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HP Forum Archive 11

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82240B Repairs
Message #1 Posted by John K. (US) on 19 Mar 2003, 6:18 a.m.

I've got a 82240B that is acting up. After a few lines of printing, it starts printing garbage characters. It looks a lot like some kind of buffer overflow, but setting the delay to 1.9 (max) on my 42S doesn't seem to make any difference, and the 42S works just fine with an old 82240A.

Has anyone seen this kind of behavior before? Does anyone have any experience fixing these things? TIA!

      
Re: 82240B Repairs
Message #2 Posted by Randy Sloyer on 19 Mar 2003, 7:36 a.m.,
in response to message #1 by John K. (US)

If you are running on batteries, it is time to change them. What you describe is a classic low battery situation were the print head speed slows below 1.9 seconds per line and the printer looses sync with the calculator, as there is no handshaking.

It can also be caused by paper chafe build-up in the printer carriage, slowing things down.

You can open the printer by removing the four rubber feet, you'll find a phillips head screw in each tunnel and two more in the battery holder area. A canned air blaster will do the clean-up. Just watch out for the power indicator LED and print head ribbon cable on re-assembly, they don't always go back into place on their own.

            
Re: 82240B Repairs
Message #3 Posted by David Smith on 19 Mar 2003, 6:02 p.m.,
in response to message #2 by Randy Sloyer

Also you may need to clean and libricate the head carriage lead screw.

                  
Re: 82240B Repairs
Message #4 Posted by John K. (US) on 20 Mar 2003, 3:53 a.m.,
in response to message #3 by David Smith

I take it that those parts are nylon or some such? Any recommendations on a lubricant for them? Thanks!

                        
Re: 82240B Repairs
Message #5 Posted by David Smith on 20 Mar 2003, 11:47 a.m.,
in response to message #4 by John K. (US)

Nope, they are good ole metal. I use a gun lubricant called Break Free CLP. Just a TINY amount is all you need. Otherwise dirt, etc can be trapped. I tent to over lube the cam and wipe the excess off while rotating the drive gear to get everything cleaned.

                              
Re: 82240B Repairs
Message #6 Posted by John K. (US) on 21 Mar 2003, 2:57 a.m.,
in response to message #5 by David Smith

Ah! I just happen to have a bottle of Break Free. I'll give it a try this weekend. Thanks!

            
Re: 82240B Repairs
Message #7 Posted by John K. (US) on 20 Mar 2003, 3:51 a.m.,
in response to message #2 by Randy Sloyer

Since the I'm running the printer with the AC adapter, it's probably not the batteries, but I hadn't thought about the possibility of cruft gumming up the works. I'll give that a try. Thanks!


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