Cambridge CD4SE not reading disks - Please help!

[Pariscratch]

I have a Canbridge Audio CD4SE which I bought new about 4 years ago. I noticed there were a couple of CDs that I bought that it would not read, but did not have the time to deal with it before the hifi went into storage for 3 years. Delighted to get the whole lot out again just ercently and bought some new CDs, but it gives the "no disk" error with three out of five of these new disks, although it works well with all but the other two of my whole collection (to my knowledge).

Is this a simple problem to fix for someone who can follow instructions well, but otherwise has no special electronics kit?

Any help gratefully received. I'm really disappointed not to be able to hear these new disks.

pariscratch

[JohnW]

Try cleaning the Laser Lens (with the unit unplugged from the mains), use cotton buds and distilled water, if this does not help, then it sounds like your going to need to replace the Laser Pickup (CDM12.1).

The unit is based on CD7 Digital Servo - so there are no adjustments (apart from Laser Power on the head).

As its 99% chance that the Lasers on its way out ANYWAY, and if it where MY machine - I would increase the Laser power slightly - but you need to know what your doing - and at your own risk!

John

[Extreme_Boky]

Hi Pariscratch,

Check your PCB and look for a point labelled RF. Monitor the RF signal on oscilloscope and look for an eye-pattern. It should be 1.5(+ or - 0.3) Vp-p. If it is lower than 1.2V you'll have the problem where the pick-up reads some disks, and does not read ones with low reflectivity. You can increase the laser output by adjusting the little trim-pot located on the pickup itself. Do not go over 1.7 - 1.8 volts.

Regards,
Extreme_Boky

[Maxhawk]

Originally posted by JohnW
Try cleaning the Laser Lens (with the unit unplugged from the mains), use cotton buds and distilled water, if this does not help, then it sounds like your going to need to replace the Laser Pickup (CDM12.1).

The unit is based on CD7 Digital Servo - so there are no adjustments (apart from Laser Power on the head).

John

I've got the exact same problem with my CD6. I placed a piece of paper just over the laser to see if it was on, and I got nothing. Shouldn't the laser be visible?

Do you know if the CD6 uses the same pickup as you describe above?

TIA.

[Maxhawk]

I got mine working! My symptom is that when a disc is inserted, the CD spins and you can hear the laser moving up and down, and then it says no disc.

I replaced capacitor C2 (100uF/10V) on the servo board (located near CN8 if yours uses the same controller board) and now the player reads discs fine. I replaced the cap with a Panasonic FC series of the same value (100uF/25V).

So either the old cap was going bad or this lower ESR capacitor is covering up the real problem. While troubleshooting the problem I borrowed a laser power meter from work and verified that the laser did indeed have output. After that I started working backwards on the schematic to see what could be causing the problem. I can email you the CD6 schematic if you want. I imagine the servo boards in the two models are the same.

[JohnW]

Hi Maxhawk,

The CD4SE is based on Philips CD7 / CDM12.1; while your CD6 is based upon Sanyo PU-91 and Samsung chipset (earlier units used Sony chipset).

Well done in solving your issue,

For my reference, could you Pls. Email me the CD6 Circuit.

BR

John

[brokehifinut]

Hello ,
Would it be possible to get a schematic of the CD6?
I got one quite cheap and it does not spin up on discs,but if you close it and spin the disc with your finger it plays.
I have cleaned the lens with isopropyl and a q-tip.
Could it be the same issue that Maxhawk had?

I got mine working! My symptom is that when a disc is inserted, the CD spins and you can hear the laser moving up and down, and then it says no disc.

I replaced capacitor C2 (100uF/10V) on the servo board (located near CN8 if yours uses the same controller board) and now the player reads discs fine. I replaced the cap with a Panasonic FC series of the same value (100uF/25V).

So either the old cap was going bad or this lower ESR capacitor is covering up the real problem. While troubleshooting the problem I borrowed a laser power meter from work and verified that the laser did indeed have output. After that I started working backwards on the schematic to see what could be causing the problem. I can email you the CD6 schematic if you want. I imagine the servo boards in the two models are the same.

This player is lot kinder to the music and ears than my Phillips DI-624 DVD player.I would love to be able to use it as my main player.
Cheers and Thanks,

[rrlean]

Originally posted by brokehifinut
Hello ,
Would it be possible to get a schematic of the CD6?
I got one quite cheap and it does not spin up on discs,but if you close it and spin the disc with your finger it plays.
I have cleaned the lens with isopropyl and a q-tip.
Could it be the same issue that Maxhawk had?



This player is lot kinder to the music and ears than my Phillips DI-624 DVD player.I would love to be able to use it as my main player.
Cheers and Thanks,

I have a similar problem to brokehifinut in that the disc must be spun manually to spin. I've cleaned the lens several times. I would appreciate a copy of the schematic and any advice on what the problem may be. It appears that the motor of the disc spindle (sorry - not sure of the correct terminology) is weak. I also have a problem of getting the tray to open when the unit is first powered on. I'm hoping these are all related issues. Thanks in advance for any assistance.

[gmphadte]

CD spin motor is defective.

Gajanan Phadte