak points. Just my thoughts on the matter. I
> love this hobby............

Spot on. Along with silent emi

Johnny........ good tangential thinking!

How come you never see a CZ-3D with the 10.5 coil in these depth test's? Even with the stock coil still a depth monster. I was out with mine the other day and nailed a 10'' Indian I know my E-trac missed and that was with the 8'' coil! I just bought a 10.5'' coil and as soon as it comes in will be back at the same spot as I know there is more.

What a proper CZ can do with the standard 8" coil.......... (in reference to depth).......... most other detectors can not do with a 8" coil or 11" coil.

I have to tell ya, the 8" coil on the cz surprised me a couple weeks ago, but not depth wise.

I was up in DanPa's neck of the woods a couple weeks ago visiting the in-laws. I believe I mentioned this area before.

Fifty +- feet behind the 18 year old house, there is a spring that flows out of the ground, down to the small creek. The area is loaded with all size square nails. Looked on the oldest map (1872) for a building there..and none. I've pulled, in the past, many LC's, a couple seated dimes, a half dime and a few IH's. I hit this area once a day when I'm up there and we visit about three times a year and usually stay two or three days.

99% of the time I use the 10.5" coil on the cz. This is the first I tried the 8" at this spot. I have to mention that I also covered this area with the f-75, 11" and the 5" coil.

Got set up with the cz, ground ballanced, sens 5, 0 disc as usual..... BAHM, first hole, 1830 something large cent 7"deep, hmmm how did I miss that all these years. Pocketed the coin and slowly swinging again, with iron grunts in every pass, then BAHM!! again, even louder...another large cent 3"down, deeply stamped with the name N. SEELY. How is this possible? I've killed this small area with the 75 many times over the years.

Hunted the rest of the weekend, going over and over the area, and nothing else......go figure.

I hate to beat a dead horse, but I have been adamant in all my posts about CZ's, in how the 8 inch coil is the BEST coil for that unit....EVEN ON A BEACH !

I know the 10.5 may be able to hit on coins on edge a bit better, the FZ12 being a tad bit deeper ( but does tend to ID some coins differently) and the 5 inch being able to sniff out a few more goodies in trash...but that trusty 8 inch coil always stays on one of my CZ6a's. And that is my primary if not always, beach coil.

And I have ALL four coils. Never use the 10.5 or FZ12 on the beach. The 8 inch always finds me good stuff, is easier to pin point without using the pin point button, and is a pleasure to swing, when the unit is mounted and a straight shaft, under the arm. Perfect balance and coil control with the 8 inch.

Sorry...the FZ12 is not for sale ! HA !

Therover, I remember you saying that a few times in the past. So, the fz12....not for sale? How much?

Correct............ the 8" coil on the CZ is 'max-Q'. It also does suit many hunting scenarios.
The 10.5" and 5" coil absoluletly has their place also.

IF I feel the need/justification for using the 5" coil on the CZ............ now-a-days: I will nearly always switch over to the F75 SE with the 5" coil......... especially if it is a nail infested area. Or.............. I'll grab the XP GMP.

Ozzie...if I decide to sell it, you have first dibs !

Ha Ha Ha, thanks therover.