Curious About Fisher Cz Series Detectors

[GB_Amateur]

From things I've read and heard, there is a small but loyal following for at least some of the CZ series (with single digits, -3, -4, -5, -6, etc.) and even claims that they are still today among the best coin detectors.  I wasn't detecting when this series was available and don't know any more than a few snippets here and there in posts.  They do show up on eBay and from (at least some of) the prices, I surmize they are still in demand.  Would someone post an overview of the series, highs and lows, pluses and minuses, etc.?  I think I've read that Tom Dankowski used to mod one of these models for extra depth.  Also wondering if Dave Johnson had a hand in the design/engineering of this series or if they occurred in the time window when he was working elsewhere.

[Steve Herschbach]

So far only Fisher, Minelab, and White's have dabbled in multifrequency in any real way. Fisher and Minelab both introduced their new multifrequency designs in 1991 and so both can argue the fine details of who was "first".

1991 Fisher CZ-6                         5 & 15 kHz
1991 Minelab Sovereign            BBS
1999 Minelab Explorer S/XS     FBS
2001 White's DFX                        3 kHz or 15 kHz or both at once
2009 White's Spectra Vision      2.5 Khz or 7.5 kHz or 22.5 kHz or all three at once
2012 Minelab CTX 3030             FBS2

The CZ series was developed by Fisher Research with lead engineer Dave Johnson playing a major part. Running at 5 kHz and 15 kHz, the CZ is still one of the better coin detectors ever made and is particularly effective in saltwater environments. The CZ-20/CZ-21 is still considered to be one of the best saltwater models made. The basic CZ design is the same with the exception of the still in production CZ-3D, which tweaked and moved various target responses in an attempt to deliver more and better old coin finds. The CZ series is an old analog design requiring a great deal of hand tuning. This tuning suffered greatly as the "old" Fisher at Los Banos went out of business and took time for the "new" El Paso Fisher to get right. Details here by Dave J.

I had several CZ detectors and my personal favorite was the CZ-5. The CZ series will chase coins with the best detectors made today. The only real complaint you will hear is a tendency to identify some deep nails as non-ferrous coin targets.

The Cz series is quite unique because Fisher rearranged the classic target id scale. Nickels in particular were placed at the high end along with the rest of the coins. The scale is very basic - iron (low tone) aluminum (med tone) and coins (high tone). This simple systems is very effective in practice for coin detecting; just go dig high tones. It was so effective the CZ was nicknamed the "Coin Zapper". A fourth tone was added later to break the zinc penny/indian head penny range out as a separate "old coin" range.

Fisher CZ Approximate Release Dates

CZ-6 Quicksilver 1992  
CZ-6a Quicksilver 1992  
CZ-5 Quicksilver 1993
CZ-20 ( Underwater ) 1995
CZ-7 Quicksilver 1997
CZ-7a 1998
CZ-7a Pro Quicksilver 1999
CZ-70 Pro Quicksilver 2003
CZ-3D 2004
CZ-21 ( Underwater ) 2009

I often toy with getting another CZ but I never end up being happy playing the nostalgia game. It was always my wish that Fisher somehow reproduce the CZ as a compact digital design but so far it has never happened. The closest you get is the single frequency F75 which can be set up to emulate the CZ tones to a large degree. Making a direct translation from analog to digital apparently is not easy without something getting lost in translation.

The Fisher CZ-3D is still in production. Information here. For information on changes made in the CZ-3D see Fisher Intelligence, page 5 - CREATING THE CZ-3D FOR THE REAL WORLD

Fisher CZ-5 and Fisher CZ-3D Control Panels Compared (Click on all following images for larger views):

[rod-pa]

Balance with the 10.5" coil is sub-par.  I never had an 8" for mine, but used the 5 and 10.5.  I made up a sling/chest mount for my control box, but should have put some weight on mine behind the cuff to make it better to swing....my shoulder is a bit damaged by swinging it.  I should have spent more effort making it more ergonomic and kept it...it did rock on the wet sand in NJ, and found me quite a few deep old coins inland as well.

 

[GB_Amateur]

Wow, Steve.  You never cease to amaze with your encyclopedic knowledge.  Thanks for the detailed reply and the links.  Interesting read in those Dave J. posts where he talks about the issues with calibration.

Weird how the numbering started with -6, then dropped to -5, up to -7, all the down to -3D (with some two digit models in between).  Without your timeline dates I never would have figured that out and just assumed the -3D was the first, not last.  Also, the way Fisher's webpage is organized (CZ-3D listed as a deep cache detector), I completely missed the fact that it's still manufactured and marketed.  And I've visited that site way too many times to count.

[Mark Gillespie]

Always enjoy the detailed post on this site.  Very informative and I continue to learn of past machines and just how good they are.

[detectorguy]

I always loved my fisher cz-6. It was a lot deeper than my other machine, but I dug a lot of crown caps that id as high coin.

[Badger-NH]

Does anyone know why First Texas discontinued the CZ line?

For some reason they kept making the CZ21 underwater detector and archaic CZ3D but completely abandoned what could have been a cutting edge line of land/beach/water machines that could still be going strong today.

I bought my CZ20 with 8 inch coil in 1998 with plans to get into water hunting and possibly diving. That idea never took off but I ended up using it on the wet sand for 15 years with great results before getting a Minelab Explorer SE. While the CZ20 performed great on the wet sand, it wasn't designed to be used out of the water. When FT took over, I expected to see a whole new line of CZs for land, beach, and water but it never happened.

The CZ multi-frequency technology is as high performance as anything out there today.

My ultimate CZ beach machine would be very simple. 

No screen. Just multi-tone ID.

No speaker.

Ultralight and well balanced.

Accessories not included.

Affordable.

I would choose that over a Manticore any day.

Why would they waste their time experimenting with the Impulse AQ when they had the CZ technology all along?

 

[Geotech]

The CZ3D is a dead end design and financially uncompetitive. It is all-analog, 2 full-sized stacked boards with thru-hole parts, and has 21 trim pots; basically a production nightmare. Yes, we could surface-mount it but even then it's a really big circuit that still needs a big enclosure. Yes, we could digitize it, get rid of the trim pots, and shrink it substantially but that's called "an all-new design."

The CZ design is best thought of as a single-frequency (5kHz) detector with the ability to cancel salt. The 15kHz component is weak and not all that useful for detecting targets. I once proposed a variable frequency design that works the same way but the user can vary the primary frequency from a low of 2-3kHz up to the gold range, maybe 50kHz. At lower frequencies the user could turn on salt cancel. The idea got no interest.

[jmaryt]

hi carl!
 what about tom dankowski's calibration efforts on the cz-3d? did this make any difference in the "true"
over all performance of the analog circuit?. apparently, this circuit was a "bear" to calibrate, but from what everything I have read, once it was "calibrated properly" it would NOT drift for many years.tom introduced the "changes" to the cz-3d so as to "extend" the life of the unit.i still believe it is a terrific coin sniper, and sooo easy, and a joy to use in the field.perhaps as you mentioned the complicated circuitry has contributed to it's present financial predicament, and the fact that t is NOT a digital design has been it's downfall. apparently it is not cost effective to produce.but it hung on. for along time, because guys know how good it is as a coin detector.

(h.h.!)

j.t.