Another one hopefully can be saved. Sony PS-X7

Blue Shadow

Waiting for Vintage Gear from this century
Picked one up. Not too expensive

No headshell
No hinges on the dust cover but the sockets are on the table
Bad speed on 33 rpm ok on 45 so I'm guessing the sensor ring on the platter is ok.
Maybe it needs adjustments, maybe caps.

Guess I need to be on the lookout for some parts while I do some cleaning and speed adjustments.
 
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I believe there are voltage adjustment pots under the bottom cover. Those need to be checked for proper voltage spec. Also, a recap of the power supply is likely in order. Lastly, the auto-return mechanism is driven by a light and sensor system. Make sure it is ok, too. You really need to get a Service Manual for it.

They're wonderful tables - I remember taking the first one out of the box when it arrived at the store where I worked back in the 70s.

Cheers,

David
 
They're wonderful tables - I remember taking the first one out of the box when it arrived at the store where I worked back in the 70s.

Cheers,

David
My first one was like that. Not in a sealed box but in the box. It still had the plastic on the dust cover but needed work. I recapped that one and there was still a problem with the speed but cleaning the speed pot on the circuit board fixed it. That one also had some greasegloo keeping the auto function from working. Those repairs a recap and of course collecting your comments about the units weak points...feet for instance, has made that first one a nice table. But my brother asked for a turntable shortly after I got it so I never got much of a chance to enjoy it.
 
Getting back to this table after cleaning it last night and investigating the strobe (slow to light up) and after pulling the top cover finding one of the three mounting posts for the transformer broken. JBWeld fixed that but I needed to let it harden. Have seen a few of these PS-X tables and all of them had their two red screws mounted to the paper that explains where to use them to hold the transformer in place. On the two I have repaired, I drew lines to the the locations to use them to hold the transformer when the table is moved more than around the house. Unfortunately, I don't know anyone that doesn't ak that knows there are things under a platter that might need to be secured for transport. Fortunately, this wasn't a big deal on this table.

Good news is that it started properly move to the record size setting when started.
 
This table had a hitch in the 45 rpm and 33 was fast, a good bit fast. First attempt was a cleaning of the speed pot on the circuit board underneath. Hitch is gone but now 45 is a bit slow and 33 is a bit fast, but much closer to correct. Guess I need to hook up the scope and step through the complete speed set up procedure.

While I have the JBWeld out, I'll reinforce the feet, all 4 in good shape, no broken threaded studs on them. Hope to keep the feet that way.
 
Thanks for that link. Reading through it with the X4 and X6/7 SM open to see what happens. The first issue, the 14V source is correctly located on the X6/7 so I'm good on page one. I'll read the whole thread and see where you are with your tables. Maybe you even mention the rest of the Sony gear you mentioned.
 
Interesting repair, cleaning the speed switch. I don't like those types of slide switches but I'll be cleaning this one and maybe the other tables here since it has not been done to them and once I do one the others will be easy. Maybe the owners would come get their tables before I'm done. I'd be ok with that as the tables are working fine right now.

@Van_Isle the thread didn't tell us how you made out with your Sony gear.
 
Rebuild the power supply, and if there are any of those horrid VDxxxx series varactors in the motor drive system, change them out for a pair of diodes in series.
 
Switch is cleaned per the picture tutorial in the above link to VE. Take pics or you might put the switch back together upside down, this providing the 33 rpm speed in the 45 rpm position and vice versa. No big deal all squared away now. This PS-X7 did not have a copper piece for the speed push buttons to ride on. The piece is a different metal. A touch of lubriplate to give it another 35 years of smooth movement. All working fine on that front. Speed is a bit slow on 33 and a good pit fast on 45, need to do the electrical set up to see what happens.

Got the cap list from the manual and from the boards, the PS board under the cover below the platter and from the drive board on the bottom of the table. Well compare and put together a cap list.

Sourced a couple hinges and backing plates from the bay, the dust cover, needing a bit of work but no deep scratches, has the bracket parts on it so only needed the parts that mount on the turntable and the screws and such. I have an extra PS-X4,5,6,7 headshell so it will be close to correct. The 7 has a black headshell, the others are silver. Might need some paint!!!
 
...While I have the JBWeld out, I'll reinforce the feet, all 4 in good shape, no broken threaded studs on them. Hope to keep the feet that way.

Use a small nail to fit into the hollow shaft of those threaded feet. I used some epoxy to secure them in there. This adds a lot of strength to them. The problem, I believe, comes when someone tilts the turntable back or on its side with the feet extended. The shank cannot support the entire weight of the table.

Cheers,

David
 
I think you are correct about the mode of failure. I have already done two PS-X tables based on your recommendation. This table had the legs screwed all the way in and they were undamaged.
 
How about that, I had enough caps left over to recap the PS board, except the 2.2µF/250V cap for the neon strobe. I used a couple 1.0/250 film caps and will replace them with a nice Nichicon PW or HE or something when I order the caps for the speed control board.

Strobe light wakes up immediately, shines bright as it should.

Adjusting the voltage, no change from the 14.05 I dialed in previously. Close enough to the 14 spec. The speed was off so removed the white wire per the service manual and got 45 set but I'm not comfortable with everything else so will be recapping the control board, too. But we are getting closer.
 
Hinges for the dust cover, the part that mounts to the tt are in.
Owner's manual is in, thanks Marc Morin.

Turntable sidelined while I think about it some. Following the manual for setting the speed, the first step, remove the white wire and speed is corrected by the VR on the board. Worked fine. Replace the white wire and speed is wrong again and a hitch in the 45 develops.

Looking at the next step, apply 1.5VDC to the resistor just before the VR and measure 1.9VAC after the VR. This is a complete fail. I have no idea how a resistor and a VR are going to change DC voltage to AC and well we weren't getting anything good anyway.

Thinking about recapping the speed control board before going back to the electrical set up unless others have some input on this.

Curious if this unit would have bad NLA parts if both speeds do have platter movement kinda in the area where it should be?
 
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