Do CZ-5's ever need a tune-up?

I can't tell for sure, but it seems like my CZ-5 has lost some depth.
It's one of the models from the late 90's or early 2000's I think, with the gold shaft.
When I first got it, (I bought it used), I couldn't believe the GREAT depth it got.
With the 8" coil, I was finding silver dimes at 9-10 inches, and Large cents at a foot.
 In the past month or so though, I've noticed that in air tests, it's not getting the same depth anymore, as it did a year ago.
I recently bought a 10' 1/2 coil for it for some beach hunting, and it doesn't seem to be getting any more depth using that coil either.
I'm just wondering now if it needs a tune-up of some sort.
Anyone ever have this experience with a CZ-5 who could possibly give me some advice?
 Thanks in advance for any replies.

I don't know about the CZ-5, but I have a CZ-6a that I think it has lost some depth too as mine as some age on it just like me.  It might cost more to tune it up, if possible, than it is worth.  What I like about it is it is the land version of the CZ20 and can be used in the water while wading.

The CZ5 is one of the best detectors around.I know several that are older than yours and the people still swear by them.If I were you,I would call Fisher and ask them about a tune up and the approximate cost.The detector is well worth it.

I have owned a CZ5 for about 10 years and it is one great machine...hopefully it will last another 10....still no problems...knock on wood...Have you removed your coil cover and cleaned it out??..Sometimes mineralized soil can get trapped inside the cover..and perhaps that can affect depth..

Anyway..the Fishers from that era offered a lifetime warranty and maybe you can get it looked at no charge..Who knows?  I miss those old Fisher detectors..Those machines were legendary..and now they are gone the way of the DoDo.   Gerard Fisher would roll over in his grave if he could have seen what happened to his company.  Can't cry over spilled milk, I guess.

It doesn't matter if your circuitry is breadboard, PC board, chips, nanocircuitry, or microcircuitry; The metal in the solder connections, solid state parts, windings, posts, and other connections s-l-o-w-ly deteriorate and this causes electrons to flow at a different rate than when new. ANY metal detector will eventually need a tuneup, even a simple PI will. And yes, PI's can be really simple circuits just like many BFO's are. Most detectors last up to about 10 years before they need to be recalibrated or overhauled. Some don't even last that long though, especially the complex ones, the ones that have so many things to go wrong with them. Searchcoils usually go bad first but some older breadboards win the race.

Hope this helps.

LL

 

dc current is not the cleanest of current and in time can have an adverse effect on electronics.  Bill

[Oldest Coin - 1841 Seated Half DimeOldest Relic - Silver plated 1700's Colonial Buckle]

There's something like 30 different adjustments on the analog CZ line, and Fisher can retune them to original factory specs.  Probably well worth getting it checked out if it's not too expensive. 

Twenty-two trimmers on my CZ 6a from what I remember and it was suggested that you had a tune up every five years or so. Just make certain its Fishers engineers that do it. I've seen third party efforts that have made the detector far worse.
My tune up by Fisher upped the depth slightly above what it was new and sharpened up the tone. It was expensive but this might have been down to the CZ6a being rainproof and needing new seals.

  Hey guys, thank you for the replies.
I notice that this section of the forum can be pretty quiet at times, so I wasn't expecting so many replies so fast! Good to know how many helpful people are here!
 I cover the bottom of my coils with marine epoxy, so there's no dirt in there.
And occasionally, I open up the housing, to blow out any dirt or dust that works it's way in there.
I know alot of dirt works it way in from my gloves when I detect.
 The other thing is, I'm very hard on my equipment.
I do alot of deep woods, and foundation hunting, etc. (constantly fighting through a jungle!)
And it probably gets twice the amount of use than the detectors of anyone else I know.
 But it just doesn't seem to be detecting as deep as it used to.
In air tests, the signal used to seem like it got great depth at the outer edge of the coil.
Like the signal was penetrating the ground like a "can" shape.
Now it seems the only place it's getting any depth is in the dead center. (Cone-shaped).
It just doesn't seem as strong as it used to be.
Thanks again for the replies!

If a winding in the searchcoil has dislodged you can check it by taking it loose from the pole mount and shaking it up and down AWAY from ANY other metal objects, including as far away from the circuit box as is reasonably possible.

If the sound changes as you do this it is likely that the windings HAVE come loose from the styrofoam or epoxy mountings/glue inside the searchcoil casing. If the searchcoil pattern has changed - look for a dislodged winding inside the searchcoil housing. The earlier AH Pros and Compasses had this problem all too often. So did a few other detectors back in the 80's and earlier.

LL

  Now it seems the only place it's getting any depth is in the dead center. (Cone-shaped).
It just doesn't seem as strong as it used to be.
Thanks again for the replies!

Found the following in the CZ-5 manual on PG19.  When you mentioned "Cone-shaped", I remembered what the dealer told me when I purchased my 1st CZ... He said the signal is conical and the strongest signal would come from the center of the coil...

HH Robert

That old drawing was written for simplicity for people with no comprehension of how metal detectors work or of how EMF or magnetic fields work.

Emission fields look more like two layered "O" shaped configurations back-to-back with the weaker (-) field on top of the coil and the stronger (+) field under the coil. The "O"'s are (theoretically) open at the top (and bottoms) where the coil windings are.  Additionally only the most inner part of the pattern is producing enough field intensity to cause a voltage spike to occur. What this means is that although the normal radiated field is somewhere in the ballpark of a 4 ft positive and a 4 ft negative (which equals 8 ft) it is also radiating outward nearly 4 feet too. It doesn't look like the drawing at all. It looks somewhat like this, with bulges and a couple of cancer-like sores here and there. The lines of force are closer together nearer to the windings and that's why they find tiny objects best closer to the coil. The total field is somewhere in the 8 ft range though. It'a similar to waves coming off the water surface if you toss a rock into it, closer together near the tossed spot and waves farther apart the farther away from it, including under the surface where it produces a half a sphere due to no water being above the surface  . It works similar to sonar and radar. The field IS NOT "cone-shaped", it's more like two 4' potatoes back-to-back with an 8" coil slab between the two. You can check this by using iron filings over a big piece of cardboard over the edge of a searchcoil.  Oh, and patterns are not often concentric or perfect at all, sometimes they are off-center too, and that's why (especially with some Minelabs) the target is found to the left or right of center.
Have fun.

LL
                                                                                      
                                                                            
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