My Shanling CD-T80 has started ticking on playback.
Resting finger on puck quietens it.
Should I replace the mechanism?
Do I just replace the spindle motor?
Also, from new the drawer has scraped when opening/closing.
It scrapes on the aluminium plate holding the puck.
The drawer has some vertical play that allows this; the guides do not hold it down, only prevent it from lifting off completely.
Gravity would appear to be what holds it down, perhaps the heavy aluminium drawer front works against this. Anyone come across this and have a fix?
The dealer did fix the drawer noise for a while - I suspect by raising the aluminium plate with some washers I have just found.
Resting finger on puck quietens it.
Should I replace the mechanism?
Do I just replace the spindle motor?
Also, from new the drawer has scraped when opening/closing.
It scrapes on the aluminium plate holding the puck.
The drawer has some vertical play that allows this; the guides do not hold it down, only prevent it from lifting off completely.
Gravity would appear to be what holds it down, perhaps the heavy aluminium drawer front works against this. Anyone come across this and have a fix?
The dealer did fix the drawer noise for a while - I suspect by raising the aluminium plate with some washers I have just found.
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Ticking can be the sound of the servo and focus motor drive coils and can associated with a scratch on the disc.
Changing the CDM12.1 I suspect isn't the answer. With a disc in tray as in your picture then the disc should be free to rotate and not scrape on anything. Platters have been known to shift, they are just a tight push fit with a dab of epoxy to hopefully secure them from moving lower down the motor shaft.
It's really one of those things you need in front of you but ticking doesn't sound like a pickup fault as such, its either mechanical fouling or the focus coil.
Make sure the disc runs true. There should be no detectable run out on the disc edge (yes it should be that good with a genuine original Philips part). Look at it edge on. If the disc wobbles up and down at the edge then the platter is out of true or there is debris on the platter.
Changing the CDM12.1 I suspect isn't the answer. With a disc in tray as in your picture then the disc should be free to rotate and not scrape on anything. Platters have been known to shift, they are just a tight push fit with a dab of epoxy to hopefully secure them from moving lower down the motor shaft.
It's really one of those things you need in front of you but ticking doesn't sound like a pickup fault as such, its either mechanical fouling or the focus coil.
Make sure the disc runs true. There should be no detectable run out on the disc edge (yes it should be that good with a genuine original Philips part). Look at it edge on. If the disc wobbles up and down at the edge then the platter is out of true or there is debris on the platter.
Checked disc edge with DTI.
Not easy as the pressure from the DTI is significant with such a delicate mechanism.
About 0.4mm runout both radially and up/down.
About 0.1mm up/down on the platter which is pro-rata for the smaller diameter.
I have got identical results with 2 different CDs.
I checked for debris.
Not easy as the pressure from the DTI is significant with such a delicate mechanism.
About 0.4mm runout both radially and up/down.
About 0.1mm up/down on the platter which is pro-rata for the smaller diameter.
I have got identical results with 2 different CDs.
I checked for debris.
A long time since I used a gauge... eccentricity adjustment on Betamax head disks actually 🙂
0.4mm doesn't sound brilliant tbh and if you play an outer track on the disc you will see the lens moving by that amount but I have seen worse and I don;t think that would account for any ticking sound.
It would be worth looking with a scope at the focus and tracking signals as applied to the coils and to see if the 'tick' you hear corresponds to a spike in the drive waveform. You need to pin down where the tick noise comes from first of all.
0.4mm doesn't sound brilliant tbh and if you play an outer track on the disc you will see the lens moving by that amount but I have seen worse and I don;t think that would account for any ticking sound.
It would be worth looking with a scope at the focus and tracking signals as applied to the coils and to see if the 'tick' you hear corresponds to a spike in the drive waveform. You need to pin down where the tick noise comes from first of all.
If it was caused by runout it would be quiet in centre of disc & noisy at periphery.
After all the messing it does seem to have quietened.
I think, after 15 years, everything is a bit dry.
A drop of oil from the end of a jeweler's screwdriver on the spindle seems to have silenced it completely.
The noisy drawer - seems to be by design. The drawer rubs the puck aluminium support bar.
Placing a strip of paper between silences it and proves the source. After 15 years it's beginning to annoy me. I might have to dream up a fix for it.
Thanks for the encouragement.
After all the messing it does seem to have quietened.
I think, after 15 years, everything is a bit dry.
A drop of oil from the end of a jeweler's screwdriver on the spindle seems to have silenced it completely.
The noisy drawer - seems to be by design. The drawer rubs the puck aluminium support bar.
Placing a strip of paper between silences it and proves the source. After 15 years it's beginning to annoy me. I might have to dream up a fix for it.
Thanks for the encouragement.