Another fine investigation & repair, and Mike those are useful photos and description for anyone else who looks this up in future
Thanks Martin.
The
really useful discovery is that
it is possible to adequately align the swingarm without going through the very complex procedure described in the Philips service manual, which requires a special glass disc, special mirror and overhead light grids etc.
Here's how you do it:
Set up your player with the baseplate off to expose the underside of the turntable motor and have the player raised up so that you can access the disc height adjustment screw on the underside of said motor (I stand the player on four baked bean tins, one under each corner). Be sure to keep the player reasonably level.
Try to pick a good factory CD disc which looks nice and flat and load into the player.
Set up an oscilloscope to observe the RF eyepattern.
Set up a DC voltmeter to observe the voltage between the negative of the focus motor and earth.
Slacken the two torx screws that hold the plate/pivot of the swingarm
just enough to be able to move the pivots alignment.
What you need to do is find the position that gives the best RF eyepattern at both the start
and end of the disc. This will also be the position that gives the
minimum voltage variation on your voltmeter between the start and end. The two things are interlinked. Take your time an be patient. You'll find that some discs are flatter than others and it'll be much easier with a flatter disc.