Philips CDM-1

[Elso Kwak]

Hi Eric,
Thanks a lot for the help.
The spindle motor is a standard DC brush motor. Well standard? I checked for the motor in four abandoned players but these had other models. Today I will order a new motor.
Eyepattern from the laser is abosolutely perfect and focus and tracking gain adjustment don't change it. I also checked the solderjoints and powersupplies. The lasercarriage has very low friction now as it moves when the player is tilted only a few degrees.
BTW I have only one rail. The other end of the carriage rest on a wheel!
Guido, I am sorry, your are totally wrong. At track one the disc spins at highest speed at track 70 it spins at lowest speed!

[mrfeedback]

Elso, you can fix the spin motor, usually.
The normal failure mode is that the commutator goes noisey contacts.
The soloution is as follows - load a disc into the mech.
Disconnect motor wires and connect motor to a DC supply (6V or so) momentarily until speed is up to normal high speed (500 rpm) and then quickly reverse the polarity so that the disc slows down and then reverses direction back upto 500 rpm or so, and reverse the supply again - a reversing switch is a good tool here.
Do this spin-up and reversal at least several times to clear and renew the commutator contacts, and you should be ok.
The commutator contacts go sour due to low currents and low voltages in normal operation.
RF-310 motors and a few others commonly go bad like this, and the symptoms are no disc rotation due to motor parking on a bad spot, or especially in Pioneer players, slow spin up to speed and therefore no TOC loading, or if it does play, when getting to end of disc (200 rpm) speed stability suffers and the buffer memory empties giving gated audio output, mistracking, or the player spits the dummy and displays 'no disc'.

Eric.

[guido]

Elso, others,

Sorry, wrote something without checking... You are right!

You most probably know this, but to set things right for others who are mislead by my earlier comment:

Density is equal (pits have the same size) on the whole of the disk. Therefore the disk needs to spin
slower at the edge (one rev gives more pits/data on the outside than the inside).
This way a constant transfer rate is obtained. Inside ~539 RMP, outside ~210 RPM.

Will check things a better in the future. Can't help you on the Sony, i have no experience with those
(only my own philips).

Happy New Year!

Guido B.

[mrfeedback]

Elso, can you post a pix of the mech and pcb ? - then I know which machine we are talking about - the model number does not ring a bell right now, but that does not mean anything - mech and pcb pictures will.
Anyway, if your machine has a PLL oscillator coil with adjustable ferrite slug for center frequency, then if the free run frequency is too far out, then you will get symptoms like you describe - 'no disc' when track jumping - dodgy spin motor can cause this too - see above post.
Another method is a PLL trimpot, and some machines have no adjustment.
If you need to adjust PLL center frequency, ask and I'll tell you how.

Eric.

[Elso Kwak]

Hi Eric,
I ordered and replaced the spindle motor. It came with a large chunck of gray plastic and I had to break of two pillars to make it fit. It was for the CDP-X339ES. And I ordered for the CDP-X33ES or CDP-X333ES.
The track jump is still not fast enough but it reaches the track without going into error.
Another very weird phenomenon occurred:
When cold and power applied the player goes into play mode on power on (autoplaymode) but runs 10 seconds at <B><I>half</B></I> speed; then speeds up and sound goes dead, then a loud noise comes from the speakers and eventually it sounds OK in the middle of track 1.
When the CDP is on for a few minutes this strange behavior does not occur. I suspect the PLL, but how do I get it better?
Even more weird: sound is <B>much</B> better than with the old laser. Both are KSS271A.
I am sorry I have no picture. This CDP does not have a adjustable PLL. It uses CXA1372 and CXD2500Q

[mrfeedback]

"This CDP does not have a adjustable PLL."
Ok, this is not the problem then.

Elso, in my experience I do not trust soldering on the flatpack smd packages, and resoldering these has cured a lot of problems for me in the past.
Perhaps you need to check and adjust servo DC offsets, and maybe increase tracking and focus gains.
Apart from that I have not seen the fault that you describe.

Eric.

[Elso Kwak]

Originally posted by mrfeedback
[b
Elso, in my experience I do not trust soldering on the flatpack smd packages, and resoldering these has cured a lot of problems for me in the past.
Perhaps you need to check and adjust servo DC offsets, and maybe increase tracking and focus gains.
Apart from that I have not seen the fault that you describe.

Eric.

Hi Eric ,
Thanks a lot for the help. This is also my experience. Very often these SMD IC's are badly soldered. I also have the impression that the soldertype used by Sony gets worse over time. It looses its shine and when heated it does not flow. Weird. I repaired my TV-set by resoldering . Will see if it helps my CDP. Thanks again.

[Elso Kwak]

Hi Eric,
I resoldered the PLL lowpassfilterside of the CXD2500Q.
I exorcized the crazyness!
Thanks a lot!

[chris ma]

Hi all,
I have a old brand new vcd cd mp3 player that when power on, insert a cd, close the tray, then the cd disc only spin a third of a turn and stop spinning. The the laser assembly was moving up and down and then the display says no disc.
I have used 4 of 1.5V AA batteries to test the spinning motor and it spins ok. Where else I should look into to find the fault.
Thanks,
Chris

[mrfeedback]

Originally posted by Elso Kwak
Hi Eric,
I resoldered the PLL lowpassfilterside of the CXD2500Q.
I exorcized the crazyness!
Thanks a lot!

Hey, now in addition to tuning televisions and vcrs by telephone, I can now repair CD players by internet.
No wuckin' furries, my pleasure and glad to be of help.
BTW if you resolder that chip with say 96S you will get a different (I reckon nicer) sound and LMP stuffs it up (imo).

Eric.

Sorry to give you more homework.