Hi,
I have modded my cd67, cd63ki and currently working on a cd63 mod project using Ray's (and others') suggestions.
Having had similar experiences with cd63 and cd67, I would first check the ribbon connector from transport to pcb is firmly engaged.
It looks like the resistor in question is the one closest on the right of cap142, which is (R142) on cd63.
Don't take my word for it though! I suggest having a look at the schematics for CD67 and those for CD63. The resistor connect to the TCA driver Q106, on cd63 that adjusts the laser focus.
Refer to pics from schematics attached. Hope this helps.
Good luck.
Imgur: The most awesome images on the Internet
Imgur: The most awesome images on the Internet
I have modded my cd67, cd63ki and currently working on a cd63 mod project using Ray's (and others') suggestions.
Having had similar experiences with cd63 and cd67, I would first check the ribbon connector from transport to pcb is firmly engaged.
It looks like the resistor in question is the one closest on the right of cap142, which is (R142) on cd63.
Don't take my word for it though! I suggest having a look at the schematics for CD67 and those for CD63. The resistor connect to the TCA driver Q106, on cd63 that adjusts the laser focus.
Refer to pics from schematics attached. Hope this helps.
Good luck.
Imgur: The most awesome images on the Internet
Imgur: The most awesome images on the Internet
Hi
Big thanks for the info, I will try youtube trick
Cd plays fine for a track or 2 then just jitters in one spot, could be faulty "NEW" laser although old laser did the same
I also replaced cap C813 as mentioned by another member, checked ribbon
I am interested in your experiences with this problem and/or what you achieved if any
Cheers
Rover
Big thanks for the info, I will try youtube trick
Cd plays fine for a track or 2 then just jitters in one spot, could be faulty "NEW" laser although old laser did the same
I also replaced cap C813 as mentioned by another member, checked ribbon
I am interested in your experiences with this problem and/or what you achieved if any
Cheers
Rover
Looking at the schematics it looks like R112 on the 67 is the one between the servo (FO output) and the servo amp chip (Q106) - this is R147 on the 63, not R142. The video doesn't give the value of the resistor he paralleled R112 with, on the 63 R147 is 6.8k, be careful you don't take the value too low or you could damage the servo amp chip.
Personally I wouldn't do this - I think the problem is with the new laser (lots of duff ones about). If you've got access to an osciloscope you can play with the trim pot on the transport pcb to adjust the laser level to give a good eye pattern, that's a much better fix.
Personally I wouldn't do this - I think the problem is with the new laser (lots of duff ones about). If you've got access to an osciloscope you can play with the trim pot on the transport pcb to adjust the laser level to give a good eye pattern, that's a much better fix.
There's more info on the laser on this thread, just search laser adjustment or have a look at these posts:
http://www.diyaudio.com/forums/digi...ntz-cd63-cd67-mods-list-1359.html#post1996383
http://www.diyaudio.com/forums/digi...ntz-cd63-cd67-mods-list-1958.html#post3541609
The second link contains a picture of the trimmer, it's directly under the laser head and you will need to take the transport out to access it (and possibly take the pcb off the transport as well, can't remember...)
Like I said, I wouldn't really play around with R147's value myself, on the 63 that input to Q106 links through other resistors to other pins on the servo and to what looks like a feedback network on Q106 itself. If you really want to try this (entirely your responsibility) I would start at maybe 47k which wont shift the overall value much and go down gradually from there eg 33k, 27k, 22k etc. You never know, it may work, on the other hand it may land you with a dead player... good luck and keep us posted on the outcome!
http://www.diyaudio.com/forums/digi...ntz-cd63-cd67-mods-list-1359.html#post1996383
http://www.diyaudio.com/forums/digi...ntz-cd63-cd67-mods-list-1958.html#post3541609
The second link contains a picture of the trimmer, it's directly under the laser head and you will need to take the transport out to access it (and possibly take the pcb off the transport as well, can't remember...)
Like I said, I wouldn't really play around with R147's value myself, on the 63 that input to Q106 links through other resistors to other pins on the servo and to what looks like a feedback network on Q106 itself. If you really want to try this (entirely your responsibility) I would start at maybe 47k which wont shift the overall value much and go down gradually from there eg 33k, 27k, 22k etc. You never know, it may work, on the other hand it may land you with a dead player... good luck and keep us posted on the outcome!
Dead CD63
Hi Everyone,
I've recently been doing some mods that were designed to acheive 2 things:
1) Isolate the top ground plane from any connection other than a single link at the output RCA's
2) Separate analogue and digital grounds
This went OK and the player worked fine and sounded better until I also decided to separate the analogue and digital ground wires at the tx. I'm using the standard KI tx so basically I kept the two yellow wires at U309 and put the grey and orange analogue wires that had been connected to U309 on a separate connection to the analogue ground - this can be seen on the pcb as the top hole of two un-named holes in line with U235, close to (but not connected to) U305
At this point the player stopped working - no sign of the CD spinning up on power on, so I assumed I'd disturbed the flat cable connector once too often. Out with the board, re-soldered all the pins on this connector and the two motor connector plugs, re-assemble and player still dead.
I then measured some voltages and found they were all over the place - with reference to the analogue ground the nominal +10V to the servo amps was ~ +7V, the -10V was -16.9V! and the +5V feed to all the other chips was +0.84V.
The analogue voltages at +and - 12V were fine. Some head scratching and more measurements later I found that my analogue ground was at +4.25V compared to the digital ground - if I measured the digital voltages with reference to the digital ground they were correct at + and - ~10V and +5V.
I've now re-connected the analogue and digital grounds at the tx, all the voltages measure OK and the CD spins, all display and transport functions are OK in that it does what it should do in response to remote control commands but I've got no sound at all, just some white noise if I turn the volume right up on the amps. I swapped the opamps back to the originals but no joy, exactly the same result, so I don't think I've blown the LM4562's but I don't know what I have killed, aaahhrg!
Two questions for all the gurus out there - Where the hell did that 4.25V difference between analogue and digital grounds come from? And what measurements do I need to make to determine why I have no sound output?
Thanks in advance
Hi Everyone,
I've recently been doing some mods that were designed to acheive 2 things:
1) Isolate the top ground plane from any connection other than a single link at the output RCA's
2) Separate analogue and digital grounds
This went OK and the player worked fine and sounded better until I also decided to separate the analogue and digital ground wires at the tx. I'm using the standard KI tx so basically I kept the two yellow wires at U309 and put the grey and orange analogue wires that had been connected to U309 on a separate connection to the analogue ground - this can be seen on the pcb as the top hole of two un-named holes in line with U235, close to (but not connected to) U305
At this point the player stopped working - no sign of the CD spinning up on power on, so I assumed I'd disturbed the flat cable connector once too often. Out with the board, re-soldered all the pins on this connector and the two motor connector plugs, re-assemble and player still dead.
I then measured some voltages and found they were all over the place - with reference to the analogue ground the nominal +10V to the servo amps was ~ +7V, the -10V was -16.9V! and the +5V feed to all the other chips was +0.84V.
The analogue voltages at +and - 12V were fine. Some head scratching and more measurements later I found that my analogue ground was at +4.25V compared to the digital ground - if I measured the digital voltages with reference to the digital ground they were correct at + and - ~10V and +5V.
I've now re-connected the analogue and digital grounds at the tx, all the voltages measure OK and the CD spins, all display and transport functions are OK in that it does what it should do in response to remote control commands but I've got no sound at all, just some white noise if I turn the volume right up on the amps. I swapped the opamps back to the originals but no joy, exactly the same result, so I don't think I've blown the LM4562's but I don't know what I have killed, aaahhrg!
Two questions for all the gurus out there - Where the hell did that 4.25V difference between analogue and digital grounds come from? And what measurements do I need to make to determine why I have no sound output?
Thanks in advance
Ha ha, it's amazing! I never could have guessed that, it's still going strong after all these years!
I'm still subscribed to this thread of course, but somehow I don't get a notification when a new message has been posted. It seems very irregular at best. Anyone else has this problem?
I don't mind answering questions and helping people out, but it's a bit difficult if I have to keep running after the facts...
Regards,
Raymond
Oh my!
Let's have a party at Ray's house
Great idea, you're all invited! If you bring your gear, I'll handle the beer!
That would be really something, a DIY Audio party in my backyard
Great idea, you're all invited! If you bring your gear, I'll handle the beer!
That would be really something, a DIY Audio party in my backyard
Be careful what you're promising. I think we are a lot still subscribed to this thread
Notifications are ok here.
Great, you're most welcome Martin!
Seriously guys, it's about time we met in real life, don't you think? The more I think about it... we'll have a BBQ if the weather is good, and i'll make a soldering-corner for real-time DIY first aid! But it would have to be a whole-day event, otherwise it's not worth the effort. You'll have to travel to Heerhugowaard, The Netherlands though.
Seriously guys, it's about time we met in real life, don't you think? The more I think about it... we'll have a BBQ if the weather is good, and i'll make a soldering-corner for real-time DIY first aid! But it would have to be a whole-day event, otherwise it's not worth the effort. You'll have to travel to Heerhugowaard, The Netherlands though.
It's pretty impressive!!!
With respect to the questions relating to grounds, they can be separated locally but ultimately they must be connected together. You ended up with one gnd floating which is what caused your issues. Personally, I'd link via a low ohm inductor. Find a service manual online of a player that uses separate analogue and digital supplies and they will be linked via an inductor or resistor. personally I'd create a star for analogue and a star for digital and then link them both together at a single point.
With respect to the questions relating to grounds, they can be separated locally but ultimately they must be connected together. You ended up with one gnd floating which is what caused your issues. Personally, I'd link via a low ohm inductor. Find a service manual online of a player that uses separate analogue and digital supplies and they will be linked via an inductor or resistor. personally I'd create a star for analogue and a star for digital and then link them both together at a single point.