No new drive belt as yet, the old one is a very good (ie not loose) fit and when playing is very stable for most of the time, just the occasional wow and then back to speed again. 'Happens roughly every 10 or 15 minutes or so, sometime goes for a whole side without doing it..Motor has nice torque, belt is good and clean. My guess is maybe the relay contacts maybe..The motor noise is only with the belt on, with the belt off it is as silent as a silent thing in silent land, on a silent day..

joeyboygolf:

Have you fitted new drive belts??

I use stroboscopic disc and mains lighting at 50Hz. Rotation is very stable.

My turntable drive motors, both AC and DC are absolutely silent!

Tell us, did you replace or clean the two speed adjustable resistors? A bad contact at the cursor could generate that sort of thing.

Replace or clean those R1 and R2 adjustable resistors. Do you have any skills (like building kits) in electronics?

Also a noisy motor usually is more obvious when turning without its belt... So my guess is an electronic fault but then the deck is at your place!

chartz:

Tell us, did you replace or clean the two speed adjustable resistors? A bad contact at the cursor could generate that sort of thing.

Replace or clean those R1 and R2 adjustable resistors. Do you have any skills (like building kits) in electronics?

Also a noisy motor usually is more obvious when turning without its belt... So my guess is an electronic fault but then the deck is at your place!

Hi Chartz,

I haven't replaced anything as yet, no time for now, but thanks for the advice..always accepted, never rejacted..

Yes I cleaned and checked all the adjustable resistors some time ago, the problem still persists.

And yes I have Electronic skils, 22 Years in the Royal Air Force as an Electronics Engineer on Radar, Boimedical Electronics and the like, so have plenty of experience, Just at the time didn't have recourse to a CCT Diagram (which I now have thanks to this very site), so was just looking for a "short cut" if you get my drift. I also always go for mechanical issues with any electronics as most of the time the issues are usually the mechanical parts thereof. Also from my experience with the 4000 and other such B&O equipment I am aware of the overall good design and general reliebality of their kit.

Now I have the CCT diagram I will 'scope the Motor supply over the weekend to see if all is ok, as an aside I have quite heavy DC on the mains here and had to trim the Motor supply for my 4000 (ac motor) to get it to run quietly.

Will update with scope shots, and general piccies as I progress.

Steve F

Hi all, at last a quiet 4002 and now completely stable all the time. Thanks everyone for their help and advice. I replaced the on board resistors which were a bit flaky and removed the old isolation gunge from the Motor and replaced it with a piece of thin cork. Originally the motor was getting mechanically coupled to the main chassis with the drive belt on and not so with it off, also as there was damage to one of the motor screw threads the motor was slightly loose in its mount. With the thread repaired and the piece of cork stuck to the motor base it is just lovely....'Took me a while as I work long days here and get back quite late in the evening. Playing J.Cash as I type. These really are quite nice pieces of engineering and sound better than the "Hi-Fi" pundits would have you believe.

Very glad to hear it :) Did you place the cork between plastic casing for the motor and chassis or between motor and casing? Might try that myself!