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HP Forum Archive 11

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Flakey 28S
Message #1 Posted by James M. Prange on 25 Mar 2003, 5:19 a.m.

I have a 28S that sometimes pauses either while running or taking keystrokes. Sometimes it's barely noticeable, sometimes a few seconds, sometimes seemingly "indefinitely".

The ON key and ON key combinations always seem to get it going again. Of course ON by itself is ATTN or the equivalent of 0 DOERR, but "ON and +" or "ON and -" adjust the LCD darkness, so they work to get it going.

With the "ON and CursorLeft" repeating self-test, it sometimes pauses, but when I get it going, it always gets to "OK-28S"; never a failure.

With the "ON and NEXT" keyboard test, sometimes the keys stop beeping (not repeatably on any particular key or on either half of the keyboard), and if I keep pressing a few more keys (putting keystrokes into the key buffer) and then do "ON and +" or "ON and -", then it responds with a long (somewhat warbly) beep and I can continue the test and end up with "OK-28S".

No apparent external damage and all of the keys feel ok, none mushy or anything. I've put in tested new batteries and of course cleared the memory, but haven't attempted any disassembly.

This has a Version 2BB ROM (as far as I know, the only version used in the 28S).

Has anyone experienced anything like this or have any ideas on what might be causing this or how to repair it?


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