In response to jon glass's message  on Mar/08/2000 07:44:

 >Hi-
 >
 >I could have sworn I kept the url for cleaning Duo keyboards, but now I
 >can't find it. It is gone from my mail. Could somebody be so kind as to
 >forward the url again. I promise not to delete it this time. 
 >
 >-Jon Glass
 >Krakow, Poland
 ><mailto:[EMAIL PROTECTED]>
 ><mailto:[EMAIL PROTECTED]>
 ><mailto:[EMAIL PROTECTED]>
 >
 >
 >
 Don't know the URL but here's the article:
------------------------
How to Clean and Repair your Duo Keyboard

These instructions were not written by me, but they produce excellent results; the 
identity of original author is unknown to me.

TOOLS REQUIRED: 

  A flat dry wooden table of at least 1 sqm 
  Torx T8 Screwdriver 
  One small flat bladed jewelers screwdriver or a pocket-knife 
  A small dry and clean painters brush (not necessarily!) 
  A clean and dry piece of cloth 
  A small bottle of Alcohol (70%) 
  A printout of a screenshot of the keycaps control panel

TIME REQUIRED FOR THE WHOLE JOB

About twenty minutes 

REMOVAL OF THE KEYBOARD 

(Same procedure as the first steps of RAM installation) 

Shut down the Duo, latch the cover and turn it over. 

With the T8 Torx screwdriver remove the three screws in the bottom of the Duo that 
form a symetrical triangle (NOT the one that lies underneath the trackball!). Pull the 
screws out, place them in a glass and put them aside. 

Open the Duo slowly (still upside down). The keyboard will come free but will have two 
ribbon cables still attaching it to the inside of the Duo. Holding the keyboard 
outside its recess, turn the Duo around, open the lid completely, and carefully tilt 
the keyboard towards you, so that it comes to lie -- upside down -- on the palm rest 
of the Duo. 

The keyboard is fastened to the Duo with two connectors which have small tabs on their 
right and left side. These tabs are very delicate and have to be pushed out about 3-5 
millimeters straight back towards the screen hinges with the jewellers screwdriver or 
pocktet knife. After releasing the four tabs, the keyboard cables should come free and 
can be pulled out of the connectors. 

With the tabs pulled out, take out the keyboard and close the Duo and put it aside. 

DISASSEMBLY OF THE KEYBOARD 

The single keycaps can be removed (and the re-placed) very easily without any tool, 
just with your fingers). Remove them in an order and one after the other and place 
them on the table in the order they were arranged on the keyboard. Place them in a 
distance in front of you, so that there is still some working area left for cleaning 
the keyboard circuitry. 

Under the keys you will find an rubber sheet which provides the keys with their 
pressure resistance. Remove this sheet and eventually take the opportunity to brush it 
clean with the paintbrush. Do NOT use alcohol on it, as rubber tends to be susceptible 
to alcohol! Then place it aside. 

Under the rubber-sheet two transparent foils (mylar sheets) imprinted with the 
keyboard circuitry appear. They look like overhead sheets with a funny metallic 
doodle-mosaic. These foils have got extensions which form the flat cables that connect 
the keyboard to the motherboard. These cables are passed through to slits in the 
keyboard base. Be VERY careful when pulling these cables out of the slits, so you 
don�t harm the imprints on them! place them onto the table with those sides up, that 
are touching each other, as they are in position in the keyboard. 

When you succeeded in removing the to foils (You don't have to remember their order 
for reassembly, it is self-evident!), eventually brush the base of the keyboard and 
put it aside. 

CLEANING THE KEYBOARD CIRCUITRY 

The imprinting on the foils forms contacts on their adjacent sides, that are closed, 
when a key is pressed. these contacts are susceptible to dirt and possibly even 
oxidation.Therefore to clean them, moisten the handkerchief well with the alcohol and 
clean the foils on both (but ESPECIALLY the adajacent) sides. As you should exert 
enough force to remove the dirt, rub the foils with gentle force, but be very careful 
int the area surrounding the shift-lock - LED that is glued onto the upper of the two 
sheets! 

Clean each side twice, you don't want to repeat it too soon... 

REASSEMBLY 

When the contacts are cleaned you reinsert the cables into the slits in the keyboard 
base and put the foils into position. MIND that the foil with the LED on it, is the 
upper one. Apart from that, you can�t put them in wrong. Now you replace the rubber 
sheet and reinsert the key caps. If the cat had a play with them in the meantime: it 
should be no problem to turn on the Duo with the keyboard missing, to have a look at 
the keyboard DA just using the trackball...
(But DON'T FORGET to shut it down before re-cabling the keyboard!). Some of the key 
caps have metal guides attached to their bottoms. insert these into their counterparts 
in the keyboard-base during the process of re-pleacement. 

Now you place the Duo in front of you again, unlatch it, place the keyboard on the 
palmrest, so that it can be tilted back into the keyboard-recess nicely (upside down 
and number keys to your belly!). Mae sure that the tabs on the cable-plugs on the 
motherboard are still pulled out. Gently re-insert the cables into their plugs and - 
fastening them there with one finger! - push the tabs in again. Slap the keyboard in 
place. Close and latch the lid. 

Turn the Duo upside down and re-place the three screws. Don't fasten them too tight, 
because that again might lead to
unresponsiveness of the keyboard! 

Replace the battery, and try it out! 

[EMAIL PROTECTED] wrote: 

   1.The instructions suggest that the keys make contact by pressing the mylar sheets 
together. This is not the case. The mylar sheets simply function as a two-level 
printed circuit. Contact is made by pressing carbon-impregnated rings on the underside 
of the rubber sheet against matching pairs of semi-circular contacts on the mylar 
sheets. This implies that the rubber rings have to be cleaned every bit as carefully 
as the  mylar sheets -- more so, even, since at least in my machine they were dirtier. 
I used cleaning compound designed for the pinch roller of a cassette deck. If you use 
this stuff be careful: while it's ok for rubber (designed for it, in fact), it eats 
polystyrene. 
   2.As noted in the instructions, the keyboard ribbon cables are attached to the 
motherboard via two connectors, each of which is secured by tiny little latches on 
each side. The instructions suggest retracting these latches 3-5 mm. They don't move 
that far. About 1.5 mm will suffice. If you exceed 2mm the latches snap out of the 
connector. I managed to get the one that I snapped out back in again, but was happier 
on the other connector to leave it all attached. 

The whole business took me about an hour, but I was slow and careful about it. 
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