Re: Apple ][+ keyboard

[Nels Bruckner <nelsb@comcast.net>]

On Sep 30, 3:15 pm, "Michael J. Mahon" <mjma...@aol.com> wrote:
> Nels Bruckner wrote:
> > I picked up a really nice looking ][+ last weekend from a local
> > computer recycler.  Inside I found very minimal dust and everything
> > looks to be in good shape; however, the keyboard seems to have a
> > couple functional issues.  I was wondering if these might ring a bell
> > for anyone -
>
> > First issue is there are 4 or 5 keys that don't register at all.
> > These are spread around the board and include the repeat key.  Second
> > issue is that about 50% of the keys that do function are very 'bouncy'
> > - press the key once and you get 3-4 characters on the command line.
>
> > I disassembled and inspected everything, and the keyboard appears
> > visually to be in great shape.  All the copper contacts on the blue
> > fiberglass board are corrosion free (though I cleaned them with
> > isopropal just to be sure), all the metal pads beneath the keys are
> > shiney and new looking, and all the keys function mechanically just
> > like new.  Cleaned the pins on the encoder board, though it also
> > appears to be in like-new shape.  I did not remove and reseat the big
> > socketed chip on the encoder board, because that sucker is IN THERE
> > really tight and I was afraid to pry on it too hard.
>
> The micron-thin coating of insulating oxide that disrupts seldom-used
> switches is often invisible.
>
> You can either use the "indirect" method of cleaning the oxide layer
> by pressing the keys hundreds+ times, with or without contact cleaner,
> or you can use the "direct" method--disassemble the keyboard once more
> and use a hard eraser ("pen" eraser is what they used to be called) to
> burnish all the contact traces on the PC board and (harder) all the
> metal pads under the keys.
>
> When finished, wash again with alcohol, dry, and reassemble.
>
> That should get everything working again.
>
> To keep it working, use it regularly.  An unused copper contact is
> a place to grow oxide.  ;-)
>
> -michael
>
> AppleCrate II: An Apple II "blade server"!
> Home page:  http://members.aol.com/MJMahon/
>
> "The wastebasket is our most important design
> tool--and it's seriously underused."- Hide quoted text -
>
> - Show quoted text -

     Thanks Michael.  I'll give that a try.

     --Nels