Beogram 4000: Replacement of the Incandescent Bulb in the Sensor Arm with an LED

I like to test Beograms that I restore for a while to make sure that everything is stable. And so I played a bunch of records with the Beogram 4000 that I recently brought back to life. Sure enough, the light bulb in the sensor arm failed after a while. This gave me an opportunity to adapt my recently developed design for a LED assembly to replace this light bulb in a Beogram 4002 for the Beogram 4000.

Here is an impression of the redesigned Kapton flex board:

It can be folded to fit into the sensor arm bulb cavity:

The 3D printed wedge glued to the back ensures that the LED sits in the right spot that the light is reflected properly into the light sensor in the arm. Its thin leads thread through the slots in the sensor arm bulb cabinet:

The leads can be soldered onto the same pads as the bulb:

This shows it powered up:

The ultra-warm white CREE LED ensures that the B&O logo lights up properly in a warm red, just as if there were an incandescent bulb under the hood! Like all Beolover parts this one is available to other enthusiasts. Just send me an email or use the contact form to the right if you like to get one for your own Beogram 4000 restoration project. 

Any light source installed in the sensor arm needs to be able to generate the proper signal at the collector of TR14 to trigger the record detection circuit. The Beolover LED replacement passes this test with flying colors:

For the record, two more pictures showing the wiring on the sensor arm PCB in case there are issues (sometimes the leads break off when the bulb housing is pulled out):

This shows this Beogram in action with the LED replacement in place:

The record that is playing is 'Latin for Lovers' by Cal Tjader on the Fantasy (8016) label. It came standard in red vinyl...very awesome! I recently found this lovely latin jazz record in Austin, TX at the "End of an Ear" record store. It is great to see how record stores are making a glorious comeback!