No Beomaster 8000 restoration is complete without rebuilding the displays. They will all fail eventually, and most in the near future. And since those beautiful large LED displays are a main design feature of this lovely receiver, nothing is more frustrating than having a few missing segments. No matter how good the condition of the enclosure, when the displays are not complete it just looks sad! Not beolovely at all!
Luckily the displays are large enough that one can update them with 0603 packaged SMD LEDs, which can still soldered fairly well by hand. For this to happen one needs to extract the displays from the display board:
Once liberated, the next step is to open them up and scrape off the original LEDs, which are directly bonded to the PCB...truly a 1980s design!:
Once the pads are prepared it is time to line up the SMD LEDs and solder them into the places of the original LEDs:
The critical element here is to place the SMD LEDs precisely into the areas that are underneath the light guides in the LED assemblies (white parts with long slots in the picture above) when assembled. If they are not centered, the LEDs will get damaged during re-assembling the displays since the light guides will exert lateral pressure on the LED packages, which can result in them breaking off their pads. I do this by soldering the LEDs on only one side, then checking where the LEDs come close to the light guide slot walls, and then I correct the position of those that are a bit off. Once all are properly in place, I solder them on the other side.
After soldering all the LEDs in, it was time to give the boards their first 24 hrs test. For this I have a breadboard setup that mimics the wiring on the display PCB:
Let's see if they are still all on tomorrow!
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