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HP Forum Archive 14

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HP 27s keyboard problem
Message #1 Posted by Nick Nicholas on 6 Jan 2005, 1:46 a.m.

I recently obtained an used HP 27s from eBay. Unfortunately, I discovered that the number 1 key does not always register. If I tap this key like I do with all the other keys, this particular key registers about 80% of the time. When it fails to register, I need to make a hard press to get the key to register and sometimes I get duplicate registrations of the key when I do this. I find this behavior rather strange. Can anyone explain why this key behaves like this and if there is a possible fix?

Edited: 6 Jan 2005, 1:48 a.m.

      
Re: HP 27s keyboard problem
Message #2 Posted by Jeff O. on 6 Jan 2005, 7:18 a.m.,
in response to message #1 by Nick Nicholas

Such problems seem to be common on aging pioneer keyboards. While difficult, successful repairs of pioneer keyboards have been reported, see this thread for example.

      
Re: HP 27s keyboard problem
Message #3 Posted by Randy on 6 Jan 2005, 5:46 p.m.,
in response to message #1 by Nick Nicholas

It really depends on what is wrong. You might have:

  1. Dirt in the key. Not bad, it should clean up.
  2. Something spilled in the keyboard. Okay, but tougher to clean since you don't know what it is.
  3. A just plain worn out key contact. Ugly. Major surgery, follow the previous link and good luck.

If it is just a dirty key, in the order of effectiveness:

  1. Ultrasonic cleaning of the entire unit which cleans inside the keyboard.
  2. Placing a few drops of isopropyl alcohol between the key and the surround and pressing the key a few times. Works many times for not-so-bad units.

Any cleaning should be done with batteries out and allowed to dry throughly before reinstalling. Leaving batteries in a wet Pioneer will result in keyboard destruction via electrolysis in about 24 hours.

            
Re: HP 27s keyboard problem
Message #4 Posted by Nick Nicholas on 6 Jan 2005, 7:44 p.m.,
in response to message #3 by Randy

Thanks to those who responded to my post.

I don't know whether it was my pressing of that key a few thousand times or the isopropyl alcohol or a combination of both but the key registration seems to have improved.

Incidently, I don't have access to a chemistry lab where ultrasonic cleaners are used. Where do you suggest I can get hold of one to use if I have a need for such equipment?

                  
Re: HP 27s keyboard problem
Message #5 Posted by Randy on 6 Jan 2005, 10:19 p.m.,
in response to message #4 by Nick Nicholas

It's not something you would buy for a one-time cleaning. Units large enough to do the job are $200 and up.


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