By popular request (really, I got quite a few emails about this!...;-), I finally completed my Beogram DC motor restoration video! It demon...
Saturday, May 12, 2018
Beogram 4004 (5526): Restoration of the Electronics
After rebuilding the arm lowering and tracking systems of the Beogram 4004 (5526) that I am restoring right now it was time to look into the PCBs and the reservoir capacitor. This shows the main PCB in its original condition:
This is a detail shot of the platter motor control circuit:
I replaced all electrolytic capacitors, the RPM relay and the RPM trimmers:
The replacement RPM relay assembly is available to other B&O enthusiasts. Just send me an email or use the contact form on the right. Once this was done, I moved on to the reservoir capacitor:
This Beogram was fitted with a single capacitance reservoir, which I replaced with a modern 4700uF capacitor outfitted with a 3D printed adapter that allowed bolting it into place using the original mounting strap:
The next step was the restoration of the output PCB. This shows the original board:
I replaced the electrolytic capacitors and the output relay:
And this concluded the restoration of the PCBs.