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HP Forum Archive 06

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82143A printer: voltage of rechargable batteries
Message #1 Posted by Rainer Siess on 23 July 2001, 5:43 p.m.

I got a 82143 printer for the HP41 without battery. I would like to use standard NiCd rechargeable batteries. How much cells of 1.2V do I need? Some experiences?

      
Re: 82143A printer: voltage of rechargable batteries
Message #2 Posted by Tony Duell on 23 July 2001, 6:41 p.m.,
in response to message #1 by Rainer Siess

The original battery pack is 4 NiCd cells in series, so about 4.8V. They are Sub-C cells, if you want to make something that will fit into the battery compartment. I can't remember off-hand which sping contact is +ve, but if you take the printer apart (there are 5 screws on the bottom, 4 under the feet and one in the middle towards the back), then the wiring to the battery contacts is colour-coded in the obvious way.

            
Re: 82143A printer: voltage of rechargable batteries
Message #3 Posted by David Smith on 23 July 2001, 10:29 p.m.,
in response to message #2 by Tony Duell

Actually on the '97 you don't have to take the feet off. All the screws are nestled all snug in their little holes... and I do mean snug. Over the years the plastic will have shrunk a little and the screws will be tight. They let out a little "pop" when you first turn them. Do NOT try to tighten them back as tight as you found them or you will learn about cracked screw posts in the '97 series of machines.

                  
Re: 82143A printer: voltage of rechargable batteries
Message #4 Posted by Rainer on 24 July 2001, 4:09 a.m.,
in response to message #3 by David Smith

Thanks! I measured the polarity with a probe.

                  
Re: 82143A printer: voltage of rechargable batteries
Message #5 Posted by Tony Duell on 24 July 2001, 6:03 p.m.,
in response to message #3 by David Smith

Sure you can take a 97 (or any other topcat) apart without removing the feet. But the original question was about the 82143. Now, I know it takes the same battery pack as the topcats, but I don't think we should assume that the chap who needs a battery for a 82143 also necessarily has a 97. When putting the screws back in to plastic (this applies to just about any product, not just HP, and certainly not just the 97), put them in the holes and then turn them counterclockwise (in the unscrewing direction) until you feel the threads engage. Then screw them in. This will reduce the chances of stripping the threads in the hole.

                        
Re: 82143A printer: voltage of rechargable batteries
Message #6 Posted by David Smith on 25 July 2001, 1:02 p.m.,
in response to message #5 by Tony Duell

Oops, my mistake... I had just taken a battery out of a '143A to work on a '97 and had '97/'143A on the brain (or what's left of it) when I read the message. Same warning applies to the tension on '143A screws though. The plastic case will have shrunk rather tightly around them over the years and they can be hard to get out. Use the right size screwdriver. I've seen a lot of stripped screwheads on the '91 and '143A where somebody used the wrong tool.


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