klamsoss
Be willing to fail and try again.
Hello all you CD player experts (especially @dr*audio , you seem to really know your stuff!)
I have an RCD-855 on my bench right now that belongs to a fellow AKer who has done me a solid. I am hoping to return the karma by troubleshooting his CD player. I have narrowed down the issue, but much of the available service manual is impossible to read and CD players aren't really my thing, so I'm not sure what to do next...
So here are the symptoms and the things I have identified so far:
The CD player powers on, and the disc spinner works properly. However, the display and control buttons don't seem to work, BUT, they DO work if you give the player a bump while holding the button down. That includes ALL functions... play, skip, open/close, etc. Once it starts playing a CD, it will continue to play, and it sounds just fine.
Basically, hold the open/close down, lift a corner of the player about 3/4 of an inch up, and drop it, the tray opens. Push the tray closed and it closes properly. Hold the play button down and do the same slight lift and drop thing and the player starts playing. Same drill for stop, skip, etc.
I pulled it apart and checked the fuse. It's fine. (I pretty much figured it would be)
Replaced the power supply cap on the display/control board (found that the old one was just fine after I pulled it, but went ahead and put a new one in place).
Checked B+ on the display/control board and it's correct. (the display/control schematic is the only truly legible portion of the schematic.)
Then I just started checking DC voltages for the display/control board. Everything I checked was close enough to spec that it seems like that is all working fine.
So at that point I'm thinking okay, the display/control board is working fine it's just that the info coming from there isn't getting to where it's supposed to go.
In pursuit of THAT end, I lifted the main board and looked for any evidence of cold solders. I didn't find any but I went ahead and reflowed the solder connections where the ribbon cords from the display/control board attach to the main circuit board. That didn't resolve the issue.
I can't follow the schematic for the main board well enough to understand what's going on with the control signal after it hits the main board. It also doesn't appear to have any spec voltages marked (or, if they are, it's not possible to read them).
I don't have much history on the unit other than that it worked perfectly before it was packed up (very carefully, to avoid damage) and shipped a couple hundred miles. There was no evidence that it was dropped or otherwise mishandled in transit based on the appearance of the packaging. My thought was that something shook loose in shipping but I've followed that theory as far as I can with the limited understanding of CD players that I have.
It would be a shame to have to put this player out to pasture
Any assistance that anyone can offer is greatly appreciated.
I have an RCD-855 on my bench right now that belongs to a fellow AKer who has done me a solid. I am hoping to return the karma by troubleshooting his CD player. I have narrowed down the issue, but much of the available service manual is impossible to read and CD players aren't really my thing, so I'm not sure what to do next...
So here are the symptoms and the things I have identified so far:
The CD player powers on, and the disc spinner works properly. However, the display and control buttons don't seem to work, BUT, they DO work if you give the player a bump while holding the button down. That includes ALL functions... play, skip, open/close, etc. Once it starts playing a CD, it will continue to play, and it sounds just fine.
Basically, hold the open/close down, lift a corner of the player about 3/4 of an inch up, and drop it, the tray opens. Push the tray closed and it closes properly. Hold the play button down and do the same slight lift and drop thing and the player starts playing. Same drill for stop, skip, etc.
I pulled it apart and checked the fuse. It's fine. (I pretty much figured it would be)
Replaced the power supply cap on the display/control board (found that the old one was just fine after I pulled it, but went ahead and put a new one in place).
Checked B+ on the display/control board and it's correct. (the display/control schematic is the only truly legible portion of the schematic.)
Then I just started checking DC voltages for the display/control board. Everything I checked was close enough to spec that it seems like that is all working fine.
So at that point I'm thinking okay, the display/control board is working fine it's just that the info coming from there isn't getting to where it's supposed to go.
In pursuit of THAT end, I lifted the main board and looked for any evidence of cold solders. I didn't find any but I went ahead and reflowed the solder connections where the ribbon cords from the display/control board attach to the main circuit board. That didn't resolve the issue.
I can't follow the schematic for the main board well enough to understand what's going on with the control signal after it hits the main board. It also doesn't appear to have any spec voltages marked (or, if they are, it's not possible to read them).
I don't have much history on the unit other than that it worked perfectly before it was packed up (very carefully, to avoid damage) and shipped a couple hundred miles. There was no evidence that it was dropped or otherwise mishandled in transit based on the appearance of the packaging. My thought was that something shook loose in shipping but I've followed that theory as far as I can with the limited understanding of CD players that I have.
It would be a shame to have to put this player out to pasture
Any assistance that anyone can offer is greatly appreciated.
