Jittery LA36

[Gordon JC Pearce]

Hi there,
   I've finally got the ribbons for my LA36, unjammed the pins in the 
printhead and it is printing.  It's not quite right yet, though...

The printhead often jitters backwards and forwards, sometimes several 
inches.  When you hit "RETURN" it's obviously lost track of where the 
head is, and slams it into the left-hand stop, where it sits obstinately 
  pressed against the spring.

Cleaning up the photosensor bit on the interrupter wheel seemed to help 
a little.

Gordon.