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HP Forum Archive 08

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HP28S dead: see picture
Message #1 Posted by Thierry on 30 June 2002, 1:08 p.m.

Hi everybody,

I already posted this request on comp.sys.hp48, but I'd like to get an answer to my problem.

When I turn the power one, the screen becomes black on one side (see picture: http://www.pbase.com/image/2784768/medium)

I tried memory reset function (ON+INS+Right Arrow), and the machines does two beeps, then turns off.

Is this machine dead or is there still some hope ?

Thierry

      
Re: HP28S dead: see picture
Message #2 Posted by Vieira, Luiz C. (Brazil) on 1 July 2002, 12:27 a.m.,
in response to message #1 by Thierry

Hi;

I have seen one HP27 with this same behavior. After being opened, a severe leakage from the batteries was observed.

A cleaning procedure and ready to run!

Take a care look inside the batteries compartment. The turning-off after MEMORY CLEAR procedure is my major concern for now. If there is a battery leakage, the machine's case must be opened (there is an article about it at the Articles Forum). If the display drivers are damaged for any reason, nothing can be done. They are part of the PCB itself.

Success.

            
HP28S: I saw the picture, and...
Message #3 Posted by Vieira, Luiz C. (Brazil) on 1 July 2002, 7:36 a.m.,
in response to message #2 by Vieira, Luiz C. (Brazil)

...I am curious about it. There is a shadow and some light spots in the right side of the LCD. What happened? Maybe it can help defining a solution.

Success.

                  
Re: HP28S: I saw the picture, and...
Message #4 Posted by Thierry on 1 July 2002, 2:45 p.m.,
in response to message #3 by Vieira, Luiz C. (Brazil)

Thanks for the hint. Battery leak is indead a possibility. I think that it happened, as the battery cover is oxydized.

About the shadow you see, I think it's just the reflection of my digicam.

I'll look for how to clean my HP28S in the archives

Thanks,

Thierry

                        
Don't find how to clean it !
Message #5 Posted by Thierry on 1 July 2002, 3:41 p.m.,
in response to message #4 by Thierry

Hi,

I have not found how to clean it. Is there any spray for electrical contacts that I could use ?

If I need to open my 28S, I think that I'll give up. It's crazy; I need to saw it I've seen.

So, any help on how to clean the contacts from the outside ?

                              
Replacement is not that difficult...
Message #6 Posted by thibaut.be on 3 July 2002, 12:19 p.m.,
in response to message #5 by Thierry

... There are plenty of 28S for sale on ebay, and price is quite affordable. $/ 60 is a good estimate.

You're right, opening them is possible but is quite difficul, and leaves some unrecoverable marks...


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