Philips CD303 with distortion and noise - 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 23rd August 2008, 07:24 AM   #1
diyAudio Member
 
Join Date: Aug 2008
Default Philips CD303 with distortion and noise

Hello,
I have trouble with my loved CD303, and just can't help myself.
For the story, I acquired it for over1 1/2 year and until a couple of days it was perfectly working. Just a problem with the tray that would't fully close or open since 6 monthes.
Now for the problem: I was listening to some music as the player gave some loud noises from itself. The noise was very short, about 2 sec abd the kind of one which goes under your skin and that you can feel in your whole body. After this the player stopped. Turned it on and off a couple of times didn't changed anything: it just didn't wanted to spin. Until I pressed the tray. The cd was spinning and started to play again. As I was in hurry, I didn't payed attention to anything else.
Next day, I wanted to listen to some cds: The right channel just outputed some distortion noise, left channel had no problem. After left it warm up for 30 min or so, the distortion "ALMOST" disappeared. I said almost because you still can hear it on quiet passages and by carefully listening. On top of this: the right channel has very very low bass in comparisom with the left channel.
Yesterday, as I turned it on, there were some blank noise: no cd inserted, but the loudspeakers were crying... I had no scope o it, but "fortunatly" an equalizer: the noise on the high frequencies is almost continous, and periodical in the bass range (in case it could help someone for diagnostic!).
After a little warm up, the noise disappeared. But the right channel still has distortion and almost no bass output.
I thought on a cold joint, but not sure and I don't know of to start with this unit. So I would appreciate every help!
Thank you a lot!

ps: I searched the forum, found some treads about joint problems, but I couldn't help myself with them...
ps2: sorry for my english :/
  Reply With Quote
Old 23rd August 2008, 08:16 AM   #2
poynton is offline poynton  United Kingdom
diyAudio Member
 
poynton's Avatar
 
Join Date: Mar 2005
Location: A life on the ocean waves when I'm not at home in N. Wales (but I'm not Welsh so no sheep jokes!)
This sounds very much like one or more dry joints, probably in the power supply.

It would be a good idea to overhaul the PSU board with new capacitors in any case, checking for dry joints as you do the work.
It is not necessary to use "top quality" (expensive) capacitors in order to get the player working.

Warning. Do the power supply board only first. Do not replace parts on other boards as you may introduce faults there makinf future troubleshooting more difficult.

Andy
__________________
If it ain't broke, break it !! Then fix it again. It's called DIY !
  Reply With Quote
Old 23rd August 2008, 09:43 PM   #3
diyAudio Member
 
Join Date: Aug 2008
Thanks for your answer! I just resoldered most of the joint, it doesn't change anything. I'll do the rest as soon as I have a little bit time
Another question: on the heatsink, 5 transistors are mounted. 4 have a silver backplate, but the second from left looks gold. Could it be that this one is burnt out?
  Reply With Quote
Old 24th August 2008, 04:04 AM   #4
poynton is offline poynton  United Kingdom
diyAudio Member
 
poynton's Avatar
 
Join Date: Mar 2005
Location: A life on the ocean waves when I'm not at home in N. Wales (but I'm not Welsh so no sheep jokes!)
Quote:
Originally posted by _Attila_
Thanks for your answer! I just resoldered most of the joint, it doesn't change anything. I'll do the rest as soon as I have a little bit time
Another question: on the heatsink, 5 transistors are mounted. 4 have a silver backplate, but the second from left looks gold. Could it be that this one is burnt out?

It would help if you posted a photo so we can see what you mean.

Andy
__________________
If it ain't broke, break it !! Then fix it again. It's called DIY !
  Reply With Quote
Old 24th August 2008, 07:04 AM   #5
diyAudio Member
 
Join Date: Aug 2008
Ok, here are 2 pics from what I mean: pic1 and pic2.
On the pics, the left transistor has a dark gold/light brown color on its metal plate, the right one has the "normal" silver color. The one with the dark color color is the second from left when facing the open unit (tray is then front left!). The 4 other (eg. 1st, 3rd, 4th and 5th if counting from left and facing the opened unit) have the silver color!

Click the image to open in full size.

Click the image to open in full size.

Now, another question: on the next 3 pics, you can see some solder joints. These are as I found them! Are they "normal" (factory joins), are as my unit been modified? They really look ugly, and for now I din't do anything to them!

Click the image to open in full size.

Click the image to open in full size.

Click the image to open in full size.

What do you think?
  Reply With Quote
Old 24th August 2008, 07:10 AM   #6
Mooly is offline Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
Is the "no bass" a clue. A coupling cap perhaps or open circuit print somewhere. If the left channel is OK that's a big clue.
  Reply With Quote
Old 24th August 2008, 07:15 AM   #7
Mooly is offline Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
I see you are probably still under moderation
Do you have a manual ? If you can isolate (unsolder) the left and right outputs from the DAC to the output filters (OpAmps) and just swap them over. See if the fault transfers to the other channel. Do you actually have a 'scope there ?
  Reply With Quote
Old 24th August 2008, 07:25 AM   #8
poynton is offline poynton  United Kingdom
diyAudio Member
 
poynton's Avatar
 
Join Date: Mar 2005
Location: A life on the ocean waves when I'm not at home in N. Wales (but I'm not Welsh so no sheep jokes!)
It does look as if someone has resoldered some joints previously.

In post 1, did the noise at switch on come from both channels or only the right?

Andy
__________________
If it ain't broke, break it !! Then fix it again. It's called DIY !
  Reply With Quote
Old 24th August 2008, 07:41 AM   #9
diyAudio Member
 
Join Date: Aug 2008
Ok, here we go:
unfortunatly I don't have the service manual, and for now I just can't afford it
The left channel works normal, nice deep and clear bass, no crack, hiss or distortion.
The right channel has a lower output, very distorded. It sounds like if it was "hanging" on the cd (don't know if you understand what I mean: sometimes my car cd-player hangs for 1 or 2 seconds on a track, producing a very high noise, totaly distorted, which is going directly in your nerves ).
Saddly I don't have a scope, maybe (but really MAYBE!) I could get one from work for an evening!
Mooly, could you please be more precise? Maybe a diagram?
Poynton: I can't remember, I was focused on the right channel, so I didn't payed great attention to what was coming from the left.. saddly! For now, I don't have this noise when I power the cd player on. It's really quiet, right and left channels

BTW: how to gain access to the main electronic? I can't open the surrounding without damaging it, what I really would avoid! Any hint?
And I must admit, I feel more conrotable with good old solid state amplifiers or receivers than with that baby here...
  Reply With Quote
Old 24th August 2008, 07:50 AM   #10
Mooly is offline Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
Hi,
Have you tried searching for a manual on the forums -- someone must have one !! If the left channel is OK that means 95 % of the player is working normally. It really does sound like something silly. A PSU problem would affect both channels.
Just re-reading post #1. For the player to stop ( on it's own ? ) then that does sound like something else. Those two things, left channel OK and Right distorted and stops on it's own don't seem related really. No spillage or anything -- cats seen it many times.
  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
PHILIPS CD player CD303 nick83 Digital Source 11 25th May 2010 01:11 AM
Philips cd303 dariusku Digital Source 2 3rd October 2009 05:32 AM
Philips cd303 vkneze13 Digital Source 2 2nd October 2009 09:38 PM
I've murdered my Philips CD303! suddy Digital Source 9 2nd October 2009 09:35 PM
help!i need a manual of philips cd303! falcon4 Digital Source 8 2nd October 2009 09:29 PM


New To Site? Need Help?

All times are GMT. The time now is 03:32 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