denon DP60L


I have a denon DP60L with a straight tone arm and grado gold cartridge. The arm won't pivot vertically. If I move it manually 1" above the platter it stays there. Same at the platter or tilted to the peak. Any suggestions?

I have it rigged with a Mac 4100 receiver and monitor audio studio 6 bookshelfs. Any suggestions for tube amps and pre-amps to join it with?
128x128cjeharnish
thanks elizabeth,
unfortunately, the lift is all the way down. the arm can be lifted by hand, but stays in whatever position one sets it to. I thought perhaps the screws at the pivot point were too tight (the slotted screw-in-a-screw connection) but cannot seem to adjust those at all.

i have a theory which is don't break anything you can't fix. I'm approaching that point.

Thanks.
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you are a champ! I'll give it a try in the next few days and let you know my results. Thanks so much, I look forward to unloaded the old B&O and stepping into the denon.

Thanks again.

Chris