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Beogram Commander Remote Control: Maybe This is the Final Version!..;-)

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Thursday, December 27, 2018

Beogram 4004 Type 5526: Recapping the boards on the second Beogram 4004 from Texas

I removed all of the components that were necessary from the Beogram cabinet to clean out all of the debris from the old transport bushings.



























The cabinet is now ready as I work on the individual components.

I decided to tackle the recapping of the two circuit boards first.
Here is the main (controller) board before the recapping. Note that the RPM relay on this Beogram controller board is the National type of relay. It has a different footprint than the Siemens relay used on the first Beogram 4004 I restored. Beolover's replacement relay assembly comes in both sizes so that isn't a problem. You do need to check that before ordering a replacement relay for your project.






















Here is the output board. It also has the National type relay. So far I have found that whichever type of relay (Siemens or National) is used it will be on both boards.























On the recapping of the controller board I replaced all of the electrolytic capacitors and tantalum capacitors with 105°C, Japanese electrolytic capacitors or WIMA MKS capacitors. The two trimmers for the 33⅓ RPM and 45 RPM platter speed calibration were changed to sealed, multiturn type trimmers. I also changed capacitor 1C10 from the original 0.33uF to 10uF. The reason for that is because the stability testing on the DC platter motor after Beolover's restoration process showed that the 10uF value provides more stable speed results.

Here is the recapped controller board.






















On the output board I also replaced the electrolytic and tantalum capacitors with 105°C Japanese electrolytic capacitors and WIMA MKS capacitors. The muting relay was traded out for the Beolover replacement relay and our usual grounding switch was installed. The grounding switch provides more options for the phono cable connection to non-B&O preamplifiers. In most cases it eliminates the need for the extra, external grounding wire from the Beogram to the preamplifier.
























Both boards are ready to use.

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