Beogram 4004 (5526): Restoration of the Arm Lowering and Tracking Mechanisms

As usual I started the restoration of the Beogram 4004 (5526) that is currently on my bench with rebuilding the arm lowering and tracking mechanisms. This shows the solenoid and damper section of the turntable:

I removed the damper and the linkages for cleaning and re-lubrication:

After I put everything back together it was time to do the same for the linkage that connects the damper with the tone arm. This shows the backside of the arm assembly:

The sensor arm can be taken out by removing two screws that hold it to the floating chassis of the Beogram:

Once the arm is out, the linkage can be removed:

Care needs to be taken to not loose the small spring that sits under the retaining ring. After cleaning and lubricating the pivot point I replaced the sensor arm assembly and adjusted the the arms to be parallel and orthogonal to the carriage guiding rods.

The next step was to replace the incandescent light bulb that provides the illumination for the tracking sensor with an LED assembly. LEDs last much longer than light bulbs and this increases the long term stability of the restoration. This shows the original bulb housing in place:

I removed it, which exposed the tracking sensor aperture:

This shows the original bulb housing in comparison with my LED replacement assembly:

The LED is in the same spot as the filament of the bulb. Like all Beolover parts this part is available to other B&O enthusiasts. Just send me an email or use the contact form to the right.

I installed the LED assembly:

The final item to address was replacing the cracking-prone plastic carriage pulley with a machined aluminum part. This shows the original pulley in place:

And with the replacement and a new belt:

Beolovely! On to rebuilding the electronics!