Proton CD Display Not Working

I have a Proton AC-300 MkII CD player purchased in 1991 and the 7 segment green LED display is not illuminating.

Similarly the Time, Track, Pause & Repeat single LEDs are not lighting up when the appropriate button is pressed. Otherwise the CD and remote control sensor (which is also on the display board) are functioning perfectly.

The LEDs are all controlled by two CD4052B differential 4-Channel multiplexers and the 5 volt power rail seems to be OK to these ICs. Does anyone have a schematic or block diagram of a Proton or similar CD player with a 7 segment LED display which I can use to fault find.

I would have thought a 7 segment display should be pretty easy to trouble shoot once you understand the how they are controlled logically.

Thanks for your help
 
I have a Proton AC-300 MkII CD player purchased in 1991 and the 7 segment green LED display is not illuminating.

Similarly the Time, Track, Pause & Repeat single LEDs are not lighting up when the appropriate button is pressed. Otherwise the CD and remote control sensor (which is also on the display board) are functioning perfectly.

The LEDs are all controlled by two CD4052B differential 4-Channel multiplexers and the 5 volt power rail seems to be OK to these ICs. Does anyone have a schematic or block diagram of a Proton or similar CD player with a 7 segment LED display which I can use to fault find.

I would have thought a 7 segment display should be pretty easy to trouble shoot once you understand the how they are controlled logically.

Thanks for your help
Man! I'm exactly in your same position... trying to give life to this gem. Did you manage to fix it?
 
Hi! Seems like it is Proton, right? Any chance? I mean, I know how to weld and so on, but don't think I have the time to decode a Proton proprietary system for displays 😀

Frontal_Displa_ProtonAC300MKII.jpg
 
Wishing you all the best....but that is a 30+ year old device. Some high end players (Sony) had lasers that were expected to last that long and mine has, and it's quality display too..but all the Phillips players I've had lost their displays.
 
I have only had 5...CD650, and earlier. the earlier ones had 'digit displays' and failed miserably. The 650 display would occasionally blank until re-powered.
Your 25-30 is possibly a better sample but....why did you have so many !!?? lol
cheers,
bob