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Sony PS-X65 platter - Please help me?

T

tikijason

New Member
Hi All,

I got this turntable (in beautiful condition and the fanciest TT I've ever owned) for a song because the previous owner said it was broken. Long story short, I've replaced every electrolytic capacitor in the thing, cleaned and lubed the tonearm and platter motor, and fixed various other issues it had. It's a GEM! But there is one problem I just can't seem to solve: the turntable motor doesn't always start again, once I've stopped it. It doesn't seem to matter if there is a record on the platter, or if the tonearm is up or down, or if the TT is warmed up or cold. Sometimes the platter starts, sometimes it doesn't. On the occasions that it does start again after being stopped, it takes about seven seconds to get up to the proper speed again (which is way too long). Every other function seems to work great.

I have the service manual and it's been very helpful. But I've spent about a week reading that manual, fixing the various problems it had, and my brain is tired. Can anyone suggest a direction I should look? I am comfortable with this service manual and am good at replacing components. I don't have an oscilloscope.

If I can get this last issue fixed, I get to screw the bottom panel back on and go cartridge shopping! Can some kind soul please help?

Thank you in advance,
Jason
 
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Platter need a lube job? Does it spin freely when you give it a spin by hand, or does it fell like there is some resistance? I guess I don't know, but guessing its a belt drive? Even a DD table needs lube.
 
The PS-X65 is a direct drive. Since you replaced all the caps, it isn’t likely a motor startup cap, if there is such a thing. My first though (not a good thought) is one of the motor windings is shorted or open. A quick check to confirm is if it won’t start, and you move the platter a quarter or a half turn and then it starts, most likely a winding. Another thing you could look at are bad solder joints.
 
Thank you both for taking the time to read and respond!

WaynerN: I have disassembled the motor and oiled the spindle well. It spins freely and the quartz clock does not nave any problems maintaining a consistent speed once it is up to speed.

BilboBaggins: That’s a great diagnostic idea, and giving it a little push does seem to help sometimes. My thinking, though, is that unless I had to do that every time I want the platter to start turning, which I don’t, then it’s not likely to be the motor itself (?) Wouldn’t bad windings make the motor *never* start properly, instead of causing the intermittent problem I’m having? I was initially thinking more along the lines of this being a component somewhere in the startup function. My guess is that some component is failing to give the motor the proper voltage or current when I press that “start” button. But I’m not sure where to verify that. And do you mean I should check for bad solder joints in any particular places?

Thanks to you both!
 
tikijason said:
Thank you both for taking the time to read and respond!

WaynerN: I have disassembled the motor and oiled the spindle well. It spins freely and the quartz clock does not nave any problems maintaining a consistent speed once it is up to speed.

BilboBaggins: That’s a great diagnostic idea, and giving it a little push does seem to help sometimes. My thinking, though, is that unless I had to do that every time I want the platter to start turning, which I don’t, then it’s not likely to be the motor itself (?) Wouldn’t bad windings make the motor *never* start properly, instead of causing the intermittent problem I’m having? I was initially thinking more along the lines of this being a component somewhere in the startup function. My guess is that some component is failing to give the motor the proper voltage or current when I press that “start” button. But I’m not sure where to verify that. And do you mean I should check for bad solder joints in any particular places?

Thanks to you both!
Click to expand...

Electric motors can have many windings. Each winding covers one area on the rotor. So you could have one winding open or shorted and it is only a problem if the motor stops at that point. By moving it, you are checking to see if the motor is able to start at another location of the windings without any other change. Do not push it to start though. Just move it to a different spot. And then start from a stopped position.

Another way to check is to disconnect one lead on the motor, hook it to a dvm, and while measuring resistance across the motor leads, slowly move the platter around. You should see the resistance be stable, then up to open, then back down to the earlier measured resistance. And this should go back and forth as you rotate the platter. If you have an odd number of areas where there is a measurable resistance, then you probably have a bad winding. But this is bad news, as I don’t think anyone fixes these.

If it is a component, most likely the motor startup capacitor, if there is one. I didn’t have one in my PS-X600. So check the polarity of all the caps you changed to make sure you didn’t reverse one. Cold solder joints are not shiny. Try putting a dab of hot solder on each of those. It should cause the solder to flow and you should have a better connection. Leave the iron on each joint when adding the dab for about 1/2 second. Could also be a transistor that supplies power to the motor. So the area to check would be around the motor control board, if there is one.

These are just thoughts on where I would start. There is likely someone here who can help more than this. You could also try a google search on sony turntable that intermittently won’t start. Chances are someone else has run into the same problem somewhere.
 
BilboBaggins said:
Electric motors can have many windings. Each winding covers one area on the rotor. So you could have one winding open or shorted and it is only a problem if the motor stops at that point. By moving it, you are checking to see if the motor is able to start at another location of the windings without any other change. Do not push it to start though. Just move it to a different spot. And then start from a stopped position.

Another way to check is to disconnect one lead on the motor, hook it to a dvm, and while measuring resistance across the motor leads, slowly move the platter around. You should see the resistance be stable, then up to open, then back down to the earlier measured resistance. And this should go back and forth as you rotate the platter. If you have an odd number of areas where there is a measurable resistance, then you probably have a bad winding. But this is bad news, as I don’t think anyone fixes these.

If it is a component, most likely the motor startup capacitor, if there is one. I didn’t have one in my PS-X600. So check the polarity of all the caps you changed to make sure you didn’t reverse one. Cold solder joints are not shiny. Try putting a dab of hot solder on each of those. It should cause the solder to flow and you should have a better connection. Leave the iron on each joint when adding the dab for about 1/2 second. Could also be a transistor that supplies power to the motor. So the area to check would be around the motor control board, if there is one.

These are just thoughts on where I would start. There is likely someone here who can help more than this. You could also try a google search on sony turntable that intermittently won’t start. Chances are someone else has run into the same problem somewhere.
Click to expand...

Thanks again, BilboBaggins!

I disassembled the platter motor today, looking for bad solder joints. I didn’t find any, but I reflowed them like you recommended anyway. I also checked the platter motor windings for resistance and was getting 35-40 ohms across them all, which I believe is acceptable. That makes me think the motor is okay... is that a reasonable conclusion to draw, based on those tests? I also cleaned and lubed the shaft for good measure. It still acts the same.

I’ll replace the transistors I can verify are part of that circuit tomorrow, assuming I can find them in town. All the other solder joints look good to my eyes. I see no damaged PCB components. There isn’t a separate power supply board in this unit. I don’t see a capacitor specifically dedicated to starting the platter motor, but this problem existed both before and after the recap job I did. And I used high-quality Nichicon caps.

Two questions: does anyone here know which other Sony TT models may have used the same motor? I’m not above buying a “parts” motor online to substitute in. And what are these “evil VD1212 diodes” I keep reading should be replaced in most Sony TTS? I can’t see anything like that in my X65, but they have been named as a possible cause of this problem (and all others) in other boards I have read.

Thanks!
 
VD1212 diodes look like a small (<1/8" diameter) bead on a fine wire. Often red/green. If you find them, replace with a pair of 1N4148 or 1N4448 in series. I had a PS X65 but sold it a while back. I don't remember if it had VD1212 diodes. I seem to recall that it had capacitive touch buttons. One of mine failed. But I may be thinking of a different Sony table. It's a very nice table and worth while to get it repaired.
 
hirscwi said:
VD1212 diodes look like a small (<1/8" diameter) bead on a fine wire. Often red/green. If you find them, replace with a pair of 1N4148 or 1N4448 in series. I had a PS X65 but sold it a while back. I don't remember if it had VD1212 diodes. I seem to recall that it had capacitive touch buttons. One of mine failed. But I may be thinking of a different Sony table. It's a very nice table and worth while to get it repaired.
Click to expand...

Thank you for explaining that. I’m not seeing any inside my PS-X65. One thing I can now scratch off my list.
 
I am looking through the service manual and coming up with a list of transistors and a couple of ICs to replace, which would cost me about $60. I’m also looking for a replacement motor on
eBay. Several other similar Sony TTs of that era look like they used similar (maybe even identical) motors. The auctions where the motors are shown disassembled even seem to show identical windings to mine. Previous experience with radio transmitters makes me think there likely is no difference between motors of the same model line or era. I’m on the fence about which direction to go: continue replacing components, try a similar motor, or wait for a replacement motor to come up for auction? Any thoughts?
 
This table uses a printed magnetic track under the platter. Have you made sure that it's intact and clean (Don't wipe at it or use cleaners if it's dirty! Just inspect and report back, someone else will have to tell you if there is a way to clean it) and not demagnetized (get some magnetic viewing film and go around the platter track and look for flaws)?

There may also be an adjustment for the pickup height (looks like a tape head under the platter) that is incorrect. I know this is a common issue with the Denons that use a similar system. There should be adjustment instructions in the service manual if it is adjustable.

Other than that if it runs fine once started up but has a hard time starting, I wonder if there's a bad hall effect sensor or something is wrong with that system. Many of these use the hall effect sensors to figure out how to get the platter started and the magnetic track/frequency generator system to regulate the speed once everything is in sync.
 
EngineerNate said:
This table uses a printed magnetic track under the platter. Have you made sure that it's intact and clean (Don't wipe at it or use cleaners if it's dirty! Just inspect and report back, someone else will have to tell you if there is a way to clean it) and not demagnetized (get some magnetic viewing film and go around the platter track and look for flaws)?

There may also be an adjustment for the pickup height (looks like a tape head under the platter) that is incorrect. I know this is a common issue with the Denons that use a similar system. There should be adjustment instructions in the service manual if it is adjustable.

Other than that if it runs fine once started up but has a hard time starting, I wonder if there's a bad hall effect sensor or something is wrong with that system. Many of these use the hall effect sensors to figure out how to get the platter started and the magnetic track/frequency generator and system to regulate the speed once everything is in sync.
Click to expand...

Thanks EngineerNate,

I appreciate these ideas. There is a tiny hairline scratch, smaller than a cat hair, on the inside of the platter. However, based on the location of the scratch not seeming to be related positionally to the starting problem, I don't think it's the cause. I hadn't heard of magnetic viewing film, I'll keep that in mind. At this point, I have ordered a complete set of new transistors and a new IC107 and IC108. If that doesn't solve it, I'll replace the motor. I'm reluctant to adjust the magnetic pickup because it has glue on the screw heads. I'll advise what happens when the transistors arrive in week. I'd love more suggestions in the meantime.

If anybody has a PS-X65 or PS-X75 motor for sale, I'd love to hear from you.

Thanks, All.
 
Last edited:
Update: Transistors and ICs have arrived and I also saw this as a convenient excuse to buy a used oscilloscope. I should have this resolved by the weekend. I’ll update then. Thanks to all who have contributed to far.
 
New transistors and IC107 and IC108 installed. Inconsistent/slow motor startup issue persists. I’m thinking I’ll replace the motor next. I’ll advise then. It may take me a while to track down a replacement motor.

Thanks again to everyone who has helped so far.
 
I purchased a replacement platter motor, horizontal tonearm sensor, and main PCB online yesterday. The platter motor is what I expect to fix the issue; I ordered the other parts for spares only. Will update when it’s installed.
 
If you now have an oscilloscope, would it not be better to go through the service manual and check/adjust all your voltages and waveforms first? I don't mean to discourage you, but randomly replacing parts inside a unit like this on the offchance that they are faulty is not really the best way to approach things.
 
Hi Beobloke,

No offense taken. Your point is well-made. I'm still learning to use the scope but the things I have been able to check with it so far have come back pretty normal. Since the motor was one of the first suggestions to be replaced, and I finally found one, that'll be next. The other parts are intended to be spares for future repairs or other units. Great point, though. Thank you for your idea.
 
Well, everybody: I replaced the platter motor, as had earlier been recommended. It made no difference at all. The platter still starts and stops slowly, starts intermittently; and I’m out of ideas. At this point I’ve done a complete recap as well. I replaced the platter motor IC and the damn thing started spinning in reverse - It was installed correctly, too. I put the old IC back in and am still at square one. I’ll have to get better with this oscilloscope and keep trying and checking things.
 
Got it fixed. I had found a complete replacement circuit board and finally dropped it in. Problem solved. This surprises me because I had already performed a complete recap and replaced almost all transistors on the old board. Thank you to all who helped!
 
Hi DCH,

That X600 is a beautiful table! Enjoy it while it lasts and repair it when it breaks down. I don't know if you have any electronics repair skills, but I find myself getting possibly more satisfaction out of (and spending more time on) making repairs, than even listening to my records! But that's just me. Have fun!
 
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