Fisher CZ 20-21

Ive read that these detectors have problems picking up small gold items and fine gold chains is there any truth to this ? How do these machines compare to the Whites Duel Field ? One detector being being a PI machine and the CZs being duel frequency perhaps they can not be compared? Im talking depth, separation and recovery time. Im referring to salt water hunting



Edited 3 time(s). Last edit at 06/08/2014 03:59PM by Bill1234.

The CZ-21 is locked in salt mode, meaning it will not pick up small gold in fresh water. Even in salt water I doubt it would touch a fine chain.


Aaron

Aaron what does locking in salt water mode have to do with picking up small gold? My question was directed toward salt water hunting, sorry

I don't know if I'm correct on this or not, but I think putting the CZ's in salt mode lowers the ground balance much lower than normal to cancel out the conductivity of salt water, and thus so low (groundbalance) that the detector is limited to the physical size of gold it can detect. I came to this conclusion after reading a lot of Tom's posts on it and noticed it in real time while detecting the salt water beach with my AT Pro. I have to GB way down in the low teens to eliminate the conductivity of the salt water with the Pro, and air testing small gold with it, it becomes obvious that as you lower the GB the gold becomes more and more undetectable. If I find myself using the AT Pro at the beach, I will use auto GB and then manually raise it till it almost becomes unsteady. The CZ's, being multi-frequency, probably overcomes some of these problems, but it's still there to some degree.

I'm sure Tom or others can straighten this out if I'm wrong and give a better explanation.



Edited 1 time(s). Last edit at 06/08/2014 04:40PM by connortn.

cz 20/21 in ANY water (fresh or salt) won't pick up on fine gold chains or other small/tiny gold items due to being locked in salt mode (locked into a lower GB so salt water/wet salt beach sand) doesn't interfere with the operation of the machine.

A "Dual field" won't pick up a small gold chain or tiny gold either

test it all for yourself

put a small gold chain directly ON the coil of any cz 20/21 and/or a dual field machine and you'll see that they won't make a peep

you can put thin gold crosses or tiny rings/ear rings directly on the coils of those machines and not get a peep either

Ex-Cals (all ex-cals) are the same way -- they too can not see/pick up on the tiny/thin gold.

High/er freq. machines not locked in salt mode are how you find tiny/thin gold

that or a GPX 5000!

Steve H is the one you should be asking about this -- he's the resident Guru on PI's, salt water, black sand, etc. hunting and knows all about which machines work best/worst for that type of environment.

HH and good luck



Edited 1 time(s). Last edit at 06/08/2014 11:09PM by MichiganRelicHunter.

Aaron Wrote:
-------------------------------------------------------
> The CZ-21 is locked in salt mode, meaning it will
> not pick up small gold in fresh water. Even in
> salt water I doubt it would touch a fine chain.
>
>
> Aaron


I don't think you would put any CZ in salt mode while detecting in fresh water. If it's fresh water, you should be able to pick up some smaller gold, just as you would in soil. It's the salt that causes the problem.

CZ-20/21 are locked in 'salt mode'. . . . which is about a 45-Deg phase-shift angle induced....... so as to compensate for this 'wet salt' phase-shift requirement. Because of this........ these detectors are gold dead....... even in fresh water.

There is no detector today on the open market that will detect small, tiny or micro-gold in the wet salt environment. This is a market opportunity that is just waiting to happen (be discovered).

In fresh water the Tiger Shark will do a lot better on small non-fe targets than the Excalibur and CZ-21

Aaron

All multifrequency detectors use a subtraction method to notch out salt, which is roughly 90° from ferrite.This happens to be the same as small foil, thin gold jewelry, and tiny nuggets. There is no getting around the physics that notching out salt also notches out small gold, just like the physics of discriminating pull tabs also discriminates some gold.

I guess due to the laws of electromagnetic conductivity ( no clue if that is an actual industry standard term !! ), until there is a detector that can distinguish between the COMPOSITION of salt water vs small gold, as opposed to the conductivity of salt water vs gold ( which can be the exact same, thus if salt water is discriminated out, so will all the small gold in that same conductivity span be discriminated out), detectors will continue to be bound by that law.

I think it is very hard to find small gold chains without a pendant attached and thin/small gold jewelry in the salt water and wet salt sand no matter what detector is used.

Ive found the CZ will hit gold much like the Xcal.... about .3 grams. Obviously you might pick up a chain with a clasp having a SS spring or charm bigger weight wise. Like Tom once said.... we are all really just ring hunting out there for the most part.

Dew