BeoLab 3500 remote (IR) not working

[B3OHACK3R]

Just a quick note here serving as a reference for people having issues with a BL3500 / LCS9000 not responding to remote IR commands. I think this wasn’t mentioned here before.

You can fix it by replacing the electrolytic capacitors around the IR receiver chip (U 2506 B). Likely you are fine by just replacing the 22 uF / 6.3V connected to pin 3 of that IC but when you are at it maybe replace the larger 22 uF / 10V and the 4.7 uF / 25 V as well.

Certainly that also applies to other products using the same IR circuit.

[Madskp]

Great info. Think i has been mentioned now and then, but with reference to the same IR circiut in other products and that it was the blank/shiny caps. So great with actual reference with values.

Location: Denmark

[B3OHACK3R]

BTW I got the schematic from the old BeoLink Active service manual. The IR eye is using the same circuit and it’s included in there.

Only had matching ceramic caps on hand but that’s working well. Used slightly higher voltage ratings due to the dc bias characteristic.

[B3OHACK3R]

Nice how-to repair guide with pictures by another forum member available from here:
https://forum.beoworld.org/forums/topic/beolab-3500-sometimes-responds-to-remote-control-sometimes-it-doesnt/#post-29738

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