Following the enhancement of the carriage position switches, the control panel restoration of a Beogram 4000 turntable commenced. The project involved a typical upgrade of incandescent bulbs to LED assemblies and gold plating of switch terminals for enhanced longevity and performance.

The initial stage revealed significantly oxidized keypad switch terminals:

The terminals were carefully removed:

Following oxidation removal using a fiberglass pen, the terminals were gold-coated:

An oversight led to one terminal being missed initially:

This was rectified, and the terminal received its gold coating:

The terminals were then soldered back onto the PCB:

The light bulbs were replaced with LEDs:

Custom-designed dual red/green LED assemblies replaced the position scale illumination bulbs:

These boards are offered to other enthusiasts interested in upgrading their Beogram 4000s.

Through-hole high-brightness LEDs, dimmed with 3.3k resistors, replaced the bulbs illuminating the RPM trimmers from the back:

The use of dimmed high-brightness LEDs reduces the load on the Beogram’s transformer, which tends to get warm during operation.

The following image showcases the LEDs in action:

The red-green LEDs provide an authentic background illumination for the position indicator, while the presence of red photons ensures the indicator displays red as it would with incandescent bulbs.