First direct drive project, maintence for a PS LX410?

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Big B5515
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Joined: 04 Nov 2012 01:27
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First direct drive project, maintence for a PS LX410?

Post by Big B5515 » 11 Oct 2019 03:53

I had been postponing this turntable project since spring, but as I finally sprung for a nice new cartridge today, I thought I would work on getting it ready to put to use. While it appears lightly used, and did not seem to have any issues when I tested it, I was thinking that after 35 years, it might be due for some preventative maintenance. I had looked at the service manual, and noticed that it calls for lubricant OL-2KA for the motor, which it appears must be disassembled to access circuit board from diagram (I have yet to actually get into it). I have no idea what else should be addressed, aside from common mechanical stuff, however thinking capacitors might become an issue, I already asked Coffee Phil, who didn't see one causing a chip failure, but did think servicing power supply might be worth while to prevent transformer failure. I wanted to ask if anyone familiar with these units knows a source, or good substitute for the lubricant, and if there is anything else I should check, or replace before putting this turntable back to use.
Service manual https://www.vinylengine.com/ve_download ... ice_en.pdf

Big B5515
long player
long player
Posts: 1814
Joined: 04 Nov 2012 01:27
Location: West Virginia

Re: First direct drive project, maintence for a PS LX410?

Post by Big B5515 » 20 Oct 2019 19:07

As searching online showed little info about this turntable, or the mystery Sony oil, I finally just referred to advice for another Sony unit with a motor fitting this one's description, and cleaned shaft, ball, and bearing sleeve with acohol, then used some suitable non detergent machine oil, SAE 20 electric motor oil in this case. While I would have liked to have known what oil had lasted 35 years, the motor now turns a bit more freely, but being this is my first older direct drive turntable, I'm guessing the magnet prevents platter from spinning completely free like I would expect, it still stops within about 6 or so revolutions. Turned out I had every electrolytic capacitor value in my parts box for this unit, except the 2- 1000uf filters which I still need to order, so as they were now over 2- 4 years old, went ahead and put eight of them to use anyway while oiling motor, before they become degraded from sitting on the shelf unused. While I have used capacitors that were 10 years old, or more in the past without issue, I had read that they don't have infinite shelf life, and ESR will increase with age. A more through examination of this unit showed cleverly disguised plastic on tonearm, and other shortcomings in quality, but as it does have halfway decent specs, .025% W&F and convenient, if limited adjustment of VTF & antiskating from 1-1.5 gm, I still hope to keep it going for a while longer. One other issue that seems somewhat common on turntables of this era was the small platter driven plastic gear for automatic functions shrinking and developing a crack. My repair was to carefully file out the center of gear preserving the ridge which locks it in place until it fit on platter with the crack completely closed, then remove from platter, clamp crack closed, and bury a piece of wire in epoxy glue in the groove on topside of gear to reinforce. The procedure for calibrating the 4 pots on circuit board sounds a little involved, and called for connecting a 2v DC from a variable power supply of which currently lack, so I opted to leave them undisturbed for now, and just see how it sounds first, the speed appears correct. Don't know why my last link to service manual won't work, but this one does.
https://www.vinylengine.com/library/Sony/ps-lx410.shtml

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