My Beogram 4000 restoration continued with replacing the control panel’s light bulbs with LEDs. This enhances the unit’s lifespan and prevents issues that incandescent bulbs, susceptible to vibration, can experience during shipping.

The top two bulbs illuminate the Beogram’s unique position indicator, while the vertical bulbs light the RPM trimmers. I recently designed SMD LED-based PCB replacements for the position indicator bulbs (available via email).

Standard red LEDs with current-limiting resistors can replace the RPM trimmer bulbs. Here’s a photo of the installed LEDs:

And here they are illuminated after powering up the Beogram:

The position indicator LEDs are red-green LEDs calibrated to mimic an incandescent glow, ensuring red photons illuminate the red scale indicator.

This image showcases the LEDs with the panel closed. The red indicator is absent as the panel hasn’t been fully reinstalled yet. I need to address the malfunctioning keypad switches, which are likely corroded and causing issues with the slow scanning functions.

The design is very aesthetically pleasing.

I also took the opportunity to reattach the strobe light mirror, which is often detached in units of this age:

Next up: tackling those keypad switches!