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This is the first Archived Forum which was active between 17th April 2007 and 1st March February 2012

 

Latest post 10-10-2008 7:14 PM by stephend. 4 replies.
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  • 09-14-2008 5:55 PM

    Beogram 1000 speed change

    Hello! My first post on this forum...

    I'm putting my father's Beogram 1000 back into service after a 20-plus year layup. It's a model 5203, with the round motor, 3 speeds and the chrome speed change control. When I first fired it up, it ran fine at 33 and 45, but stopped turning when I selected 78. It stayed not turning when I went back to 33, but gentle clockwise pressure on the control got it going again. It plays fine at 33 (and sounds good: gives my modern Rega a run for its money!), but won't run at all at 45 or 78. The fine adjust is siezed as well.

    As far as I can make out, it's the drive belt tension that pulls the idler wheel against the motor spindle. The arm with the idler wheel moves easily, and the speed change mechanism appears to work fine. However, I noticed that the drive belt seems very slack, and I'm guessing this is the main problem - although I'd have expected this to be worse for 33, since this is the smallest-diameter part of the motor spindle (I think?). Can anyone advise me on this, please? Plan A is to source and fit a new drive belt, cleaning up the rubbery deposits from the motor spindle and pulley before I fit it.

    What I can't figure out at all is the fine speed adjust. I can see the control spindle, and a wire with a tensioning spring joining its two ends together, which runs round a pulley and attaches to a lug on a kind of brass ring that runs around the motor spindle. My guess is that rotating the control spindle causes the brass ring to rotate, but I can't figure out how that alters the speed. In my case, I can't move either the control spindle or the brass ring. Can anyone advise me how to set about freeing this up, please?

    I also noticed that the motor runs quite hot, enough to warm up the shelf that the deck is sitting on. Is this normal? I can hear a very small amount of noise if I put my ear right next to the deck, but I can't tell if it's motor noise or belt/pulley noise. The motor spindle spins very freely with no noise or stickiness, so I think I've escaped the curse of dried-up bearings.

    I'd be grateful for any hints and tips that you folks out there can give me!

     

  • 09-15-2008 3:10 AM In reply to

    • Dillen
    • Top 10 Contributor
    • Joined on 02-14-2007
    • Copenhagen / Denmark
    • Posts 5,008
    • Founder

    Re: Beogram 1000 speed change

    Welcome to Beoworld and thanks for signing up as a silver member, your support is greatly appreciated !

    Your Beogram will need a new belt. You're right in assuming that the belts tension keeps the idler wheel in contact with the motor pulley.

    To confirm this, you can simply cut out 10-15mm of the length of the old belt and glue the ends back together using superglue. Cutting the belt at an angle gives more surface for the glue to stick to.

    The fine speed control works in different ways on different motor types. Yours, I believe, is a mechanical brake using felt pads inside the brass cup and it's excentric motion will brake the motor more or less.

    A bit of acid-free oil (sewing machine oil) to all of the joints down the speed setting spindle will free it up, leave it to soak overnight and repeat the next day if still frozen.

    The motor will run a bit warm, that's normal.

    Martin

  • 09-15-2008 5:18 PM In reply to

    Re: Beogram 1000 speed change

    Martin, thanks for your help, much appreciated.

    Your description of the fine speed control is spot-on. If I lift the motor pulley gently, I can feel the increased friction from the felt pads. I succeeded in unhooking the spring that tensions the drive wire from the control, and verified that the brass cup turns freely throughout its range of travel, but the spindle is siezed, so I'll try to free it up as you suggested.

    You wouldn't by any chance happen to know where I can source a new belt in the uk...?Smile

    Stephen

  • 09-15-2008 6:03 PM In reply to

    • Dillen
    • Top 10 Contributor
    • Joined on 02-14-2007
    • Copenhagen / Denmark
    • Posts 5,008
    • Founder

    Re: Beogram 1000 speed change

    No, but there's a german seller at Ebay occasionally listing some.

    Martin

  • 10-10-2008 7:14 PM In reply to

    Re: Beogram 1000 speed change

    So... I succeeded in freeing up the fine speed adjuster - needed a lot of perseverance, but very satisfying! I cleaned off all the rubbery deposits, re-assembled everything, and fitted a new belt. (Took a while to source a belt, from LP Gear in the States - only just arrived a couple of days ago.) It all works, but...

    When I fired it up, there was quite a lot of motor/belt/whatever noise, and I could feel the chassis vibrating. Tweaking the motor position cured the chassis vibration, and I believe the motor is now correctly centralised so that it's supported on its springs and not fouling on the nylon transport protectors. However, there's still audible noise, and my impression is that it is getting through to the pickup.

    One thing I notice is that the noise changes if I tweak the fine speed adjuster, although not in a systematic way. The fine speed adjuster does function, although it's a bit hit-and-miss because the control wire sometimes tends to slip on the drive spindle.

    I'd be most grateful for any hints on where to start looking for the noise. With the belt removed, the platter spins beautifully freely, so it's not the main bearing, and the motor spindle is similarly free.

    Stephen

     

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