Hey everyone,

For today's puzzle, I present a beogram 4500.  I took an ebay gamble on this along with some other 4500 components as part of a package.  I carefully told the seller how to pack it.  Take platter out, and pack underneath, tighten shipping screws, remove and pack the cartridge separately, tape the tone arm onto a piece of foam.  He did everything except taping the tone arm to a piece of foam.  When the turntable arrived It looked ok, except that the tone arm was floppy.

I opened it up and looked around.  The thin drive wire that pulls the sled back and forth had detached.  Reattaching that was perhaps the more most frustrating thing I've ever had to do inside a piece of B&O equipment.  It's so hard to keep the little wire loop on the little plastic peg!  I got it reattached though.  So now the sled slides back and forth.  It looks like there are three points where the sled sits on the two rails.  As I slide the sled towards the center though, the one of the 3 feet the slides on the rail starts to lift up a little - the one in the rear towards the inside of the turntable.  It lifts a couple millimeters and can easily be pressed back down.  It did this before I reattached the drive wire, so I don't think that's the issue.

Also, I took the cover off the top of the sled to check out the tone arm wobble.  It looks like it is meant to move around a little though.  Is it?  Or should it stay parallel to the speed indicating arm?

Thanks as always!

Austin 

Ok, well I got past the original issues, but am now at a bigger one.  Engaging the manual tone arm drop/raise returned the arm back to its proper position.  Then I tried spinning the manual arm in/out wheels.  After some resistance at first, the gears clicked into place, and the sled slid properly back and forth on the rails.

Now I'm trying to adjust the arm set-down positions.  When I manual spin the gears to move the arm back and forth between the two positions, are those positions supposed to be the two set-down positions?  And if so, how do I manually move the arm all the way to the center again so I can close the lid?

Thanks again, 

Austin 

Normally, if the Beogram is working but unpowered, you can simply push the carriage in and out gently by hand.

The tonearms needs to be in the near-center position to open and close the Beogram when servicing.

Martin

Hey Martin, the tone arm was able to slide back and forth freely. Then when I followed the instructions to manually move the tone arm back and forth (hold that one white section of the gear in, while turning the main platter frame) the sled engaged, and now it moves back and forth only when you manually turn the gears.  So if the sled is already at one end, and then you press in the white tab and start turning the platter frame, then the sled will move to the other end, and once it gets there the platter frame will just keep spinning freely.  Then when you hold in the white tab again and repeat the process, the sled moves to the other end and once it gets there the platter wheel spins freely again.  Using this method to move the sled towards the center though, the sled stops before it moves over far enough to fit through the deck opening.  I'm pretty sure the two positions it moves back and forth between are the 45rpm and 33rpm set down positions, as the tone arm is within several millimeters of those two positions when it's on either end of its travel.  Since I had to remount the drive wire I expected that though, and adjusted it.

So to summarize, I can use the white tab and platter frame wheel to move the sled back and forth, as the manual says to.  The two positions it moves back and forth between are the 45rpm and 33rpm set down points.  So how can I make it move all the way to the center?

Thanks again,

Austin 

Does the servo motor rotate at any point ?

Martin

Hi Martin.  The motor doesn't turn, but if I turn the motor myself then the sled moves back and forth the full width in each direction.  It looks like I made a mistake about moving the manual gear though - the two positions look like the 45rpm set down point on the inner end, and just all the way to the right when moving the other direction - it doesn't stop at the 33rpm set down point.

Austin 

I made a little video of me turning the gears.  I'll upload it later today.

Thanks again. 

Actually Martin I won't bother with the video since I have this almost worked out.  After more adjustments and tweaking, I was able to play a record.  However, I still need to fix the 33rpm setdown point.  When I first tried it, the needle set down on the vinyl about 2 mm away from the first track.  I opened the turn table again and adjusted the little metal lever (the one with the tiny white screw resting inside it) on top of the gear, as the manual says to for adjusting the 33rpm setdown point.  Since the lever was almost all the way to one end I tried moving it to the other end.  I closed the turntable and tried it again.  Much to my shock, I gasped as I watched the needle set down and miss the vinyl altogether, setting down right onto the deck.  (Did I kill the needle?)  Anyway, so I moved the little lever inside all the way in the other direction, but it still sets down about 2 mm outside of the first track.  I noted the manual said to first adjust the 45rpm set down with the wire tension screw on the sled.  I had already done that.  Do you have any ideas for why I might still be outside the adjustable range of the 33rpm set down point?  I'll try readjusted the 45rpm set down tomorrow, to see if that puts me within range for the 33rpm set down.

Austin 

Hmm..

Normally, the adjustments can move more than far enough to allow for misadjustments at both extremes.

It's hard to diagnose without actually "seeing with my fingers" but clearly something is amiss. Hopefully nothing is bent. I think, I would try the wire adjustment again and maybe set it in a little too far.

The needle will not die from landing its 1.2g on the deck surface unless dragged across it.

Martin

When I get home tonight I'll try the drive wire adjustment.  That one seems to offer a much greater range of adjustment than the little lever on top of the gear.

I was being overly dramatic about the needle.  I realized touching the deck wouldn't kill it, but I didn't know whether it would cause any wear on the tip.