Technics SL-10 Intermittent cueing problem


Hello, I am the sole owner of a Technics SL-10 turntable that I purchased back in the 80's when I was stationed in Germany with the US Army. The turntable still operates but has come up with a cueing problem that is intermittent that happens with regularity.  When the play button is activated the stylus cues as it should, the LP starts playing then it stops playing - the stylus lifts off the LP and returns to its detent position.  This same problem occurs at various points throughout the playing time of the LP.  Infrequently, the turntable operates as it should and plays just fine through the entire side of LP.  I took it to Los Angeles for repair by an outfit that has expertise with this particular turntable but I'm not confident that the technician can find and fix the problem.  I picked it up from this shop 2 weeks ago with a $400 bill that showed that a belt had been replaced along with a few other adjustments but it is still doing the same thing.  I took it back and the technician is ordering another belt from Japan - supposedly, the one designed for this turntable.  He used a makeshift one initially.  To me, the problem sounds more like a faulty sensor and may be out of the scope of this technician's expertise to fix.  There is an outfit in Canada that specializes in the repair of the SL-10  and I may end up having to ship it there but I was hoping that anyone on this forum may have some suggestions/recommendations of what the underlying problem may be.  Thank you, claviles
claviles
Its not the belt. Although it takes some nerve to charge $400 and use the wrong belt. And still not fix anything. So at the very least you have to admire their dedication to overcharging. But you’re right. I don’t know this particular model but they do use some kind of sensor to trigger the lift and return. Probably a photocell, when the arm breaks the beam it triggers. After 40 years its dirty, less light gets through, its gone all SJW on you, now the least little thing and its triggered. ;)

Pull the platter, maybe the base or plinth, look around, see what you can find.
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Here's a repair video that that shows/explains how the deck functions.

https://www.youtube.com/watch?v=f86WA63vEVs

Didn't watch the whole vid to see if he mentions the switch activated/deactivated by lowering/raising the lid, but that's another thing that can cause what you are experiencing.

DeKay

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Sorry to hear that.

The deck has Two belts which are used to move the tonearm on the rods via an offset gear mechanism.

Aside from checking the cover/lid switch (which can wear down and/or get gunk'd up) they should have cleaned and re-greased the gear mechanism as well as cleaned and re-lubed the Two rods that the tonearm slides on (new proper belts as well).

A dry Teflon based lubricant is used on the rods.

There are a few other adjustments (like tonearm start position) which take but a minute or Two.

As you can see from the above linked video it should be fairly quick/simple work.

DeKay


Hello again - I finally received the correct tonearm belt  from Japan and the intermittent lifting of the tonearm during play has been solved. Now my problem seems to be the replacement cartridge.  What is mounted is the AT312TP and the fidelity is compromised.  What is especially annoying is the distortion heard in between tracks; a low rumbling sound.  Can anyone suggest a better cartridge replacement?  On eBay, there's an AT33TP for sale. Is that compatible?