Brand new user, first time to post. Greetings to all and thank you for any help.
I joined due to the very informative thread here already on a Nak OMS-5 and I'm hoping anatech is still around and will chime in. Ok, the problem.
I bought a OMS-5 a couple weeks ago, brought it home plugged into the CA-5, a MC250 and an old set of speakers. It worked great and sounded even better! It loaded every CD I threw at it, new, old, burnt on every type of media and even scratched ones.
Concluding it worked well I moved it to my main system and plugged it into a Yamaha reviver, where is shared a powerbar/splitter with a pile of other electronics. It immediately developed an issue reading/loading CDs, any CD it doesn't matter the type. Once loaded it will play any of them fine, but it normally ejects them back out instead of loading.
Order of problem:
1) Plug in OMS-5, first CD loads perfectly. If you swap CDs at this point it will load as many as you want perfectly.
2) Play CD and stop somewhere along the way, say a few songs in.
3) Second CD will not load. I can hear laser tracking back and forth and then ejects out the CD.
4) If I continue to try CDs it will continue to eject them out.
5) If I turn off the OMS-5 and turn back on, this will sometimes fix the problem. Although turning off and unplugging seems to work better.
6) After powering down, the 1st CD I can hear the laser track one way and then the CD loads and laser returns. Load now a 2nd CD and the laser does not move at all, just loads CD (like #1 above).
I have now removed it from my main system and is plugged in by itself with nothing else attached and it still has this issue. Any suggestions?
I joined due to the very informative thread here already on a Nak OMS-5 and I'm hoping anatech is still around and will chime in. Ok, the problem.
I bought a OMS-5 a couple weeks ago, brought it home plugged into the CA-5, a MC250 and an old set of speakers. It worked great and sounded even better! It loaded every CD I threw at it, new, old, burnt on every type of media and even scratched ones.
Concluding it worked well I moved it to my main system and plugged it into a Yamaha reviver, where is shared a powerbar/splitter with a pile of other electronics. It immediately developed an issue reading/loading CDs, any CD it doesn't matter the type. Once loaded it will play any of them fine, but it normally ejects them back out instead of loading.
Order of problem:
1) Plug in OMS-5, first CD loads perfectly. If you swap CDs at this point it will load as many as you want perfectly.
2) Play CD and stop somewhere along the way, say a few songs in.
3) Second CD will not load. I can hear laser tracking back and forth and then ejects out the CD.
4) If I continue to try CDs it will continue to eject them out.
5) If I turn off the OMS-5 and turn back on, this will sometimes fix the problem. Although turning off and unplugging seems to work better.
6) After powering down, the 1st CD I can hear the laser track one way and then the CD loads and laser returns. Load now a 2nd CD and the laser does not move at all, just loads CD (like #1 above).
I have now removed it from my main system and is plugged in by itself with nothing else attached and it still has this issue. Any suggestions?
Hello Ed and welcome to diyAudio.
You'll probably have noticed if you have read any of my threads that I always recommend using an oscilloscope to see what is actually happening and to confirm the quality of the signal from the laser pickup.
I am not familiar with Nak and am not sure what mechanism and pickup it uses but I would definitely look at the "sled" the laser tracks along to make sure it is free. Some high quality machines used a linear motor rather than gears... but the same applies... it has to be free.
Also make sure any "limit" switches are clean (so that the system control gets the message the laser has reached the end stop
). And finally is the lens clean and bright ? Don't use glass cleaner (that has ammonia) but use a proper fluid... I never what to suggest here as I use proper Sony stuff, and Sony specifically warned against using ISO as that could damage coated optics... although many use it with no problems at all.
You'll probably have noticed if you have read any of my threads that I always recommend using an oscilloscope to see what is actually happening and to confirm the quality of the signal from the laser pickup.
I am not familiar with Nak and am not sure what mechanism and pickup it uses but I would definitely look at the "sled" the laser tracks along to make sure it is free. Some high quality machines used a linear motor rather than gears... but the same applies... it has to be free.
Also make sure any "limit" switches are clean (so that the system control gets the message the laser has reached the end stop
). And finally is the lens clean and bright ? Don't use glass cleaner (that has ammonia) but use a proper fluid... I never what to suggest here as I use proper Sony stuff, and Sony specifically warned against using ISO as that could damage coated optics... although many use it with no problems at all.Mooly, thanks for the reply.
When this problem first started, I opened the top and very carefully dusted the whole interior and wiped the lens (no fluids). Everything looked very clean and seemed free to move but will check again.
As for a scope, I can borrow one and will read up on what I should be looking for. I hope two lectures of EE in undergrad is enough for this project! Thanks again and I'm sure more questions to follow.
When this problem first started, I opened the top and very carefully dusted the whole interior and wiped the lens (no fluids). Everything looked very clean and seemed free to move but will check again.
As for a scope, I can borrow one and will read up on what I should be looking for. I hope two lectures of EE in undergrad is enough for this project! Thanks again and I'm sure more questions to follow.
Since it sounds like an otherwise healthy & well aligned OMS-5, you probably need to do two things to cure the current fault. 1)Pop the bottom panel & you will see, near the front corner of the unit, the tracking drive motor. It uses a small, flat belt, around the naked shaft of the motor. Clean the belt with isopropyl alcohol or MEK, then give the belt a one minute soak in natural turpentine, then blot dry & let air dry for a bit. Then re-install. 2)Clean & re-grease the laser sled guide rails, making sure to work the new grease(a light silicone or molybdenum grease) well into the sleeve bearings of the laser unit, by running the laser manually back & forth(while tracking belt is out). You most likely will have no more trouble.
IMPORTANT: A preventive measure to take on the unit is to remove the power supply board at the back end of the top side of the unit & resolder all voltage regulators & other suspect connections. These players almost always have cracked joints on this board that will randomly cause trouble.
IMPORTANT: A preventive measure to take on the unit is to remove the power supply board at the back end of the top side of the unit & resolder all voltage regulators & other suspect connections. These players almost always have cracked joints on this board that will randomly cause trouble.
Stephen, thanks for your help.
Greasing seems to be working. I opened the bottom, dusted and lightly greased the laser sled guides (they were totally dry to the touch). This fixed the problem for a couple hours and on the weekend when I could gather the correct solvents I cleaned the belt and more liberally greased the rails. It has been running for two days now and track seek time has been significantly reduced. Thank you very much!
Greasing seems to be working. I opened the bottom, dusted and lightly greased the laser sled guides (they were totally dry to the touch). This fixed the problem for a couple hours and on the weekend when I could gather the correct solvents I cleaned the belt and more liberally greased the rails. It has been running for two days now and track seek time has been significantly reduced. Thank you very much!
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