cz-6 not powering up

[tipper]

Hello all-

I tried a search, but I came up empty. My boss loaned me his cz-6 that has been sitting unused in his barn for several years. Upon receiving it, I installed new batteries, but the unit does not appear to power on. there are no beeps and when I do the battery test, it reacts as if there is no battery installed--it does nothing. I checked the batteries, and although they read somewhat low for a new battery (I live in a small town and the only place to buy the batteries was at the dollar general--and they don't tend to have the best/freshest batteries), they should have done something. I had some other 9V around, tested them, and tried them. They measured almost 10V but still nothing. I have already tried flipping the batteries every which way in the hopes that I had them in wrong, and as I expected, nothing. It does not appear as if there has ever been any leaking or corroded batteries in the unit. Anyone run into this before? Have any ideas as to what might be the cause or what might need to be checked?

 

[Dan-Pa.]

Do remember CZ6 was made in 92-93 and sitting for years surely an electronic part could have gone bad. Personally I would take a pencil and with the eraser clean the contacts which are recessed in the back of the battery compartment. Even with poor batteries one should get a startup. Perhaps time for a trip for repair but with its age might be cost prohibitive to repair. CZ6 was known to have the coil to box connector fail but the unit would still power up. Might be worth a call to Fisher to talk to a tech for his ideas..

 

[tipper]

Thanks for the input. The eraser trick didn't do it. The possibility of a failed component is realized. I was hoping there would be something (else) simple or common to check. I might just hand it back to the boss man...

If he decides not to have it fixed himself, I may see about acquiring it.

 

[prodrigsr]

Might work. May be contacts not contacting.

 

[Everett Cavanah]

If the input diode saw reverse voltage it may have blown.

 

[tipper]

I wondered about something like that happening too. The batteries I pulled out of it were installed correctly, and the batteries I installed were installed correctly. Before installing the batteries reversed (in the hopes that I had been doing it wrong all along), I checked the manual, and it says, "If either or both batteries are installed incorrectly, the CZ-6 will simply not turn on. The instrument will not be damaged." Actually, up until I saw that, it did not occur to me that I had the batteries installed incorrectly as I'm fairly proficient with battery installation. It was that line in the manual that encouraged the polarity swapping.

After trying the extra rubber in the case to push the batteries that much more (with no positive results), I did throw an ohm meter on the terminals going into the unit, and I get a repeatable ohm reading change from an open circuit to some resistance (which escapes me at the moment) showing that the on/off/volume pot/switch is actually doing some switching. My primitive tests ended there.

 

[tipper]

I forgot to include this in my last post...

Thanks for everyone's help so far. I really appreciate your time thinking on this.

 

[jmaryt]

is the housing sealed well?..possibility of moisture getting into circuitry and causing a short somewhere in light of the fact it was stored in a barn?..just some random thoughts!..smart money says to send it to fisher and let them open it up!

(h.h!)
j.t.

 

[tipper]

I can't even tell how the housing opens so I'm not sure what seals there are. It does not sound like there is water sloshing around inside it. Beyond that, I don't know. It may have moisture related issues inside.

Unless I stumble upon a magic fix this weekend, I'm going to hand it back to its owner with my findings. I don't know if it was his or his dad's back whenever. He may not know or care if it works at this point. The only reason we started talking about it was because it was brought up to the store in a box of stuff from his dad's place.

Anyway, still open to ideas anyone else may have...

All the best!

 

[Turtleman]

Taking the unit apart is very easy. two scews on either side of the coil connector and the electronics just pop out the other end. From there it is very easy to take the 2 pc boards apart and check for corrosion. don't touch any of the adjusting pots, just check for corrosion, or maybe a broken connection to the batteries. It's an old unit and you can't hurt it.

 

[tipper]

I wondered if removing those screws would get it done. I didn't want to remove screws and then have the connector jiggling around inside the still sealed housing if I was wrong. Unfortunately, my glance inside revealed nothing obvious. There must be a faulty component somewhere on one of the boards as there are no signs of corrosion or disconnected leads.

And that is where we stand.

 

[Dan-Pa.]

Heck its 17 years old and been stored in a barn and extreme heat or cold may have caused damage..If you take apart when you put together make sure the rubbers are not crimped which would alter its weather resistant features should you get working..All in all if it were a newer detector might send back for repair and ask for an estimate but as it stands now paying for the unit as is and paying repair bills may be cost prohibitive..In addendum take it apart and put it in a closet for a week and when you put together it may work as moisture even if you can't see it may be causing the problem..Above all do not spray any additives onto the circuit board as it will do more harm than good...

 

[succ33d]

Sounds like a bad connection has developed somewhere. The actual electrical contact on switch or plug in connection is small, with a little corrosion on there it will never turn on no mater what you do. Electronic connections inside the CZ should be cleaned with care, for example use anti static measures to prevent ESD damage to the electronics on the board. I opened up a CZ 6 many years ago I but don't recall the connections inside that could be the issue.

 

[doindadiggin]

Hi tipper i had the same prob a while back and traced the prob to the metal tape behind the battery terminals it had corroded behind the terminal and i could not see it so i just soldered the wire directly to the terminal worked well, and how long had the batteries been sitting in the unit.terry in oz

 

[tipper]

The boss man shipped it back to Fisher earlier this week. I'll post back what they find wrong with it.

 

[tipper]

It should be on its way back to us as of Friday. They tell us there was a short. Exactly what this means, I do not know. The boss asks me questions when I tell him partial information, but I don't tend to care enough to ask him for more detail when he gives me an answer like "there was a short." Thanks for all the help!

 

[tipper]

Received unit back. It looks as if they also did the standard cz6 --> cz6a upgrades mentioned elsewhere. The invoice shows that they replaced a switch, headphone jack, coil, and coil connector. It now works as it should.

 

[avel]

great comments, and very helpful ones. I own a cz6 and i also like to send it to Fisher to upgraded. Do you happen to know where he send it (the address)? Any help is appreciated.

 

[tipper]

I'll take a look at my UPS book to see where exactly it was sent if no one replies before I get a chance to look. You should be able to find their phone number with relative ease. I'd certainly recommend giving them a call before shipping it off just so everyone is on the same page about what is going to be done. If everything is in working order on yours, I'd imagine they could give you a quote for the upgrade.

 

[avel]

Thanks for your reply. I will look for the address. Happy treasure hunting.