Featured Post

Beolover SyncDrive: DC Platter Motor Replacement for Beogram 4002 and 4004 (Type 551x and 552x)

Late Beogram 4002 and the 4004 (Types 551x and 552x), which have DC platter motors instead of the earlier synchronous AC motors usually suff...

Friday, February 8, 2019

Beogram 4004 (5526): Restoration of the PCBs

In my last post about the Beogram 4004 (5526) that I am restoring right now, a bad capacitor turned out to be the reason why the arm would not drop at the LP setdown point. So we decided that the main board should be completely restored to prevent further capacitor issues. When one goes the others are probably not far behind. I replaced all electrolytic capacitors, as well as the RPM trimmers and relay:
This shows the 'RPM section' before
and after:
I always mount the RPM trimmers that the screws peek through the original adjustment openings so one can adjust the trimmer while the platter is turning:
While I had this board out, I also rebuilt the output board:
This shows the output relay section before
and after:
The red switch allows connecting signal and system grounds. A convenient feature in case the Beogram is used with a RCA adapter and there is some hum. Usually connecting the grounds cures that.
This concludes the restoration of the electronics...on to the DC motor, which made some nice loud shrieking noises when I tested it.






No comments:

Post a Comment

Comments and suggestions are welcome!