[Vinlyfrontier57]

Hi sonavor, many thanks for the link to the Beomaster 6000/2702 restoration on the Beolover blogspot.  There’s a huge amount of useful info here, which I’ll read carefully.

Phil (Vinylfrontier57)

[Vinlyfrontier57]

Craig, thanks for your recollections on which components you replaced in the PCB2 power supply circuit.

I had noticed from the circuit diagram that 0D2 isn’t actually on the pcb, and could be difficult to get at.  Having done my initial inspection without disassembling the main internals, I now need to start pulling it apart to get the the power supply circuits, starting with the tuner dial cord.  Wish me luck!

Phil (Vinylfrontier57)

[Vinlyfrontier57]

Thanks for your post, Craig (#4161).

I checked the 20V and 21V rails that are generated on PCB2.  They measured 10V and 11.5V respectively, so there is a problem here too.

Can you by any chance remember which components had failed on your unit?  Was it the regulator transistor (2TR8) on the cct diagram?

Thanks,

Phil (Vinylfrontier57)

[Vinlyfrontier57]

So if the correct belt length is 88cm, and mine is 56cm, then it’s seriously under-sized!  This explains a lot.  Time for a new belt.

Thanks again.

[Vinlyfrontier57]

Thanks again Mark-sf.  I just got back from hols and measured my drive belt using the method you suggested.  It is 560mm long.  I think your figure of 88mm must be for a different belt?  But thanks for the link to Beoparts-shop – this is a really useful, as they also sell the drive belt for the carriage servo motor, which I need.

Martin – thanks for the reminder about the carriage screws.  I think these are fully withdrawn but will check again!

 

[Vinlyfrontier57]

Thanks again for your guidance, Mark-sf.  After lots more tweaking, I discovered how the position of the leaf springs can be adjusted just enough to centre the platter – as you pointed out in your first post.  So I’ve got it pretty much sorted now. The platter is central, and the top surface is exactly level with the cover plates  – until I place the drive belt over the motor pulley!  It’s a recently purchased replacement belt, and I suspected right from the start that it might on the short side, as it was a tight-ish fit just around the drive surface of the platter.  Can you recommend a reliable supplier for replacement belts?

[Vinlyfrontier57]

Thanks for your helpful reply Mark-sf.

Yes, the plastic inserts in the transport screw mechanisms had broken into lots of pieces and fallen into the bottom of the chassis.  I’ve picked them all out as far as I can see, and they don’t seem to be interfering with the suspension.  But a complete strip-down is beckoning.

I still can’t figure out why the leaf springs don’t seem strong enough to hold the sub-chassis in suspension.  They’re struggling to bring the platter surface level with the surface of the cover plates…  Also the platter isn’t quite central in the opening in the main cover; the service manual suggests that the leaf springs can be moved side-to side to adjust this, but on my model no adjustment is possible.

Maybe a strip-down will reveal all! (The label inside my unit says it’s a model 5502.)

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