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Thursday, April 13, 2017

Beogram 8002: Preparing the Restoration

The decision has been made to do the full restoration on this beautiful Beogram 8002. The first step is to open it up for service and prepare the parts for restoration.

These early eighties Bang & Olufsen audio components were designed to open up for servicing similar to an automobile hood. The modular design makes it nice to work on. There are still some tricks to learn in properly opening the units up and some out of the ordinary tools are a big help.

I already removed the dust cover and tonearm compartment lid assembly. I need to check why the alignment is off on that later so by removing it the lids won't accidently flip open and get damaged when the deck is tilted up.

To get the Beogram deck open there are only two screws underneath the left side that have to be removed. However, to open the deck up you must carefully detach the three suspension springs and when the deck lid is tilted up you have to maneuver the platter assembly to the right slightly. The reason for that is there is the deck cannot clear the tonearm assembly unless the platter assembly that holds it is shifted.

Here is the Beogram with the deck lid up (dust cover and tonearm compartment lid assembly already removed).






















As noted in the photo, with the Beogram open I discovered another missing trim piece. There should be a black plastic cover for the exposed wiring board on the tangential arm assembly. I will look for a spare or fashion one out of a sheet of Dura-Lar.

Turntable adjustments and tests can be made with the Beogram opened up in this service position. For restoration work though I fully remove the Beogram assemblies so they can be worked on individually or connected together and tested.

This picture show the Beogram 8002 assemblies removed from the case and operating.




















When I had first examined this Beogram I noticed the horizontal parallelism of the reference arm and tone arm was off. The tops of the two arms should be the same. In the picture below you can see the tone arm is slightly higher. The service manual has a procedure for adjusting that and it requires taking the tangential arm assembly out to get at the underside. That isn't a big deal as I was going to lift out the arm anyway to check the lubrication of the tangential arm drive.






















Besides the service manual mechanical adjustment procedures this restoration will rework the Beogram 8002 main board. The electrolytic capacitors will be replaced and solder joints re-flowed on all of the board connectors. Here is the Beogram 8002 main board opened up.




















































...and inside the metal box with the microcomputer.






















There is also a capacitor Bang & Olufsen engineers mounting in the transformer box. This capacitor is a coupling capacitor for the platter drive motor. It is obviously too big to have fit on the main board or on the platter chassis so it was put in the transformer box.




























That is it for preparing everything for this restoration. It is time to start the work.

1 comment:

  1. Yes sir. It gives me great joy to know that my favorite turntable will live on in my son's home. He is very fortunate to have found such professional people as yourself with an obvious passion for all things B&O
    Thank You,

    Mark Lower 2017

    ReplyDelete

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