"Jouni T Salmi" wrote in message
news:FaArb.156563$Fm2.138193@attbi_s04...
Hi all,

My old Accuphase DP-70 shows unpleasant signs of aging, namely it has
quite severe tracking problems. They occur also in factory made
original CDs in perfect shape. I tried cleaning the lens and it helped
a little, but the problem still occurs.

My next guess is that it is out of focus or the laser power is
decreased. Does anyone have service manual or experience with Sony
BU-1C mechanics? Under the cover I found only trimmers stating "T.E",
"F.E" and "CV-OFFSET". I have oscilloscope etc. basic measurement
instruments, but not any special test CD if such is needed. Any advice
which adjustment I should try (and how...) is greatly appreciated.

I know the player is old, but I don't want to depart from Accuphase
very easily...

.... this has nothing to do with your problem but is Accuphase still in
business?? Have been using one of their intergrated amps. for decades and
it is still going strong(the damn thing weighs a ton!).