This is usually, but not always, caused by a defective stylus.

Yes, or a broken cantilever...

it's not a broken stylus. can I somehow adjust the force the arm is pulled towards te centre?

THX <mafanni

It is not pulled to the centre with any force at all.  The tip of the arm is tracking the LP track and this force the front of the arm to bend to the middle.  After some time the arm is no longer at 90 degree angle from the base and this is detected by a photo detector which activates a motor until it becomes 90 degree again.

Bad tracking force or bad stylus.  I don't remember anymore how a bad photo detector will show up, does it show up as arm not moving or arm always moving?  Maybe Dillen will know, although I guess the 5500 is too modern for his taste... ;)

A bad photodetector shows up, in my experiernce, by the arm not moving at all once it is lowered onto the record.

Make sure that the tracking force is set to 1.2g.

I still think that the OP's problem is a bad stylus/cartridge, the only remedy is to "bite the bullit" and replace or refurbish it.

Hi,

thanks a lot all of you. The photocell was the problem. It was still working, but the adjustment of the arm was not OK, the sensor did detect.

Unfortenuately that is only one problem, the next I adressed in a new post.

Mafanni