Equinox IDing silver coins as iron.

If this has been addressed before, I must have missed it.

I put a stack of five silver half dollars on the ground and was surprised to discover that the Equinox would not pick it up unless the coil was at least eight inches away. At a distance of eight inches or less, the machine went completely silent and read in the negative numbers. A stack of four halves would go silent at a distance of six inches. In All Metal, it gave a low tone as if it was iron. Three stacked halves were not a problem and gave a nice clear high tone, even up close.

This is important to remember when looking for large spills or caches. The bigger the target, the farther away it has to be from the coil for the detector to pick it up. Depending on the size of the target, you could walk right over a handful of silver coins, a pair of silver dollars or a jar of silver coins and never even know it.



Edited 17 time(s). Last edit at 03/10/2020 12:43PM by Badger in NH.

I think you will find that several detectors will flunk that test.----Good info to know if you are looking for a cache.

I'm surprised they didn't incorporate an overload signal into the Equinox. Many detectors have it.

I did another test on a one quart jar of copper cents and the detector would not overload or go silent even when I put the coil right on it. It's also interesting that the jar of copper coins IDed in the mid teens. I would think a large mass of copper would read higher not lower.



Edited 5 time(s). Last edit at 03/09/2020 04:10PM by Badger in NH.

open up your iron disc all the way and it will probably report on them as an iron tone.

HH
Mike

Mike Hillis Wrote:
-------------------------------------------------------
> open up your iron disc all the way and it will pro
> bably report on them as an iron tone.
>
> HH
> Mike

Yup, I did that and added the info to the original post. An iron tone isn't very helpful when looking for silver.

Badger........ i thought the little triangle that pops over is an overload sending the machine into reduced power. I get it every now and the in the water or over say a can lid out there. Curious ...... if you buried that same stack even with the dirt what you might get? Could it be similar to loosing a target in the hole?

This is pretty common with metal detectors using a DD coil. Concentric coil is no problem for a stack of silver.

I tried the test again with the F-75 this time and it also ID'ed the coins as iron, but I noticed that the detector will only do that if they are in a stack. If you disturb the stack, you get the correct ID.

The same rule probably applies to a jar of loose silver coins. As long as the coins are not perfectly stacked, you will get a high coin reading.

My first cache was a half-pint milk bottle full of silver coins. It had dimes, quarters and half dollars dating from 1852 to 1920 with a total of about 150 coins. The bottle was over a foot deep. I found it using my CZ20 with 8-inch concentric coil.

I just tested the stack of coins with the CZ20 and it gave all high tones. If the coil got within 2 or 3 inches, it gave the overload signal which sounds a little like a 20th century telephone.

So if you are looking for a cache of rolled coins, a CZ will find it.



Edited 5 time(s). Last edit at 03/09/2020 10:16PM by Badger in NH.

I just tested the Equinox again and this time ran through all the frequencies.

5 kHz picked up the coins and gave all high tones no matter how close the coil got to it. All the other frequencies including Multi saw the coins as iron.

5 kHz should be called "Cache mode".

Thanks go out to Monte for emailing his tips and suggestions.



Edited 6 time(s). Last edit at 03/11/2020 08:38AM by Badger in NH.

Good chance EQX is wrapping into iron range.
Deus will do it too. Using lower freq helps deus as well.

Cheers.

It seems to be a common problem with most detectors. Selectable frequency is a nice option to have.

The Multi-IQ frequency range graph actually shows Large Silver under 5 kHz.

Image here - [www.ja-gps.com.au]



Edited 1 time(s). Last edit at 03/11/2020 08:31AM by Badger in NH.