I've pretty much got the SME 3012 dialled in ... revised the earthing, resoldered a connection or two, and replaced the styls (from Jico... whoa, that's a business on the bare bones of it's bum. They recon the stylus is genuine Sure, I'm not so Sure). But anyway it plays a hell of a lot better, there was a lot of distortion towards the end of a record that is now gone.
However -- still getting a faint buzzing hum in just the left channel when the tonearm is towards the centre of the platter and the motor is on. Happens about once a revolution for about half a rev.
Slightly mystifying as it's belt drive, the motor is off the edge of the platter in a corner.
So guessing a little RFI coming off the wiring.
The mains input goes through a 5.8k resistor, and then there's a snubber across the microswitch (10nF it seems). There is also a .33MFD across one of the poles of the motor.
From drawings I see of original tables, the snubber should be right at the switch .. mine's rewired as so (by Alty?):
Before I go start messing with stuff, I guess I can move the cap and see if it fixes things.
Seems to be polarised... so how do I check if it's still in good shape?
Any other thoughts on how to make this bastard quieter?
However -- still getting a faint buzzing hum in just the left channel when the tonearm is towards the centre of the platter and the motor is on. Happens about once a revolution for about half a rev.
Slightly mystifying as it's belt drive, the motor is off the edge of the platter in a corner.
So guessing a little RFI coming off the wiring.
The mains input goes through a 5.8k resistor, and then there's a snubber across the microswitch (10nF it seems). There is also a .33MFD across one of the poles of the motor.
From drawings I see of original tables, the snubber should be right at the switch .. mine's rewired as so (by Alty?):
Before I go start messing with stuff, I guess I can move the cap and see if it fixes things.
Seems to be polarised... so how do I check if it's still in good shape?
Any other thoughts on how to make this bastard quieter?
