Beogram 4002 Type 5513: Main Board Rework and Start of Speed Test #3

Yesterday I ran over to Mouser and picked up a few parts I needed for this project. As I started to work on the main board of this Beogram I discovered I was out of 5KΩ multi-turn trimmers. I needed them for 1R14 and 1R15 which are the 45 RPM and 33 1/3 RPM speed control trimmers. Normally I would just order the parts and they would come the next day. Since it was Friday I would have to wait until Monday and I didn't want to delay this project.

Here is the Beogram main board before removing it.

The Beogram chassis still has the broken transport lock bushing pieces lying around. When I do the replacement with the new Beolover bushings I will clean up all of the loose debris in the chassis.

Here is the main board component side before the recap.

I will replace the axial electrolytic capacitors and the red tantalum capacitors with new 105° C capacitors. The new capacitors will be either electrolytic or WIMA MKS polyester type capacitors.

First though is the replacement of the 45 RPM and 33 1/3 RPM motor speed trimmers. We always replace these two trimmers (R14 and R15) with multi-turn, encapsulated trimmers because they provide finer control over the speed adjustment. We also replace the RPM relay (1RL1) with a modern encapsulated relay. This replacement relay is a Beolover produced part that is drop in replaceable with the original relay.

This picture shows the old and new parts. Notice there is some deteriorating material under the original relay. That isn't needed for the new relay board as it has built in stand-offs.

After those components were in place I replaced the old electrolytic and tantalum capacitors with new capacitors. I also went ahead and replaced the other three board trimmers with new ones.

Now it is time to re-install the main board and run the 33 1/3 RPM speed test a third time. I readjusted the 33 1/3 and 45 RPM speeds with the new trimmers then started the speed test.