Hello,
My Marantz CD4000 is broken. It loads the CD, then after 5 seconds ejects it.
(it does not spin)
I opened the player, and checked the laser.
The things that happen:
1. The laser does not go "up" to search for the CD
2. The laser is not visible (is that correct, or should the laser be visible)
What can be done with this? I assume the tray is a VAM1201.
Haik
My Marantz CD4000 is broken. It loads the CD, then after 5 seconds ejects it.
(it does not spin)
I opened the player, and checked the laser.
The things that happen:
1. The laser does not go "up" to search for the CD
2. The laser is not visible (is that correct, or should the laser be visible)
What can be done with this? I assume the tray is a VAM1201.
Haik
Make sure that the mechanism fully completes the loading cycle. I'm not familiar with the Marantz but the VAM type pickups usually "lift" to meet the disc. Make sure no loading belts are slipping.
If the laser sled assembly is wound out manually away from the platter then it should automatically return to the rest position when the player is powered up or the tray ejected.
The laser will only be visible during the focus search routine (lens going up and down when tray is closed) and is not easy to see anyway as it's mainly infra red.
So if it is not doing a focus search then the problem doesn't sound laser related.
If the laser sled assembly is wound out manually away from the platter then it should automatically return to the rest position when the player is powered up or the tray ejected.
The laser will only be visible during the focus search routine (lens going up and down when tray is closed) and is not easy to see anyway as it's mainly infra red.
So if it is not doing a focus search then the problem doesn't sound laser related.
Seems not to work.
It works fine with original CD's, but the ones I burned it works sometimes, skips couple of seconds of music, jumps to next track etc... Sometime I see "disk not finalized" (of course it is finalized).
The burned disks work flawlessly in s different Marantz player.
I cleaned the lens, and no difference.
Also, when I press STOP, the CD starts to turn very very fast the WRONG way, and when I open the tray, it is still spinning in the tray. I assume it is the "brake" of the CD player to stop the CD when opening the tray. But it does not stop.
Is it the laser unit? I can get a laser unit for 10-15 euro at ebay. Or is it the electronics below it?
Is it worth?
Haik
Could You do the disc quality test of burned CD-R using kprobe or nero cd-dvdspeed? The problem with "disk not finalized" message is probably related to CDM12/VAM12xx compatibility issue. I have the same problem with one original, pressed CD on my Philips player.
Regards,
f.
Burned CD's vary enourmously from machine to machine.
It would be worth trying a new CDR burned on another PC if possible. The definitive way to test this is to look at the RF signal coming of the disc with a scope on both pressed CD's and burned CDR's. The Marantz may or may not be "marginal"... without proper tests it's impossible to say. If the level is lowish on pressed discs (pointing to a pickup or alignment issue) then with CDR it's almost certain to give trouble.
Burning at the fastest speed is not always the answer too. I tested this on my laptop and the best recovered RF on playback on a standard CD player came from the lower speeds.
It would be worth trying a new CDR burned on another PC if possible. The definitive way to test this is to look at the RF signal coming of the disc with a scope on both pressed CD's and burned CDR's. The Marantz may or may not be "marginal"... without proper tests it's impossible to say. If the level is lowish on pressed discs (pointing to a pickup or alignment issue) then with CDR it's almost certain to give trouble.
Burning at the fastest speed is not always the answer too. I tested this on my laptop and the best recovered RF on playback on a standard CD player came from the lower speeds.
The audio CD must be burned with CLV strategy (max 16x speed). The optimum speed depends on media, too. Some disc are designed as high-speed only. There is no problem with reading good quality and properly burned media on VAM12xx.
f.
Interesting. It worked before. I could play any disk.
Then once upon a time, the CD4000 stopped reading any disks. Then I put the CD player away, and used my old one, the Marantz 67SE. That one eats everything.
Now I want to build in a different DAC, so I started to "repair" the CD4000.
The interesting thing I see, if a CD is played and I press STOP, then the disk start to spin the other way (counter clockwise) very very fast, and does not stop. Then the slide opens with the spinning disk falling on the slide.
Is the electronics that control the motor broken? Al lot of TDA IC's are soldered there. Since they are normal IC's (not SMD's) it is easy to replace them.
Is it an idea to replace them, or is it a processor which controls these IC's which gives wrong commands?
Does anyone have a schematic of the control part of the laserunit?
Is there a shop that sells spare parts for Marantz CD-players? E-bay sellers? Some shop in Europe?
Then once upon a time, the CD4000 stopped reading any disks. Then I put the CD player away, and used my old one, the Marantz 67SE. That one eats everything.
Now I want to build in a different DAC, so I started to "repair" the CD4000.
The interesting thing I see, if a CD is played and I press STOP, then the disk start to spin the other way (counter clockwise) very very fast, and does not stop. Then the slide opens with the spinning disk falling on the slide.
Is the electronics that control the motor broken? Al lot of TDA IC's are soldered there. Since they are normal IC's (not SMD's) it is easy to replace them.
Is it an idea to replace them, or is it a processor which controls these IC's which gives wrong commands?
Does anyone have a schematic of the control part of the laserunit?
Is there a shop that sells spare parts for Marantz CD-players? E-bay sellers? Some shop in Europe?
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The disc spining fast and backwards are symptoms that "servo lock" has been lost. It's not a motor drive fault.
The answer to this is to look with a scope at the signal. Unless you do detailed tests and gather and understand all the information then you are just guessing as to the cause.
CDR's are very "non standard" compared to pressed Red book standard discs.
The answer to this is to look with a scope at the signal. Unless you do detailed tests and gather and understand all the information then you are just guessing as to the cause.
CDR's are very "non standard" compared to pressed Red book standard discs.
Thanks Mooly.
I just got the service manual, and found the places where the signals are coming from the microprosessor to the motor driver.
Since I do not have a scope, I will check with my multimeter, just to see if the signal ends after a second or so, or that that the processor is continuing driving the motor.
If I do not get further, I will get a scope. Or a cheap Philips CD723 player. The 723 and the CD4000 share the same mechanics (and electronics).
Haik
I just got the service manual, and found the places where the signals are coming from the microprosessor to the motor driver.
Since I do not have a scope, I will check with my multimeter, just to see if the signal ends after a second or so, or that that the processor is continuing driving the motor.
If I do not get further, I will get a scope. Or a cheap Philips CD723 player. The 723 and the CD4000 share the same mechanics (and electronics).
Haik
A scope is the best tool for faultfinding.
When the servo loses lock on the CDR's then it's a bit like a computer crashing or locking up. There's no fault as such but nothing works or responds until the processor is reset.
There won't (99.999% sure) be a processor or motor drive fault. It's down to the way it's "seeing" the data on the CDR's.
When the servo loses lock on the CDR's then it's a bit like a computer crashing or locking up. There's no fault as such but nothing works or responds until the processor is reset.
There won't (99.999% sure) be a processor or motor drive fault. It's down to the way it's "seeing" the data on the CDR's.
I'm surprised that a CD player is able to spin backwards. The facility to reverse polarity to the motor must be there for a purpose, presumably for braking?
I'm not an expert, but one purely logical explanation for both problems is that the servo has lost its sense of the motor going too slow. Fast backwards is just an extreme case of too slow. Are CDRs more densely packed, requiring the disc to slow from some nominal speed more than usual? Maybe it then slows too much at the first guess and can't recover. Similarly with the brake, where the "too slow" signal should result in switching off the motor. Long shot...just encouraging positive thought.
If the fault changed as a result of you cleaning contacts, it could be that just handling the board restored a poor connection until either it got warm or was disturbed by the operation of the drawer or laser sled. By the same token the fault is unlikely to be component failure.
Is there somewhere an analogue voltage that represents motor speed error? You could examine that with a voltmeter, and check that errors of both polarities are reaching their intended destination. Look for dry joints or cracked tracks (use a magnifying glass) in that area. Similarly for parts of the servo circuit that get hot or stressed by the mechanics of operation, or handling. Check for hairline cracks in ribbon connectors too.
I've got a Marantz CD50 that's sticks in fast forward every time I replace the front panel. It's driving me mad.
Ian
I'm not an expert, but one purely logical explanation for both problems is that the servo has lost its sense of the motor going too slow. Fast backwards is just an extreme case of too slow. Are CDRs more densely packed, requiring the disc to slow from some nominal speed more than usual? Maybe it then slows too much at the first guess and can't recover. Similarly with the brake, where the "too slow" signal should result in switching off the motor. Long shot...just encouraging positive thought.
If the fault changed as a result of you cleaning contacts, it could be that just handling the board restored a poor connection until either it got warm or was disturbed by the operation of the drawer or laser sled. By the same token the fault is unlikely to be component failure.
Is there somewhere an analogue voltage that represents motor speed error? You could examine that with a voltmeter, and check that errors of both polarities are reaching their intended destination. Look for dry joints or cracked tracks (use a magnifying glass) in that area. Similarly for parts of the servo circuit that get hot or stressed by the mechanics of operation, or handling. Check for hairline cracks in ribbon connectors too.
I've got a Marantz CD50 that's sticks in fast forward every time I replace the front panel. It's driving me mad.
Ian
The next step is this
There is no guarantee that a new pickup will fix this. It may or may not. Without actually confirming the quality of the signal from the laser it's all guesswork.
CDR's are fundamentally different in the way they "reflect" the laser light.
A transistion (which is interpreted as a change from logic 1 to a logic 0) in a normal CD occurs every time there is a change from a "pit" to a "land" on the reflective layer. The pits and lands are equally reflective but due to the wavelength and the monochromatic nature of the laser light, if the lens is "focused" on say the lands, then the light reflected from the pits is not seen by the photodetector sensor as it is seeing the "null" point in the reflected light here. Bit hard to explain easily
A CDR uses a dye that is "burned" to make the pits and lands. There is no reflective property where the dye blocks the light from being reflected. The sensor still sees a transition though.
The problem is that CD's are pressed and have accurately defined pits and lands with clean edges. CDR's are not as precise and the point where the burned dye starts and finishes is not as clean and abrubt change as in the pressed CD's. This show up clearly on the recovered signal when viewed on a scope.
The problem with the front sounds like it's pressing on one of the tact swithes.
I have read the service manual. There is a service menu so you can run the CD player is a test mode.
I tested everything. Spinning CW and CCW. Moving laser to the edge of disk and back. Everything works. The CD accelerates well, and stops also fine. So the signals coming from the processor are good.
What fails is the "FOCUS". It gives an error. There is a way to change the focus by defining CD-R or CD-A disk. Both fail in the test (but in real life, only CD-A originals are working).
I also tested the focus of the laser, and it fails (the going up and down of the laser lens). The lens goes up and down, that works, but does not find the focus. Cleaning the lens did not help.
So I still think the processor gets wrong information, and does not find or know about the CD. That is why it does not stop the reverse spinning.
So Mooly, you might be right. I think I will order the laser unit (especially now in the manual it is shown how to disassemble the mechanical unit).
Haik
I tested everything. Spinning CW and CCW. Moving laser to the edge of disk and back. Everything works. The CD accelerates well, and stops also fine. So the signals coming from the processor are good.
What fails is the "FOCUS". It gives an error. There is a way to change the focus by defining CD-R or CD-A disk. Both fail in the test (but in real life, only CD-A originals are working).
I also tested the focus of the laser, and it fails (the going up and down of the laser lens). The lens goes up and down, that works, but does not find the focus. Cleaning the lens did not help.
So I still think the processor gets wrong information, and does not find or know about the CD. That is why it does not stop the reverse spinning.
So Mooly, you might be right. I think I will order the laser unit (especially now in the manual it is shown how to disassemble the mechanical unit).
Haik
Thanks.
Sorry, I mean the motor runs forward, fast. Not like pressing the fast forward key. The buttons all click and work as far as expected with no CD loaded and the motor permanently running. It's not an earthing thing either, and the boards are all seated properly and appear relaxed.
Having solved the problems it had when I got it, I'm now upset and it's in disgrace. I'll look at it again when I feel calmer. Thanks all the same.
Ian
I think we agree that the processor is not getting the right information. The problem is why not.
I'm surprised that the machine relies entirely on feedback from the laser to determine its spin speed. I'd assumed two nested loops, with the inner one derived from the motor itself. Oh well...logic isn't always the best guide.
I'm new to CD players, which is why I'm here, so I'm learning, thanks.
So, if a player of this kind loses focus whilst playing a CD, it's normal for it to go into a fast reverse spin if "stop" is pressed?
Ian
I'm surprised that the machine relies entirely on feedback from the laser to determine its spin speed. I'd assumed two nested loops, with the inner one derived from the motor itself. Oh well...logic isn't always the best guide.
I'm new to CD players, which is why I'm here, so I'm learning, thanks.
So, if a player of this kind loses focus whilst playing a CD, it's normal for it to go into a fast reverse spin if "stop" is pressed?
Ian
Without a scope that is probably all you can realistically do... lets hope it's a fix.