Beogram 4002: Conversion of the Tracking Sensor Light Bulb to an LED and Adjustment of the Sensor

I started working on a Beogram 4002 that I obtained locally from Craigslist about a year ago. I thought it would be a nice practice run before I give the cherished Beogram 6000 4-Channel a go that I recently found.

I plugged it in after opening it up in the hope to see the location of the smoke should any develop...;-). No smoke, but no tracking either. Pretty much nothing worked, no tone arm lowering etc...also some traces of amateur repairs.

I determined that the light bulb in the tracking sensor was out, and I decided to replace it with an LED since the bulb cannot easily be replaced since it is glued into the sensor housing, i.e. cannot be separated. I also am a fan of LEDs since they have a much better long-term stability, especially should the unit be shipped at some point.

I ended up using a 3D printed part to hold the LED and the current limiting resistor. The part essentially replaced the light bulb fixture on the sensor housing. Here is a picture of the end result:

I made a video that explains the whole procedure including the adjustment of the tracking mechanism for the right tone arm angle relative to the record grooves. The video also discusses how the tracking mechanism works. Enjoy!:

On to the dead sensor arm!