CD104 reads CDRs but not CDs - diyAudio
Go Back   Home > Forums > Source & Line > Digital Source

Digital Source Digital Players and Recorders: CD , SACD , Tape, Memory Card, etc.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 18th May 2013, 06:18 PM   #1
chartz is offline chartz  France
diyAudio Member
 
Join Date: Jul 2009
Location: Burgundy
Default CD104 reads CDRs but not CDs [solved]

Hello,

Well the title says it all.
To see what was done and thought so far, please start from here:

Philips CD104 tweaks

Thanks for your ideas!

Last edited by chartz; 23rd May 2013 at 08:11 PM. Reason: Solved
  Reply With Quote
Old 19th May 2013, 08:20 AM   #2
chartz is offline chartz  France
diyAudio Member
 
Join Date: Jul 2009
Location: Burgundy
Hi!

A though one eh.
Perhaps somebody has the phone number of the Dutch engineer who designed the machine (-;
  Reply With Quote
Old 19th May 2013, 07:39 PM   #3
diyAudio Member
 
PlasticIsGood's Avatar
 
Join Date: Mar 2012
Location: Bradford
I've just measured my own CD104b whilst playing:

CD/CDR eye pattern = 1Vpp/0.7Vpp, pin1 ic6212 = -4V/-5.5V

Yours is ?/1Vpp, 0.25?/-7

Are you sure your CDR eye pattern is 1Vpp, not 0.5Vpp
I note adjustments section of the manual gives pin1 as -4 +/- 2V
  Reply With Quote
Old 19th May 2013, 07:56 PM   #4
chartz is offline chartz  France
diyAudio Member
 
Join Date: Jul 2009
Location: Burgundy
Yes I'm sure.
Now I can't play CDRs! Yesterday I could (even from cold) and today...
What has changed? The radial motor never moves again, it just sticks to the motor spindle as soon as I power up.
In loop A I still measure the same voltages though.
I've ordered a TCA240, we'll see.
  Reply With Quote
Old 20th May 2013, 04:18 PM   #5
chartz is offline chartz  France
diyAudio Member
 
Join Date: Jul 2009
Location: Burgundy
Right then.
I have re-checked, I've got no AC signal at pins 12 and 13 of TCA240 (service loop A), so nothing either (just noise) at pin 8 of 6215 op-amp.
The real question is: what has it worked with CDRs until yesterday? Is it possible that one branch of the TCA still worked and that it finally gave up the ghost?
More of which when it is replaced, I can't wait.
  Reply With Quote
Old 20th May 2013, 04:42 PM   #6
Mooly is offline Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
I admire your determination with this although I still feel the problem will come down to to the RAFOC.

What do Philips call the "focus OK" signal. Have you checked to see if there is any change on that line as the RAFOC does a focus search (with a disc present of course)
__________________
-------------------------------------------------------
Installing and using LTspice. From beginner to advanced.
  Reply With Quote
Old 20th May 2013, 05:24 PM   #7
chartz is offline chartz  France
diyAudio Member
 
Join Date: Jul 2009
Location: Burgundy
I think that the tracking loop doesn't work because the transistors in the TCA are open circuit.
Radial error 1 and 2 signals (the difference is the final tracking error signal) can't find their way to the radial motor.
The error signals from the photodiodes are present and conform.
  Reply With Quote
Old 20th May 2013, 05:31 PM   #8
Mooly is offline Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
Have you scoped and measured voltages on the TCA. Any problems related to one of the six transistors should show in measurement.
__________________
-------------------------------------------------------
Installing and using LTspice. From beginner to advanced.
  Reply With Quote
Old 20th May 2013, 05:34 PM   #9
chartz is offline chartz  France
diyAudio Member
 
Join Date: Jul 2009
Location: Burgundy
Yes I have. Everything comes in nicely but nothing gets out!

Test points 24 and 25 show correct values, but nothing gets out at points 27 and 28, both signals going to the LM324 integrator.

Click the image to open in full size.

Last edited by chartz; 20th May 2013 at 05:39 PM.
  Reply With Quote
Old 20th May 2013, 05:44 PM   #10
Mooly is offline Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
That doesn't necessarily mean its faulty unfortunately. All the evidence is in the voltage and/or dynamic signals present (as viewed on a scope) on those transistors and whatever is present, (whether right or wrong) should enable a good judgement of whether the transistors are functioning correctly.
__________________
-------------------------------------------------------
Installing and using LTspice. From beginner to advanced.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
problems playing last tracks on CDRs? thetube0a3 Digital Source 4 16th March 2012 04:39 AM
What's on your bookshelf -- must reads jackinnj Everything Else 22 7th November 2006 11:50 PM
Burning CDRs trwh Everything Else 9 27th July 2004 05:58 PM
Problems reading CDRs on NEC602 meat Digital Source 3 25th February 2004 08:52 PM
Marantz CD17 reads CDr ? junoman23 Digital Source 4 15th February 2004 10:42 PM


New To Site? Need Help?

All times are GMT. The time now is 03:26 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2