DEC Keyboards with sticky keys

[Douglas Taylor]

I have a couple of LK401 keyboards and they generate a 'keyboard error - 
4' error on power up test when attached to a VT420.  The problem seems 
to be one or more keys that are 'stuck on'.

When the keyboard is turned upside down and shaken I can get the self 
test to pass.

Is it possible to open the keyboards and repair this type of problem?

I also have LK411 keyboards that have a PS/2 type of connector, is there 
an adapter to let me use these keyboards instead of the LK401s?  Are the 
signals the same, only the connectors being different?

Doug