Hi all,
First post in this forum. I've already read a lot of posts in this forum trying to find the answer to my problem. But unfortunately no luck yet...
This might well be that I miss some expert experience (or that I am still rookie or novice
).
Heres my problem I want to share with you:
I have got a very nice CD player wich is build around a CDM4/31 CD unit. Until recently everything worked as it should, but suddenly the trouble started.
When I place a disc (original or CDR) the laser goes to the middle of the disc, meanwhile the disc starts spinning, the laser goes on and of for a couple of times and you can see the lens moving up and down (trying to focus?).
BUT the disc continues spinning, spinning faster and faster. Haven't seen a regular audio CD player at the speed ever... I checked all (ELCO) capacitors and replaced most of them, just in case.
I resoldered some suspective joints. Still no improvement.
I haven't touched the adjustments yet as I do not have a scope. Nor do I have the manual for the correct settings.
I am wondering if there might be something I am overlooking (I read somewhere that some sort of clock can do such a thing, but couldn't really find it on my little print). Might there be any particular component worth checking in detail?
Is this unit in need of replacement or are there options left to try to repair it?
If someone needs more detailed information, please let me know and I'll try to give as much detail as needed or possible.
Thanks in advance to all.
First post in this forum. I've already read a lot of posts in this forum trying to find the answer to my problem. But unfortunately no luck yet...
This might well be that I miss some expert experience (or that I am still rookie or novice
). Heres my problem I want to share with you:
I have got a very nice CD player wich is build around a CDM4/31 CD unit. Until recently everything worked as it should, but suddenly the trouble started.
When I place a disc (original or CDR) the laser goes to the middle of the disc, meanwhile the disc starts spinning, the laser goes on and of for a couple of times and you can see the lens moving up and down (trying to focus?).
BUT the disc continues spinning, spinning faster and faster. Haven't seen a regular audio CD player at the speed ever... I checked all (ELCO) capacitors and replaced most of them, just in case.
I resoldered some suspective joints. Still no improvement.
I haven't touched the adjustments yet as I do not have a scope. Nor do I have the manual for the correct settings.
I am wondering if there might be something I am overlooking (I read somewhere that some sort of clock can do such a thing, but couldn't really find it on my little print). Might there be any particular component worth checking in detail?
Is this unit in need of replacement or are there options left to try to repair it?
If someone needs more detailed information, please let me know and I'll try to give as much detail as needed or possible.
Thanks in advance to all.
Thanks for the quick replies,
I checked on the transistors. At least 1 is suspicious. I am not sure which type I can use to replace them. They seem not so common. If I am correct it reads C32825 and then somthing wich seems PH21 or PH27 or so...
As far as the resistors are concerned I already replaced 2x a 10 Ohm resistor as they have been hot hot hot in the past. At least thats what the colour on the print indicates
Just a question about the clock
, is there any indication I can look for on the print. I do not have a manual for this Cd player. On the print a lot of indications (2 letter abbreviations) are given, but I cannot determine which one should be the clock.
There are 3 big IC's on the print maybe some pin nrs. to check:
- Philips TDA5709
- Motorola TCA0372DP2
- Philips TDA5708
I checked on the transistors. At least 1 is suspicious. I am not sure which type I can use to replace them. They seem not so common. If I am correct it reads C32825 and then somthing wich seems PH21 or PH27 or so...
As far as the resistors are concerned I already replaced 2x a 10 Ohm resistor as they have been hot hot hot in the past. At least thats what the colour on the print indicates
Just a question about the clock
, is there any indication I can look for on the print. I do not have a manual for this Cd player. On the print a lot of indications (2 letter abbreviations) are given, but I cannot determine which one should be the clock. There are 3 big IC's on the print maybe some pin nrs. to check:
- Philips TDA5709
- Motorola TCA0372DP2
- Philips TDA5708
if it's a philips setup, clock is generated by 7220 and fed to 7210. The 7210 controls the diskmotor. If the clock is absent, the 7210 puts the disk at warpspeed. I had one fly out once, when i was working on a player with the clamp removed. Scary
So it's the clock, the 7220, 7210 or the driver transistors your looking at which might be faulty.
Fixing this with trial and error is not a good idea. If you break another thing, chances are you wont get it working again with two faults.
Now, what make and model are we talking about and how far south do you live?
So it's the clock, the 7220, 7210 or the driver transistors your looking at which might be faulty.
Fixing this with trial and error is not a good idea. If you break another thing, chances are you wont get it working again with two faults.
Now, what make and model are we talking about and how far south do you live?
The laser still gives some sort of a ray of light. Can it still be defective?
How can I sort out what is the main cause of the problems?
- dead laser
- bad timer (conection between the 2 IC's seems OK, don't know if the oscilator at 11.xxMHz has broken?)
- bad transistor (As the 10Ohm resistor was burnt en now replaced. Only not the transistor as I do not have a compatible one. At least not that I know), C32825.
How can I sort out what is the main cause of the problems?
- dead laser
- bad timer (conection between the 2 IC's seems OK, don't know if the oscilator at 11.xxMHz has broken?)
- bad transistor (As the 10Ohm resistor was burnt en now replaced. Only not the transistor as I do not have a compatible one. At least not that I know), C32825.
OK, thanks!
Now the big question, is there any way to check it? or just replace?
Might be worth to exchange the complete unit. Haven't really found these units. (Only one... and I am not sure if it is incuding the electronics, or just a laser with some mechanical parts, and without motor).
If there are good resources I am obviously very intersted. Or any other hint that may lead to a successful repair!
Now the big question, is there any way to check it? or just replace?
Might be worth to exchange the complete unit. Haven't really found these units. (Only one... and I am not sure if it is incuding the electronics, or just a laser with some mechanical parts, and without motor).
If there are good resources I am obviously very intersted. Or any other hint that may lead to a successful repair!
Breda is far far north for me
You can use trial and error and start replacing bits and pieces, but measuring could be the better option.
There are nice scope's on marktplaats for little money. Won't hurt to get one and measure before replacing.
As for the 4/31: the components used (and the stuff on the mainboard) are in any cheap philips player of the correct eara. Which are 15 euro's at the kringloop (here).
Replace something badly or with a bad component and you've got two faults. Then try to find them both....
You can use trial and error and start replacing bits and pieces, but measuring could be the better option.
There are nice scope's on marktplaats for little money. Won't hurt to get one and measure before replacing.
As for the 4/31: the components used (and the stuff on the mainboard) are in any cheap philips player of the correct eara. Which are 15 euro's at the kringloop (here).
Replace something badly or with a bad component and you've got two faults. Then try to find them both....
No,
But a 4/19 player uses the same components, just all is on the main pcb.
As for 4/31's, not so much used. It's basically a replacement for the cdm2 transport (drop-in). There was a sale some time ago here, you've misted it
So... Get a cdm4/x player on marktplaats/kringloop for peanuts and then practice on it with that scope. Then find the problem in the b&o and fix it.
There are plenty of manuals available with that chipset, so you know what and where to measure.
A laser-swap is also possible between 4/19 and 4/31 if it is just that.
But a 4/19 player uses the same components, just all is on the main pcb.
As for 4/31's, not so much used. It's basically a replacement for the cdm2 transport (drop-in). There was a sale some time ago here, you've misted it
So... Get a cdm4/x player on marktplaats/kringloop for peanuts and then practice on it with that scope. Then find the problem in the b&o and fix it.
There are plenty of manuals available with that chipset, so you know what and where to measure.
A laser-swap is also possible between 4/19 and 4/31 if it is just that.
Thanks for the info! I'll keep you informed.
Just one thing that I might have missed. I thought a CDM4.19 had a different CD motor?
I am in doubt now, I was quite convinced that I had a CDM4/31. (Only two wires for the CD motor, and I thought CDM4/19 had a different one, 4 wires, Hall?). But if components are still the same, I'll give it a go. I've seen a lot of them near me! (Also CDM4/11 players, are these also compatible?)
Thanks
Just one thing that I might have missed. I thought a CDM4.19 had a different CD motor?
I am in doubt now, I was quite convinced that I had a CDM4/31. (Only two wires for the CD motor, and I thought CDM4/19 had a different one, 4 wires, Hall?). But if components are still the same, I'll give it a go. I've seen a lot of them near me! (Also CDM4/11 players, are these also compatible?)
Thanks
guidovangool said:
Hall is expensive to make
So when it could be done cheaper, they used the toymotor. So up to 4/11 is hall, rest isn't (with exceptions i guess)cdm2, cdm4/11 are hall, 4/19 and 4/31 aren't.
Left to right: cdm2, 4/11, 4/19 and 4/31. cdm2 and 4/31 come with own pcb.
basically a 4/11 looks like the 2 without the pcb and the 4/31 like the 2, but without the hall.
If your disk is spinning, the motor is fine. But the other components (decoder,filter,radial,laser) are equal.
GuidoB
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CDM-4 Transistors
"checked on the transistors. At least 1 is suspicious. I am not sure which type I can use to replace them. They seem not so common. If I am correct it reads C32825 and then somthing wich seems PH21 or PH27 or so..."
Hi guidovangool
This transistor is a BC325/25 = 25 is for tr' HFE
PH is for Philips
I replace the 2 transistors : one NPN and one PNP.
Just replace them with 2SB647 and 2SD667.
These transistors fail because of bad motor brushes.
Hope this can help if your problem is a motor one.
"checked on the transistors. At least 1 is suspicious. I am not sure which type I can use to replace them. They seem not so common. If I am correct it reads C32825 and then somthing wich seems PH21 or PH27 or so..."
Hi guidovangool
This transistor is a BC325/25 = 25 is for tr' HFE
PH is for Philips
I replace the 2 transistors : one NPN and one PNP.
Just replace them with 2SB647 and 2SD667.
These transistors fail because of bad motor brushes.
Hope this can help if your problem is a motor one.
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