11 Jul
2007
11 Jul
'07
1:22 p.m.
A thorough cleaning is in order before you replace
all that. I bathe my keyboards in a 10-15% solution of
ammonia and water. I haven't yet disassembled a V9K
keyboard, but I imagine it's typical as far as
keyboards go. Remove the plastic and toss it in. If
you need more details, I'll provide. It works well.
The notes I made when I repaired my Sirius don't say how the keyboard is
made, but from the schemaitcs, I'll bet it's a Keytronics. There are the
sadnard pair of Keytronics ASICs linked to a microcontroller (in this
case an 8021).
The outer casing will come off easily, screws on the bottom I think. Then
take out all the tiny screws ont he bottom of the PCB and seprate it from
the keyframe.
Personally, I take the whole lot apart and clean the bits separately. It
takes longer, but if you get liquid into the foam pads of a Keytroncis,
it'll squish for a long time....
There are 2 common failure modes of the Keytronics 'swtich'. The foam pad
between the 2 mylar disks breaks up, or the metalisation on the lower
mylar disk vanishes. Eary to repair if you can find some spaee assemblies.
-tony