Sony PS-X7 speed problems
- Thread starter Blue Shadow
- Start date
restorer-john
Addicted Member
Excellent. Glad this thread has helped you. It's always nice when a brand new member posts comments like that. Take your time and be careful particularly if working on the arm/brake mechanism. They are tricky.
And by all means, ask any related questions in this thread. Cheers.
Blue Shadow
Waiting for Vintage Gear from this century
I got the PS-X5 to work properly sometimes and work right in Manual mode (auto return/shut-off). Since these tables are worth the work as I stated a few years ago, I'm gonna post some more info in this thread. First is a link to changing the neon strobe bulb after there are still troubles with it even though that 2.2µF/250V cap has been changed. BRB with that link.
OK,here is it: https://audiokarma.org/forums/index.php?threads/neon-strobe-lamp-supplier.900157/
OK,here is it: https://audiokarma.org/forums/index.php?threads/neon-strobe-lamp-supplier.900157/
Blue Shadow
Waiting for Vintage Gear from this century
Next, let's get the basics sorted out. I put this doc together from info on AK and especially Dave Shoaf (dshoaf) who has passed. It is a word doc on my machine and I'm not going to edit it to put it here:
Sony PS-X7 Dos and Don’ts
Arm mass is 14 grams based on @ETI_5000's quote of a british magazine test.
* Shipping: Make sure that the 4 feet are screwed in completely before the unit is shipped. The threaded shafts are easily broken if they are not threaded in and the packaging is not well done. Also, have the seller ship the platter removed from the spindle. I guarantee that it will migrate and damage something in shipment. I believe there's an FAQ for TT shipping. Have the seller read-and-heed. Install the shipping screws under the platter. They hold the transformer in place. The screws have a parking place under the platter to keep them until the table is moved again.
* Signal Cables: Be prepared to replace the cables as they are quite old now and weren't all that great to begin with. You don't have to go with high-cost wires but the connectors themselves aren't up to today’s quality, IMHO. This is pretty easy to do since the wires are soldered onto a small circuit board under the TT once you remove the lower cover - after having removed the feet. Remove two feet and lower cover. Then the cover for the tonearm wires. Replace tonearm wires. Red-Right Hot, Green-Right Ground, White-Left Hot, Blue-Left Ground.
* Wire-wrapped connections: There are *lots* of wire-wrapped connections on the circuit boards. Like many other 70s vintage gear, this was a popular technique for manufacturing in those days but, after the years, they may cause intermittent problems due to corrosion/oxidation of the metals. I generally go in and solder each one to be sure for this reason. This has not been done.
* Tonearm: A couple of don'ts - 1) do not attempt to disassemble the tone arm. I've not been successful getting back right. You can, however, remove the entire tonearm assembly en-masse but don't try to take apart the gimble, for instance. 2) you can potentially get a bit more performance out of the arm by working with a tracking LP or alignment record and adjusting the cartridge head. There are a couple of small screws that hold the cartridge head into the arm. They're underneath the arm tube. I discovered this when I worked as a bench tech in the 70s when I got a Shure cartridge analyzer. Turns out that most TT vendors didn't really pay attention to adjusting the plug-in heads. This would be an azimuth adjustment, the verticality of the stylus in the groove.
* Platter: Do not wipe out the lower rim of the platter. This carries a magnetic strip that is used to determine platter speed and drives the 'quartz' (marketing-speak for a crystal) locked speed control. You can clean it up but don't use much beyond a clean cotton cloth on it. Also, make sure that the pickup head, located in a small well on the plinth, isn't full of dust, which will impede its ability to pick up the magnetic pulses. There's an adjustment for it but it takes a scope or meter to do it.
* Speed: There are speed adjustments underneath on the speed control board. You do need the service manual, however, to do the setup. If it works, leave it alone. There are at least two types of speed problems where the table will sound bad. A consistent short term error in the speed a few times a revolution. This was cured by cleaning the speed pot on the board under the table. The other, an inconsistent stutter in the speed. This might have been cured by cleaning but appeared to be solved by recapping the unit. Finally, David mentions the need for accurate voltages for these circuits.
* Strobe: There isn't a replacement strobe bulb available anymore, this one a 150V 10mA is high power the NE series is about 1mA. Maybe an NE bulb will work with a high enough resistor to make it last in the circuit or there is an LED workaround but this won't light the strobe as well as the original bulb. If the strobe flickers, it might be cured by replacing the 2.2µF 250V cap in that circuit.
* Feet: Beware of the feet: The plastic shafts will crack, as they are hollow. They are unobtanium unless you've got a parts unit or pay on the bay. Here's what to do to help them out:
- Get a small nail about the size of the hollow shaft's hole. Make sure its a
long one to go all the way down to the foot itself and fills the whole hole.
- Use epoxy glue to make it stay. This retrofit has been done.
- Never over tighten the feet if you screw them down.
* The return mechanism is a light and photo eye that gets interrupted when the arm needs to be returned to its rest. Make sure the metal shutter is clean.
* Touch Switches: These can be removed and polished to make them respond to touch better so one doesn't need to wet their fingers first.
* Plastic: A lot of the underside of the table is plastic from the record size selector actuating arm on the switch to the ring for the automatic arm location lever on the tonearm. These are held in place with set screws. If the plastic cracks, additional grub screws can hold the size selector together and a wire tie wrapped around the lever below the set screws and glued in place can be used to bring life back to these features. If the size selector piece isn't broken a reinforcing coat of glue and something to add structure may keep it from breaking.
Loss of automatic feature repair:
But basically, as long as you have the original parts, the repair is easy. The hard part is finding a screw of the right size. I robbed one from an old CD-ROM from my computer that went kaput. Going by memory, the screw is about 1/4" long. Simply drill a small pilot hole where the little shaft busted off, run the screw through the hole, and place the spring, washer, and rubber bumper back over the screw.
There is a part that must be lubricated or it will break.. It's called a return cam, the number is
4-847-024-00 in the ps-x6-x7 manual. I managed to fix mine by drilling out where the little nub broke off and replacing it with a screw.
I might read this in a day or two and see if there is more info that needs to be added or if some needs to be removed.
Sony PS-X7 Dos and Don’ts
Arm mass is 14 grams based on @ETI_5000's quote of a british magazine test.
* Shipping: Make sure that the 4 feet are screwed in completely before the unit is shipped. The threaded shafts are easily broken if they are not threaded in and the packaging is not well done. Also, have the seller ship the platter removed from the spindle. I guarantee that it will migrate and damage something in shipment. I believe there's an FAQ for TT shipping. Have the seller read-and-heed. Install the shipping screws under the platter. They hold the transformer in place. The screws have a parking place under the platter to keep them until the table is moved again.
* Signal Cables: Be prepared to replace the cables as they are quite old now and weren't all that great to begin with. You don't have to go with high-cost wires but the connectors themselves aren't up to today’s quality, IMHO. This is pretty easy to do since the wires are soldered onto a small circuit board under the TT once you remove the lower cover - after having removed the feet. Remove two feet and lower cover. Then the cover for the tonearm wires. Replace tonearm wires. Red-Right Hot, Green-Right Ground, White-Left Hot, Blue-Left Ground.
* Wire-wrapped connections: There are *lots* of wire-wrapped connections on the circuit boards. Like many other 70s vintage gear, this was a popular technique for manufacturing in those days but, after the years, they may cause intermittent problems due to corrosion/oxidation of the metals. I generally go in and solder each one to be sure for this reason. This has not been done.
* Tonearm: A couple of don'ts - 1) do not attempt to disassemble the tone arm. I've not been successful getting back right. You can, however, remove the entire tonearm assembly en-masse but don't try to take apart the gimble, for instance. 2) you can potentially get a bit more performance out of the arm by working with a tracking LP or alignment record and adjusting the cartridge head. There are a couple of small screws that hold the cartridge head into the arm. They're underneath the arm tube. I discovered this when I worked as a bench tech in the 70s when I got a Shure cartridge analyzer. Turns out that most TT vendors didn't really pay attention to adjusting the plug-in heads. This would be an azimuth adjustment, the verticality of the stylus in the groove.
* Platter: Do not wipe out the lower rim of the platter. This carries a magnetic strip that is used to determine platter speed and drives the 'quartz' (marketing-speak for a crystal) locked speed control. You can clean it up but don't use much beyond a clean cotton cloth on it. Also, make sure that the pickup head, located in a small well on the plinth, isn't full of dust, which will impede its ability to pick up the magnetic pulses. There's an adjustment for it but it takes a scope or meter to do it.
* Speed: There are speed adjustments underneath on the speed control board. You do need the service manual, however, to do the setup. If it works, leave it alone. There are at least two types of speed problems where the table will sound bad. A consistent short term error in the speed a few times a revolution. This was cured by cleaning the speed pot on the board under the table. The other, an inconsistent stutter in the speed. This might have been cured by cleaning but appeared to be solved by recapping the unit. Finally, David mentions the need for accurate voltages for these circuits.
* Strobe: There isn't a replacement strobe bulb available anymore, this one a 150V 10mA is high power the NE series is about 1mA. Maybe an NE bulb will work with a high enough resistor to make it last in the circuit or there is an LED workaround but this won't light the strobe as well as the original bulb. If the strobe flickers, it might be cured by replacing the 2.2µF 250V cap in that circuit.
* Feet: Beware of the feet: The plastic shafts will crack, as they are hollow. They are unobtanium unless you've got a parts unit or pay on the bay. Here's what to do to help them out:
- Get a small nail about the size of the hollow shaft's hole. Make sure its a
long one to go all the way down to the foot itself and fills the whole hole.
- Use epoxy glue to make it stay. This retrofit has been done.
- Never over tighten the feet if you screw them down.
* The return mechanism is a light and photo eye that gets interrupted when the arm needs to be returned to its rest. Make sure the metal shutter is clean.
* Touch Switches: These can be removed and polished to make them respond to touch better so one doesn't need to wet their fingers first.
* Plastic: A lot of the underside of the table is plastic from the record size selector actuating arm on the switch to the ring for the automatic arm location lever on the tonearm. These are held in place with set screws. If the plastic cracks, additional grub screws can hold the size selector together and a wire tie wrapped around the lever below the set screws and glued in place can be used to bring life back to these features. If the size selector piece isn't broken a reinforcing coat of glue and something to add structure may keep it from breaking.
Loss of automatic feature repair:
But basically, as long as you have the original parts, the repair is easy. The hard part is finding a screw of the right size. I robbed one from an old CD-ROM from my computer that went kaput. Going by memory, the screw is about 1/4" long. Simply drill a small pilot hole where the little shaft busted off, run the screw through the hole, and place the spring, washer, and rubber bumper back over the screw.
There is a part that must be lubricated or it will break.. It's called a return cam, the number is
4-847-024-00 in the ps-x6-x7 manual. I managed to fix mine by drilling out where the little nub broke off and replacing it with a screw.
I might read this in a day or two and see if there is more info that needs to be added or if some needs to be removed.
Last edited:
Blue Shadow
Waiting for Vintage Gear from this century
Blue Shadow
Waiting for Vintage Gear from this century
Does the repeat function? I haven't been in the switches to see if the LED is easily replaced. One would think so but would need to see that board to verify the led is separate from the contacts and replaceable.
If you unit is not repeating then the touch switch is not putting the unit into repeat mode.
restorer-john
Addicted Member
If the repeat function is working and toggling between repeat and non-repeat, then it's just the LED failing. The deck is from 1976/7 or so and LEDs did not last forever, they were low output and often did lose their function.
That said, if the repeat is not actually working, you need to look at the amplifier (Q413/4) up front of the capacitive switch and the repeat flip-flop (Q415/6). Check the electros and the reset Q421:
That said, if the repeat is not actually working, you need to look at the amplifier (Q413/4) up front of the capacitive switch and the repeat flip-flop (Q415/6). Check the electros and the reset Q421:
Hi, after checking, it is the repeat function that does not work. Hmmm, more fun and games.
Just want to say thanks to Blue Shadow and r-John for your comments/feedback/help. If we can get the strobe and repeat functioning, I think she'll be 100%. Cheers
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Chiwahua
New Member
Hey guys,
I thought I'd share my PS-X6 speed issue in this thread.
The speed on my turntable just keeps changing. See the speed graph I attached. It just keeps oscillating.
I believe I need to clean the VR201... Am I right?
The oscillating part is puzzling me, it seems so regular...
Thanks A LOT for your help!
Thanks
I thought I'd share my PS-X6 speed issue in this thread.
The speed on my turntable just keeps changing. See the speed graph I attached. It just keeps oscillating.
I believe I need to clean the VR201... Am I right?
The oscillating part is puzzling me, it seems so regular...
Thanks A LOT for your help!
Thanks
Attachments
Chiwahua
New Member
I needed to adjust VR201. Before doing so, I made sure that I had 14 VDC at VR101 (see adjustment section in service manual).
To everyone with PS-X6 or PS-X7 with speed issues, try to readjust VR 201. It could either be off (strobe moving either sides) or speed oscillating. It could also be affecting speed 45 alone or 33&45.. I think you have some range of adjustment on pot where both speeds strobe is stable. Very easy to fix. Maybe a bit of contact cleaner for potentiometer would help!
I didn't even have to disconnect white wire like thr procedure said in service manual. I don't know why I would need to disconnect the white wire if just turning the Vr201 seemed to solve the issue.. (Someone knows?)
To everyone with PS-X6 or PS-X7 with speed issues, try to readjust VR 201. It could either be off (strobe moving either sides) or speed oscillating. It could also be affecting speed 45 alone or 33&45.. I think you have some range of adjustment on pot where both speeds strobe is stable. Very easy to fix. Maybe a bit of contact cleaner for potentiometer would help!
I didn't even have to disconnect white wire like thr procedure said in service manual. I don't know why I would need to disconnect the white wire if just turning the Vr201 seemed to solve the issue.. (Someone knows?)
Blue Shadow
Waiting for Vintage Gear from this century
reads like you have fixed the problem. Nice to have another one of these great TTs back in business.
Chiwahua
New Member
Yes indeed it fixed the problem. I still don't know if I missed something by adjusting RV201 without removing the white cable though... I could see directly the effect on the speed adjustment when it was in a range where the speed is locked for both 33 and 45.
Do you guys know why the procedure tells to remove this white wire before adjusting?
Do you guys know why the procedure tells to remove this white wire before adjusting?
Fasturd
Active Member
Love AK and it's members!
Brought a new to me PS-X7 home today. It had a few quirks that are now solved thanks to this thread.
I need to figure out what cart and stylus to run. It came with an ADC. Which seems a bit low class in this application. I have a spare Stanton and a Shure V15 or two to play with.
Anyone have a successful combination they would like to share?
TIA.
Brought a new to me PS-X7 home today. It had a few quirks that are now solved thanks to this thread.
I need to figure out what cart and stylus to run. It came with an ADC. Which seems a bit low class in this application. I have a spare Stanton and a Shure V15 or two to play with.
Anyone have a successful combination they would like to share?
TIA.
Attachments
Blue Shadow
Waiting for Vintage Gear from this century
Denon DL-160 sounds very nice on the PS-X7 I haven't returned to my brother, yet. He needs to commit to setting up the stereo. Smoother, cleaner than the M91ED that had a near new stock stylus on it.
MX117.MC7150
Listener
Warms the cockles of my heart that youse guys are getting all these PS-X7 TTs 'running right' these days. Absolutely my favorite auto-TT from Sony and I used one from its first year of production until I sold to a friend in 1995 who still uses it (in manual mode as all the auto functions died). I've offered to have it repaired for her, but she is happy with it 'as is' and said she doesn't want it gone for the time it would take to repair. Keep up the good work. 
@restorer-john @Blue Shadow Hello again! Wanted to provide an update on my progress. Its been a slow and steady go of it, but im nearing the end. Here's a progress shot:
Its interesting because I did have the issue where post was broken off from the return cam. I found a badly treated unit on the "bay" so I harvested that and a few misc parts to make the repair. I still have the broken part and I have been considering getting into 3D modeling and designing a replacement. Still on the fence about that one.
I actually replicated the "wrap" technique for the wiring and it turned out really well. I do know if issues creep up to start there and check all connections. I was wondering if anyone found any caps that could be soldered to the wire and slipped over the poles? I've been poking around but havent found anything yet that I like.
Getting the stylus drop point set correctly took me hours to figure out, so if any needs help with that adjustment/setup please let me know.
I'm at the point were most everything works save for auto return from either pressing stop, or reaching the end of the record. My first step is to now check "The return mechanism is a light and photo eye that gets interrupted when the arm needs to be returned to its rest. Make sure the metal shutter is clean." I should mention that the tone arm lifts when the stop is triggered, it just doesn’t move to the home position. Any other thoughts on a fix are very appreciated.
In case anyone is wondering, the lego thing in the photo is a stand I built to hold the unit upside down so it didnt slide around or fall. I have to say it worked really great!
Lastly here's a video of the unit functioning, and I really cant wait for it to be 100% done!
https://i.imgur.com/jcgg8Yc.mp4
edit: more and clarifying info
Its interesting because I did have the issue where post was broken off from the return cam. I found a badly treated unit on the "bay" so I harvested that and a few misc parts to make the repair. I still have the broken part and I have been considering getting into 3D modeling and designing a replacement. Still on the fence about that one.
I actually replicated the "wrap" technique for the wiring and it turned out really well. I do know if issues creep up to start there and check all connections. I was wondering if anyone found any caps that could be soldered to the wire and slipped over the poles? I've been poking around but havent found anything yet that I like.
Getting the stylus drop point set correctly took me hours to figure out, so if any needs help with that adjustment/setup please let me know.
I'm at the point were most everything works save for auto return from either pressing stop, or reaching the end of the record. My first step is to now check "The return mechanism is a light and photo eye that gets interrupted when the arm needs to be returned to its rest. Make sure the metal shutter is clean." I should mention that the tone arm lifts when the stop is triggered, it just doesn’t move to the home position. Any other thoughts on a fix are very appreciated.
In case anyone is wondering, the lego thing in the photo is a stand I built to hold the unit upside down so it didnt slide around or fall. I have to say it worked really great!
Lastly here's a video of the unit functioning, and I really cant wait for it to be 100% done!
https://i.imgur.com/jcgg8Yc.mp4
edit: more and clarifying info
Last edited:
Seriously thank you. Such a wealth of knowledge!!!
restorer-john
Addicted Member
Excellent news you got the Sony up and running again! 
The Lego stand in interesting.
I'll let you in on my secret turntable stands for working on upturned TTs. Toilet rolls, three or four of them. Soft, strong, easily moved around and positioned, don't tip over or damage the turntable's finish.
The Lego stand in interesting.
I'll let you in on my secret turntable stands for working on upturned TTs. Toilet rolls, three or four of them. Soft, strong, easily moved around and positioned, don't tip over or damage the turntable's finish.
MX117.MC7150
Listener
Good work and excellent thread.
There are a number of PS-X7 threads from days of yore, like this one from 10yr+, ago, that may add additional info on repairs, adjustments, etc.
https://audiokarma.org/forums/index.php?threads/sony-ps-x7-open-heart-surgery-successful.285717/
There are a number of PS-X7 threads from days of yore, like this one from 10yr+, ago, that may add additional info on repairs, adjustments, etc.
https://audiokarma.org/forums/index.php?threads/sony-ps-x7-open-heart-surgery-successful.285717/