Hi, My problem is that my 8se will not play cds. The laser goes to the outside end of rail and bobs up and down very quickly. I replaced the laser assy but it didn't help. Someone with a similar problem suggested it may have something to do with timing and the clock on the dac board. I replaced the reg that looked like it may have overheated, but to no avail. I have a Roksan dac and connected that up but it didn't help. Can I remove the internal dac or does the player need this even when using an external dac? If anyone can help I would greatly appreciate it. I'm a beginner so simple words please. Thank you. Barry
Hello, The regulator may be a red herring. The circuit board was a bit browner under it and I was told it could cause the problem. It supplies the crystal which is on the dac board. I wondered if I could remove the board altogether and use an external dac to prove it is or isn't the dac board.
Hi Mooly, It hasn't been played with or tweeked. It just decided to run to the end of the sled and the laser jumps up and down very quickly. If I move the laser to the centre it just goes back to the edge. Two other people have now told me it has something to do with the clock which is on the dac board, that is why I wondered if I removed the dac board and used my roksan dac, would the clock on that make it work. Barry
Hi.
These symptoms definately indicate that the transport is recieveing no clock. DO NOT RUN THE SYSTEM FOR ANY LENGTH OF TIME LIKE THIS! it will burn out the laser. When doing the check listed below avoid running the system for longer than about 10 seconds at a go.
The first thing to check is that the cable connecting the DAC to the main PCB hasn't come loose. So gently push it into its socket and see if there is any movement. Retest the system quickly. Then try removing it and replacing it carefully. Retest again.
If this doesn't work then, if you have acess to a multimeter check the output of Z11 on the DAC board this should be 5V. This is the power to the clock. If it is no good then and there is power to the input of Z11 then replace Z11.
If this is OK try to get hold of a scope off of someone. Then check the signal on C38 if you do not see a 16MHz signal here then either Q5 could have failed or the crystal could have failed. Q5 you can get from anywhere its a BC847B however the crystal will be difficult to get hold of as it is a 16.9344MHz crystal and they are only used in CD players with a 384x clock (and most have a 256x clock). If you contact ARCAM they will probably sell you one they are quite good like that, but expect to pay quite alot for it probably £10 or so.
Best of luck,
Andrew
These symptoms definately indicate that the transport is recieveing no clock. DO NOT RUN THE SYSTEM FOR ANY LENGTH OF TIME LIKE THIS! it will burn out the laser. When doing the check listed below avoid running the system for longer than about 10 seconds at a go.
The first thing to check is that the cable connecting the DAC to the main PCB hasn't come loose. So gently push it into its socket and see if there is any movement. Retest the system quickly. Then try removing it and replacing it carefully. Retest again.
If this doesn't work then, if you have acess to a multimeter check the output of Z11 on the DAC board this should be 5V. This is the power to the clock. If it is no good then and there is power to the input of Z11 then replace Z11.
If this is OK try to get hold of a scope off of someone. Then check the signal on C38 if you do not see a 16MHz signal here then either Q5 could have failed or the crystal could have failed. Q5 you can get from anywhere its a BC847B however the crystal will be difficult to get hold of as it is a 16.9344MHz crystal and they are only used in CD players with a 384x clock (and most have a 256x clock). If you contact ARCAM they will probably sell you one they are quite good like that, but expect to pay quite alot for it probably £10 or so.
Best of luck,
Andrew
Without seeing a circuit it's guesswork really.
The fact the laser bob's up and down (you mean the proper focus search routine ?) to me suggests the clock is probably present. The disc (platter) often takes off at a million rpm too when that is missing which you haven't mentioned.
Having said that as gfiandy say's, you have to confirm it's there
An external DAC feeds nothing "back" to the player. The player at all times uses it's own clock etc.
Practical experience say's "look for parts that are stressed" which means anything that runs hot etc.
You MUST check every single rail from the PSU and any sub regulators or transistors used for power switching. "Safety" resistors are another common problem. These are low value (usually less than 10 ohm) that work as fuses but they can often go high in value.
If it is purely the sled problem, then an "H bridge" driver is suspect. That is a device (IC or discrete) that can apply voltage to the motor with either polarity form a singe rail supply.
The fact the laser bob's up and down (you mean the proper focus search routine ?) to me suggests the clock is probably present. The disc (platter) often takes off at a million rpm too when that is missing which you haven't mentioned.
Having said that as gfiandy say's, you have to confirm it's there
An external DAC feeds nothing "back" to the player. The player at all times uses it's own clock etc.
Practical experience say's "look for parts that are stressed" which means anything that runs hot etc.
You MUST check every single rail from the PSU and any sub regulators or transistors used for power switching. "Safety" resistors are another common problem. These are low value (usually less than 10 ohm) that work as fuses but they can often go high in value.
If it is purely the sled problem, then an "H bridge" driver is suspect. That is a device (IC or discrete) that can apply voltage to the motor with either polarity form a singe rail supply.
Hi Mooly,
I know you are trying to help but just dismissing my advice with no evidence isn't helping.
I am not guessing, I worked for ARCAM, and I know the symptom this player has (The laser doesn't usually bob in this situation it normally flicks up and down quite quickly, its different to the slower search routine of a laser focusing). When the Sony mech recieves no clock this is exactly what it does, there is quite alot of inteligence in the mech itself as it also contains all the digital servo control electronics, however it does not contain the clock as this needs to be placed near to the DAC, so it is passed back to the servos.
Without the clock the servo controller does not behave correctly and the symptoms described are the most common action it takes. So it could have been a problem with the servo control board but this is unlikley, it is much more likely that the clock is not getting to the laser assembly for some reason and the most likely reason for this is either the connector is loose or the clock has failed (the crystal can end up a little overdriven in this circuit so does sometime fail after a long time).
An external DAC cannot supply the clock signal that is required, you need to fix the on board DAC. It is possible that there might be a crystal in an external DAC board that you could remove and fix the internal DAC with however this would be a expensive fix and not guaranteed as most DACs use a 256x clock 11.2866MHz not the 384x 16.6344MHz used in the 8SE. This is a Sony "standard", so if you have an old sony CD player you may be able to use the crystal from that.
If you are lucky it is just possible that you have one of the 8 SE players that was made by modifying a 7 SE in which case the old 7 SE crystal will be on the main PCB (it looks identical to the crystal on the DAC PCB). If this is the case then you can remove the crystal and fix the 8SE DAC; if it is the crystal that has failed.
However I would not try any of this without investigating the problem as decribed first if it is not any of the simple problems then you need an oscilloscope. If you are not confident to try this then I would recomend either sending it back to ARCAM, although at this point it is probably worth less that they would need to charge to fix it, or find an electronic engineer who is happy to have a go and give him my description.
Regards,
Andrew
I know you are trying to help but just dismissing my advice with no evidence isn't helping.
I am not guessing, I worked for ARCAM, and I know the symptom this player has (The laser doesn't usually bob in this situation it normally flicks up and down quite quickly, its different to the slower search routine of a laser focusing). When the Sony mech recieves no clock this is exactly what it does, there is quite alot of inteligence in the mech itself as it also contains all the digital servo control electronics, however it does not contain the clock as this needs to be placed near to the DAC, so it is passed back to the servos.
Without the clock the servo controller does not behave correctly and the symptoms described are the most common action it takes. So it could have been a problem with the servo control board but this is unlikley, it is much more likely that the clock is not getting to the laser assembly for some reason and the most likely reason for this is either the connector is loose or the clock has failed (the crystal can end up a little overdriven in this circuit so does sometime fail after a long time).
An external DAC cannot supply the clock signal that is required, you need to fix the on board DAC. It is possible that there might be a crystal in an external DAC board that you could remove and fix the internal DAC with however this would be a expensive fix and not guaranteed as most DACs use a 256x clock 11.2866MHz not the 384x 16.6344MHz used in the 8SE. This is a Sony "standard", so if you have an old sony CD player you may be able to use the crystal from that.
If you are lucky it is just possible that you have one of the 8 SE players that was made by modifying a 7 SE in which case the old 7 SE crystal will be on the main PCB (it looks identical to the crystal on the DAC PCB). If this is the case then you can remove the crystal and fix the 8SE DAC; if it is the crystal that has failed.
However I would not try any of this without investigating the problem as decribed first if it is not any of the simple problems then you need an oscilloscope. If you are not confident to try this then I would recomend either sending it back to ARCAM, although at this point it is probably worth less that they would need to charge to fix it, or find an electronic engineer who is happy to have a go and give him my description.
Regards,
Andrew
Hi, Thank you very much both of you. Now I am understanding. So the clock on the on-board dac has to remain because that talks to the laser. I replaced Z11, as that was the reg someone indicated could be the fault. The printed board it sits on is darker like it may have overheated, but it seems not. The two capacitors and crystal are very close also. I changed one of the caps as I had one hanging around. On the main board near the outputs there was also a darkened bit of board under a cap next to a relay so I changed that also. I will do the checks you suggest but I have no access to a scope. Could it be that the regulator burned out and screwed the crystal? I hope not if they are hard to find. I will do the checks and get back. Thanks alot Barry
Hi Barry,
Hi this means that there is no power getting to this regulator. Which may be good news as it probably means the crystal is ok and the other bits are easier to get.
Find Q6 it is a BC847 (I think this means its a surfaced mounted SOT23 part) and check the voltage on it to ground. You can find ground easly on the phono connectors on the back the exposed gold is ground. You should see voltages arround 18v a bit less on one side. If you see 18v on one side and 2v on the other then Q6 has probably failed. If it does not have 18V on one side of it then the 18v supply has failed and this is on the main PCB. Probably one of the regulators you described as being a bit brown.
If that is the case let me know and I will try and track down the circuit for the main PCB. If this is a power problem we can probably find it with just your multimeter.
Regards,
Andrew
Hi this means that there is no power getting to this regulator. Which may be good news as it probably means the crystal is ok and the other bits are easier to get.
Find Q6 it is a BC847 (I think this means its a surfaced mounted SOT23 part) and check the voltage on it to ground. You can find ground easly on the phono connectors on the back the exposed gold is ground. You should see voltages arround 18v a bit less on one side. If you see 18v on one side and 2v on the other then Q6 has probably failed. If it does not have 18V on one side of it then the 18v supply has failed and this is on the main PCB. Probably one of the regulators you described as being a bit brown.
If that is the case let me know and I will try and track down the circuit for the main PCB. If this is a power problem we can probably find it with just your multimeter.
Regards,
Andrew
Hi Andrew,
I'm sorry if you thought I was dismissing your advice, that wasn't my intention at all.
Checking all rails is the first thing on any piece of equipment, and seeing if a proper focus search routine is performed another, however as you have worked for Arcam you have the advantage on me, in knowing that this is a stock fault on this model, and exactly which component fails, and hopefully why. Was there a technical bulletin issued detailing changes to prevent this happening again I wonder.
I'm sorry if you thought I was dismissing your advice, that wasn't my intention at all.
Checking all rails is the first thing on any piece of equipment, and seeing if a proper focus search routine is performed another, however as you have worked for Arcam you have the advantage on me, in knowing that this is a stock fault on this model, and exactly which component fails, and hopefully why. Was there a technical bulletin issued detailing changes to prevent this happening again I wonder.
Hello Barry, without wishing to upset Andrew the BC847 is a common surface mount transistor,
http://www.datasheetcatalog.org/datasheet/vishay/85115.pdf
It's duff with the readings you give assuming 18v is on the collector (centre) and 16v is on the base and 2volt on the emmitter. Check the data sheet for the pin outs and confirm.
http://www.datasheetcatalog.org/datasheet/vishay/85115.pdf
It's duff with the readings you give assuming 18v is on the collector (centre) and 16v is on the base and 2volt on the emmitter. Check the data sheet for the pin outs and confirm.
If you are confident to remove it, you can either replace with same,
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or temporarily fit a full size part if space allows, perhaps drilling the pcb to allow the lead to go through or just fit on the underside space permiting.
Virtually any npn signal transistor of appropriate rating will work OK... assuming there is no underlying fault that causes this part to fail.
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or temporarily fit a full size part if space allows, perhaps drilling the pcb to allow the lead to go through or just fit on the underside space permiting.
Virtually any npn signal transistor of appropriate rating will work OK... assuming there is no underlying fault that causes this part to fail.
It sounds like Q16 has failed, however it is possible that it is being pulled low by a faulty regulator. The two regulators that run from this supply are Z5 and Z11 if neither of these are hot to the touch then the problem is almost certainly Q16 and it is probably worth the effort of changing it.
Regards,
Andrew
In reply to Mr Moolys obvious attempt to imply I have some culpability for this problem, that is not really fair since I was not part of the service department and this product was designed years before I joined. Since this could be any one a of a number of problems causing the power supply to fail what sort of service note do you think would be appropriate, the faulty component needs to be diagnosed and replaced this CD player must be at least 8 years old. There is a full service manual for this product. ARCAM are one of the most conciensious manufacturers I have worked for, so implying that they are somehow trying to get one over on their customers by not advertising to the whole world about the symptoms of clock loss is silly, they will send the service manual to just about anyone who asks for it unlike most companies and will even talk to you on the phone about how to fix old products and supply parts. You reacted badly to my first message and you have reacted even worse to this one, I am trying to help this person, there is no conspiracy of silence.
Regards,
Andrew
In reply to Mr Moolys obvious attempt to imply I have some culpability for this problem, that is not really fair since I was not part of the service department and this product was designed years before I joined. Since this could be any one a of a number of problems causing the power supply to fail what sort of service note do you think would be appropriate, the faulty component needs to be diagnosed and replaced this CD player must be at least 8 years old. There is a full service manual for this product. ARCAM are one of the most conciensious manufacturers I have worked for, so implying that they are somehow trying to get one over on their customers by not advertising to the whole world about the symptoms of clock loss is silly, they will send the service manual to just about anyone who asks for it unlike most companies and will even talk to you on the phone about how to fix old products and supply parts. You reacted badly to my first message and you have reacted even worse to this one, I am trying to help this person, there is no conspiracy of silence.
Hi all,
16volts base, 2 volts emmiter means it is open circuit. It's not physically possible to have that polarity of volt drop across an intact n.p.n base emmiter junction.
Andrew... I'm sorry if I have upset you, I too am only trying to help. I have never worked on Arcam gear, but have a lifetime of experience in electronics, both design and repair. Manufacturers often issue updates, technical mods etc as faults come to light, often with mods to prevent a recurrence... it's common practice.
16volts base, 2 volts emmiter means it is open circuit. It's not physically possible to have that polarity of volt drop across an intact n.p.n base emmiter junction.
Andrew... I'm sorry if I have upset you, I too am only trying to help. I have never worked on Arcam gear, but have a lifetime of experience in electronics, both design and repair. Manufacturers often issue updates, technical mods etc as faults come to light, often with mods to prevent a recurrence... it's common practice.
Hi All, I would like to thank you all for your help, but I think it is only fair to say that Andrew understood what I was trying to say and pointed me straight in the right direction, even explaining what happens where and why. I think you should both kiss and make up. Now then, the 2v was on the emiter so I suppose the easiest step would be to fit another part and see if this cures it. I could never solder anything that small, so can you recommend a suitable part number to use, I would be most grateful. Barry
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