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I recently replaced the CD door drive belt on my BC9500 and this is now fully working again.
Before doing this job when switching off the unit there was always a protracted motor noise 2-3seconds before the relay clicked. Now this does not happen so something is not right. I can still hear a noise but it sounds wrong. I assume something has not seated properly when closing the beocenter from the service position. Thanks for any advice.
I just checked mine - I can't hear any motor noise at all, and it's about 3 seconds between switching off and the relay clicking.
I am encouraged by your reply. I have had mine around 15 years and it has always made a whirring noise before switch off. I thought it was the CD drive or the door motors 'checking' the doors are closed.
Thanks David
David - I just checked mine and the motors do spin up at power down prior to the rely clicking off. I've had a few of these units and they've all done the same.
That said, if your unit is currently working as it is, I don't think I'd be concerned with it.
Take care
Greg
Beocenter 9500, Beomaster 6500, Beolab Penta MKII, Beolab 5000, Beolab 3000, Beolab 4000 MKI, Beolab 4000 MKII, Beogram 3300, Beogram 3000, 2X Beolink 7000 RDS, 2X MCP 6500
If the motors can be heard spinning, it's because the door belts are slipping.
Martin
Martin - Any idea what the logic is (or why) that instructs the doors to close at power off even if they're already closed? Seems an odd function.
PS - I've been lurking here for years and years and have always read your posts (and others) with much interest. Now that I finally subscribed I plan to participate/ contribute more.
It's because the system doesn't know if the doors are open or closed so to be sure they are closed it spins the motors for a few seconds even if they are already closed. Unlike the Beocenter 9300 where the doors aren't on a specified timer but rather stop when they can't move any further.
GregKo: Martin - Any idea what the logic is (or why) that instructs the doors to close at power off even if they're already closed? Seems an odd function.
The doors in these Beocenters (and many other moving B&O thingies) are implemented in a keep-it-simple-stupid kind of way. There aren't any needless limit switches or position sensors whatsoever. When the CPU wants to close a door, it simply runs the motor long enough that the door will end up closed, no matter where it started.
I had never thought that the noise might be caused by slipping belts. But it does make sense - if nothing moved, you wouldn't be hearing much!
--mika
These door systems are in fact quite clever,and I seem to remember that there was a mod to overcome this problem.
Of course slipping belts will aggravate the problem.
I'll try and find the relative info.
Nick
The motor type was changed,and also it was suggested that a 18 ohm resistor be fitted in series with the motor to reduce the noise.
As mentioned above,the drive is applied for a fixed time regardless of where the door is,but in normal use this is not a problem.Loose belts of course will slow the whole process down.
The BC9300 uses an optical sensor/counter to measure the travel of the door,so doesn't suffer this problem.
Thanks Nick and everyone else for the informative replies. I will continue to enjoy the beautiful 9500.
David