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DUAL 506 motor problem

M

mcdonougha

Member
I've been working on a DUAL 506 TT for a couple weeks now and recently mounted and aligned a Ortofon 2M RED cartridge. The problem I seem to be having is that the motor is too slow thus causing records to sound funny. Is there any way to fix this without replacing the motor itself?
 
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mcdonougha said:
the speed adjustment belt is fine....though when i do turn the knob, nothing seems to happen
Click to expand...

Then you know where to look first - remove the platter and observe the adjustment cam while turning the knob. If thats not the problem, then check the drive belt tension and look for anything that might be binding the belt or the platter. Is the drive pulley clean and wobble free? Remove the belt and check it for binding.

Note that the speed belt is notched like an old fan belt - it may seem intact but is actually missing teeth which engage a gear in the adjustment cam.
 
mcdonougha said:
the speed adjustment belt is fine....though when i do turn the knob, nothing seems to happen
Click to expand...

Then your pitch control isn't working. On my Dual 506, the pitch "gear" cracked into three pieces. I had to super glue it back together and it worked fine. Your is either broke or stripped I would suspect.
 
Sweet!:thmbsp:

BTW I loved mine until the cat decided to do a gainer from it. He kicked it off the table with his feet when he jumped. I was pissed but couldn't really blame him, hes just a old stupid cat.
 
There is a conical wedge that slides up and down inside a small metal cylinder -- this assembly slides into the "vario-pulley" from the top. When you adjust the speed, a plate presses up and down on the wedge, causing the wedge to make the sectors of the vario-pulley expand (faster) and contract (slower). The common failure is that the wedge and cylinder get sticky, and the wedge wants to freeze in one position. This has little to do with the "centering" adjustment (the plastic hexnut).

To repair this, the above assembly must be disassembled and cleaned -- sometimes even fine-sanded -- to remove corrosion and sticky grease.

Fred
 
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