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Gemini Battery

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#1 BRCoz

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Posted 22 March 2009 - 01:32 AM

I got a new Gemini in January, and out of the box it needed the CMOS battery replaced. After getting a new battery, it needs to be replaced again. It did not last two months. Due to work and weather I have not even had it out with a scope. It uses the CR2354 and I can’t just drive down the street to get one. I sent Scott an e-mail to see what he says. I know this can be fixed. Anyone else have this happen? I have read where an external battery using two AA batteries mod could be done. I really don’t want to do that.

Bruce

#2 skybsd

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Posted 22 March 2009 - 07:35 AM

Hi Bruce,
Good to hear from you..,

Tough break there - it always sucks when new toys don't appear to work as expected..,

What you're describing sounds bizarre - A new battery should last (depending on local conditions) between 11 - 13 months.

What is it that you're experiencing that suggests that the replacement battery needs swapping out?

Unexpected or zero Gemini responses?
Alarm noises?
Warning messages?

Not meaning to patronise, but subject to your description of the problem, are you sure that the replacement battery is fitted correctly? There are two small metal tabs on one side of the battery holder that needs to make good, positive contact with the top of the battery when inserting a new battery.

Also, the battery IS facing the right way up, yeah? ;)

How are you powering the mount?

Regards,

skybsd

#3 Strgazr27

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Posted 22 March 2009 - 07:42 AM

Unless your getting the message "CMOS RESET" on power up don't be so sure it's the battery. My G-11 uses the older 2032 but I can get your 2354 at my local Rite-Aid. If you need one I would gladly pick it up a mail it to you. They can eacily be bought online for next to nothing.

Sky is right, you also need to make sure the battery is inserted correctly. TRUST ME.....I speak from experience :(

These batteries should easily last as long as Sky says if not longer. The battery in my CGE was 4 yrs old before I replaced it.

#4 David Pavlich

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Posted 22 March 2009 - 11:16 AM

Bobby's right. The battery lifespan should be measured in years, not months. If you're doing it correctly, then there is some sort of shouldn't-be-there drain. It takes just a tiny amount of juice to keep things alive in there.

David

#5 HunterofPhotons

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Posted 22 March 2009 - 11:50 AM

The reason that the battery was changed to the CR2354 from the earlier battery is that its life span is good for several years.
I've been hanging around Gemini groups for years and never heard of one going bad after two months. As the others have pointed out, are you sure you're installing it correctly?
You might want to ask this question of Tom Hilton on the Yahoo Gemini group. He's quite knowledgeable about Gemini electronics.

dan

#6 BRCoz

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Posted 22 March 2009 - 12:50 PM

The battery is in correct. The tab is marked + and on the bottom of the socket it reads neg. When I first took the battery out it read .067v. After an hour or so I checked it again and it read 3.0v. I took a new CR2032 and put it in. Within 10 seconds it dropped to 2.7v. Now that the CR2354 was at 3v I put it in sideways so I could check the voltage, it immediately went to 1.6v. I found sites on the web that list the battery however, they are not in stock. I placed another order and will see how long they last. For the battery I bought the expiration date was 2015. The socket the battery goes into only has one large tab not two like the one for the CR2032 batteries. I did get the CMOS reset message after the two months. I am using two 12v 7amp hour batteries to power the mount. I have four of them that I would use in the field. I went out to both Losmandy & Gemini yahoo groups last night however, they seemed to be having network/connection issues when trying to get into messages or files. I’ll try again today.

Bruce

#7 blueman

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Posted 22 March 2009 - 01:02 PM

Hi Bruce,
One possibility is the shelf life problem of batteries. You will find that batteries that do not sell quickly can sit on a shelf for a long time before they are sold. These batteries do go stale after a while and most batteries have a date for this on the package, like food. If not, then you are assuming an expiration date.
Try buying from a place that sell a lot of batteries if you can not find them locally and if you buy locally, check the date.
Blueman

#8 BRCoz

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Posted 22 March 2009 - 01:21 PM

The date on the package was 2015 so I thought it was okay. I have ordered more and will hope for better results. I looked for a battery at three drug stores, Wal Mart and Radio Shack. I even tried a couple camera shops. The internet was the only place I could find
them.

#9 blueman

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Posted 22 March 2009 - 10:01 PM

Make sure that the two tabs are not bent that hold the battery and possibly shorting the front to the back of the battery.
Blueman

#10 BRCoz

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Posted 22 March 2009 - 11:58 PM

Mine has one long tab about 1/4 inch wide that makes it hard to get the battery out. I was able to get to the yahoo groups today. I read that the cover could be making contact to the + tab and shorting the battery. When I did som testing with a meter the cover was not an issue. The voltage drop was fast. I'll see what Scott recomends.
I want to thank all of you that offered things to look for and try in getting this fixed.

Bruce

#11 Charlie Hein

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Posted 23 March 2009 - 06:00 AM

Sounds like it could be a bad component in the controller. Hope you get it sorted out quickly!

#12 Jeff B

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Posted 23 March 2009 - 07:23 AM

To All:

My Gemini did not wake up last night. Power switch on and...nothing, no red, light alarms beeps..nothing. Took the plate off and fiddled with the switch...nothing. Tried different battery packs...nothing. Power was available from from the 12V output as the GPS do-dad worked fine.

If the internal battery goes south completely, is this one of the symptoms? Any suggestions?

Jeff

#13 Strgazr27

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Posted 23 March 2009 - 10:04 AM

Jeff,

If you open up the front cover on the control panel in I think it's the upper left corner you will see a small fuse. Make sure the fuse is good. Don't trust a visual check either (I have had a fuse look fine but be bad), remove it and check continuity acrossed it if possible. If it is blown that is most likely your issue to start with. You'll than want to find out why it blew.

#14 Jeff B

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Posted 23 March 2009 - 12:30 PM

Bobby:

Many thanks! I was looking for fuses but I obviously missed it.

I'm a Gemini newbie. What's the prefered setting of the slip clutches...not to divert the thread or anything.

Jeff

#15 Strgazr27

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Posted 23 March 2009 - 12:35 PM

Jeff,

Hope that solves it. As far as the clutch settings go that depends on your use and payload. As an imager I have mine set pretty tight. The mount needs a good push to get them to slip. If your doing mostly visual and/or light load you could likely get away with a slightly looser setting.

#16 BRCoz

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Posted 23 March 2009 - 08:15 PM

That fuse is real small. I read that one resets itself and the other does not.

As for my issue Scott said to send in the box and it will be replaced. Here is another vendor that takes care of his customers.

Bruce

#17 Jeff B

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Posted 24 March 2009 - 07:15 AM

Thanks Bobby:

I looked again and the only fuse that I readily saw on my unit was in the lower right hand corner of the board, right next to the power out port. It's very small (~3/16" long and rectangular) and labeled F1. That fuse checked out fine continuity wise. I didn't think to do a resistance check. I also replaced the internal battery. Still dead. :(

I'll have to give Scott a call unless anyone has any other ideas.

Jeff






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