marantz CD 94 mk2 servo board

If you go to the Philips Marantz web site and look at this image, you'll see what seems to a "bodge" or "afterboard" -- that green PCB, which according to the service manual is a servo board.
https://www.dutchaudioclassics.nl/i...kII-sale/groot/marantz-cd94-mkII-sale-029.jpg

QUESTION; why is this servo board so complex? What in the CDM transport needs so much heavy duty processing?

You can download the full SM at hifiengine.