Beogram 4000: Restoration of the Control Panel - LEDs and Gold Plating of Switch Terminals

After gold plating the carriage position switches, it was time to rebuild the control panel of the Beogram 4000 that I am restoring right now. I usually replace the incandescent light bulbs with LED assemblies, and I gold-plate the switch terminals to ensure trouble-free operation down the road.

This shows the original keypad switch terminals, which were quite oxidized:

I removed the terminals:

And gold coated them after removing the oxidation with a fiber glass pen:

And like with the last Beogram 4000 that I did, I forgot to remove one terminal in my first approach...not funny! Here we go:

and after coating:

Pretty, aren't they?? Then I soldered them back into the PCB:

The next step was to replace the light bulbs with LEDs. This shows them in action:

The position scale illumination bulbs were replaced with my custom designed dual red/green LED assemblies:

These boards are available to other enthusiasts. Just send me an email if you want to upgrade your Beogram 4000!

The bulbs that illuminate the RPM trimmers from the back were replaced with through hole high brightness LEDs that are dimmed with 3.3k resistors:

Using strongly dimmed high brightness LEDs saves more current further reducing the strain on the transformer of the Beogram (which gets pretty warm during play) along with the other LEDs that I implanted.

This is an impression of the LEDs in action:

The red-green LEDs create a very authentic background illumination for the position indicator while the presence of red photons in the LED light ensures that the indicator shows up red like when illuminated with incandescent bulbs.