I recently acquired an example of the legendary Technics SL-10 turntable. Despite its non-working status, the price was such that I simply couldn’t refuse – and, having experience with linear tracking turntables of this nature, I was confident I could restore it to full working condition.
And that’s exactly what I did – in fact, the turntable is playing as I write and, with the original MC310 cartridge, it sounds nothing short of beautiful.
All this particular turntable required was the usual maintenance, as detailed in my post regarding Technics linear tracking turntable maintenance. However, getting the turntable apart was something of a task – and the lack of information in the service manual and on the internet resulted in a lot of trial and error. I have attempted to form the notes which I took at the time into something worthy of a blog post – which, hopefully, will serve to help others out there with this same turntable. Unfortunately I didn’t think to take any pictures at the time – but hopefully my descriptions will be good enough.
Removal of the upper cover.
The first, and arguably the most frustrating issue I encountered was the removal of the upper cover. The manual states that removal of the 12 setscrews should allow the cover to simply lift away, revealing the mechanism beneath. However, this was not the case – thanks to the small plastic snaps keeping the cover secure around the clamp area. These plastic clips hold the cover firmly in placed -and cannot be unclipped unless the transparent window is removed – which, ironically requires the upper cover be removed first. Still with me? OK.
The easiest, and least damaging way I found to remove the cover was to heat the area around the clamp to soften the plastic and allow it to come free. Once all 12 screws are removed, take a hair drier and heat the circular area situated to the right of the record clamp as you look at the turntable from the front. If, like me, you opened the turntable with it resting on its lid and the buttons facing you, the part you’re looking to heat is the part closest to you on the left, nearest the arm. You’ll know you’re heating the correct part as there is no gap between it and the dust cover window, whereas there is a significant gap on the other side.
Apply heat for around 30 seconds – be careful to get things warm but not too hot. Once heated, lift the cover from the sides, place a finger in the middle next to the arm rail, and lift up, twisting slightly to the left as you go. The cover, with the record clamp attached, should pop right off. You can also lift the cover by grasping the record clamp – as it is attached to the cover itself.
Once inside
Once inside, you’re greeted by a relatively standard iteration of the technics mechanism, all be it covered by a large circuit board. Removal of a single screw behind the arm motor allows that circuit board to be lifted from its resting place, allowing you to unplug its cables and tilt it up out of your way.
My particular turntable simply refused to move its arm. A few seconds of prodding at the mechanism revealed the arm motor was frozen solid. 2 Screws later, and said motor was removed. 3 Drops of bearing oil were dropped into the tiny gap underneath the spindle, and after turning it by hand for several minutes the motor was free and running like new.
All that remained was to clean and relubricate the mechanism, and replace the small square-section belt which runs the mechanism. Genuine replacement belts can be purchased very cheaply online, so it’s a good idea to replace this while you have the turntable open. I also dropped some grease around the clamp area and on the tonearm cable protection guide.
The only complication I ran into during reassembly involved the lid switch – mounted to the rear of the circuit board, this switch must be fully depressed to allow the upper cover to clear it. The end of the switch pokes out through a hole in the upper cover, and is pressed against the rear of the turntable when the lid is closed. As you’re slotting the upper cover into place, be sure to press in that switch with the aid of a small screwdriver – as failure to do so will render the turntable inoperable and cause you many hours of frustration.
After all this was complete, I had a fully functioning SL-10. I did also choose to replace the platter bearing oil – a simple matter of removing the platter and applying some cleaner and fresh oil to the gap beneath the spindle. The platter is removed by removing the plastic nut that holds the 45RPM adapter in place, and removing the nut and washer beneath. Be sure not to over tighten either nut during reassembly.
Hopefully this information has been of use to those of you attempting to restore these decks to working condition. Despite the problems getting this deck apart, I still maintain that Technics decks are some of the easiest to work on – and this would’ve been too if it weren’t for that record clamp.
Funny thing. I just acquired NEW OLD STOCK SL-10 that was never taken out of the box and had the same exact same issue. Weak point? Not really as the turntable was made some 40 years ago and still had grease on all its bearings. Build quality and efficiency of design of SL-10 is simply breathtaking even today or rather especially today.
Thank you for the write up, it helped a lot, particularly the trick with a heat gun. I have one question though, do you prefer your SL-10 with the puck or without it as many people say removing the puck makes the sound “more open”?
Greetings
Steven in Florida
Hi Steven. Very nice find, I can’t imagine there are many boxed SL-10s out there. Firstly, I’d recommend a hair drier rather than a heat gun, as most heat guns do not have a temperature control and heat to a minimum of 200 degrees C. That is enough to melt and deform the plastic cover. The record clamp is a part of the Technics design. The reason most people prefer it removed is because they don’t service the turntable properly. If you don’t lubricate the contact points in the clamp assembly with a suitable grease (PTFE ideally) you will hear increased rumble. As a result the deck will sound quieter and thus ‘more open’ with the clamp removed. An SL-10 serviced correctly won’t suffer this problem, so I would recommend leaving the clamp mechanism intact and service the deck properly.
Recently bought one online (advertised as working.) The first time I turned it on I immediately got a lot of droning mechanical noise coming from the lid and it only very, very unsteadily moved the tonearm to the middle of the platter – it had been moving back and forth along the track freely when I first opened it up. Since then nothing, tone arm isn’t budging from that position either in automatic or manual settings or powered down and I’m still getting that mechanical noise from the lid the whole time anytime it’s powered on. Any ideas what’s wrong or where to start troubleshooting? Pretty bummed
99% the rubber belt that drives the needle back and forth is gone. If the needle currently isn’t in rest position, the controller will try to bring it back as soon as powered on. Follow carefully the disassembly instructions on this or other websites (you can get a service manual at https://www.vinylengine.com/library/technics/sl-10.shtml (login needed) )
THe arm shouldn’t slide freely on the track, it sounds like it wasn’t packed properly when shipped. The arm should have been locked to the side, and something put in place to stop the rail sliding sideways. I’d imagine the belt will have failed, but in your case the drive rope has probably been damaged too – in which case you’ll need a parts unit. You might get lucky and find the drive rope has just come unclipped from the bottom of the arm carriage.
Not too happy to hear that even if I can get to the bottom of this I’ll probably need a whole other junk player (that hopefully hasn’t failed in the exact same way) to fix it but that’s life I guess. Thanks for the reply
My issue after a week of spinning vinyl on the SL-10 is that it is not sensing a 45rpm record and it’s not recognizing when there is no record at all. It must be the optical sensor, but does anyone have a clue what goes wrong with them? The red LED’s under the platter are glowing. Thanks!
Usually the photosensors in the lid are dirty, or the switches in the base need cleaning with an electrical contact cleaner. It could also be that the system is out of adjustment. These are 40 years old now, and electronic components do fail and drift in value as they age. The service manual is readily available and the adjustments can be made by any competent tech with the usual equipment (a voltmeter and oscilloscope). I would start by taking off the lid cover and checking the photosensors, as if it plays a 12 inch disc I doubt the circuit is failing completely.
Just bought an SL-10 is great shape (touch wood) with a Technics P23 cartridge. I was shocked upon first listen to hear quality that’s equal to my SL1200 mk2 with Reloop/Ortofon/KAB Concorde Black 40. This is a wonderful turntable and a novel bit of TT history. Very happy to have both the SL-10 and SL1200 mk2 in the listening room. Thanks, Ashley for this great resource!
Quick question — who is the authority on restorations for the SL-10? Thanks!
I’m not sure there is any professional authority on Technics repairs, which is why I advocate DIY. A lot of the information you see out there concerning Technics repair is wrong.
Good evening and thank you for your wonderful article. I also own a Technics sl 10 and would like you to help me with 2 issues if you can. 1. Since the MC 310 is pre-amplified by the same device, at which input of the amplifier will the RCAs be placed? Is it in the AUX position? 2. How do we find the grams of the arm since there are no numbers in the regulator, only lines? I am Christos from Greece and thank you very much for your time.
The preamplifier in the SL-10 is designed to add the extra stage of amplification needed for a moving coil cartridge to a moving magnet amplifier. So the turntable should be connected to the moving magnet or ‘phono’ input of your amplifier. As for the tracking force, these are very difficult to measure due to their design. The middle of the adjustment is 1.25 grams, the upper limit (a quarter turn clockwise) is 1.5 grams and a quarter turn anti-clockwise is 1.0 grams.
Good evening. Thank you for your time but let me not misunderstand. My amplifier DENON PMA 1560 has a phono input but on the front panel it has a mm or mc selector. The 310mc of the sl 10 is a mobile coil. So the option on the sl 10 button is mc. Connecting with Denon to phono the choice which should be mm or mc. Sorry to bother you but you saw one of the few who can give me this information. Thank you again.
This is a great article
I followed this and serviced my SL10 with new belts and lubricants. I’d stored this machine for 25 years on top of a book shelf, after an eBay find. Only recently did I find, that the tonearm would only travel two-thirds across before getting stuck. I found some replacement Technics bearing oil online (SFW0010 for an SP10 mk.2) and used general purpose silicone grease to lubricate some of the mechanism parts that clearly used ordinary grease before. Areas like the cable guide, plastic worm gear for the linear tracking mechanism, and the record clamp. For good measure I brushed out the optical sensors, which monitor the worm movement.
But even though I found many items I needed online, I don’t think I would have had the confidence to tackle it, without your article. The cartridge that it came with was a Shure, which I replaced with a moving magnet Audio Technica AT 300P, which sounds pretty good. A lovely surprise. Thanks for your guidance.
Excellent, thank you for your kind words on the article and I’m glad you were able to get your SL-10 going! I like Audio-Technica’s P Mount cartridges, there are some stylus upgrades available for them too which take the performance to a completely new level.
I have recently been using my SL10 I bought new in 1981. At some point I replaced the cartridge and the 310mc has been rattling around in a box for some time. Think the stylus is gone. Sounds like it would be worth it to get it refurbished if possible to have a back up. Who do you recommend to do that job? Thanks for the article. Will keep it in mind when/if I ever need to crack mine open. Sounds, though, like a daunting task for these older not so nimble fingers. Ha
Give Northwest Analogue a try. That 310 MC would doubtless hands down beat what ever you’re using now if it were re-tipped with a more advanced diamond. If you do have the cartridge rebuilt, servicing the SL-10 would be advised.
Thanks so much for the info. I checked last night and found that I had replaced the cartridge many years ago with a Shure Universal, not sure the model number as I just looked from the top of the turntable through the glass. I will contact Northwest Analogue.
I’ve no doubt that the Sure is a good cartridge, however if it was years ago it too is probably due a new stylus by now. With a fresh rebuild, the 310MC is one of if not the best cartridges ever manufactured for the P Mount system.
Depending on the Shure model, you might want to also look at the Jico Neo-SAS if they have one available for your model – I run both an EPC 310 mk2 and a particularly fine EPC p 202 with Jico SAS and would not be without either of them. My 310 is working very well, but when the time comes (and funds allow, which partly prompts this suggestion as retips are not cheap) I will be looking at someone like Northwest Analogue, or Expert Stylus.
Expert Stylus I think are also experts on the Shure … so if you find you have one of the top models that might be an option too.
Yes, I took off the Shure cartridge. The only markings on it are on the top,,,Shure Universal. I had a devil of a time getting that screw back in with my fat thumbs. Anyway, the cartridge seems to work okay. I didn’t even use the TT for 15 or 20 years. So, it is not like it is wore out. Thanks for all the suggestions though.
I am the happy owner of a SL-10 aswell. Using an Ortofon TMC-200 which I can only recommend!
I would like to hear if anyone have removed the muting relay successfully and maybe even considered to bypass the MM/MC switch and just hardwire fix it to MC (or MM)?
Today I have a vague balance problem when listening to MC, which I believe may be cause to the low impedance on MC making it extremely vulnarable to poor contact surfaces of both the relay and switch.
Any input/experience on this?
Haven’t attempted it, though the service manual should offer the necessary schematics and it’s a fairly simple circuit.
FWIW, on my SL-10, which I just had open to replace the tonearm drive belt and deoxit the MC/MM preamp switch, removing the 12 screws inside the top cover, and then just slightly sliding/nudging the cover’s record clamp housing/carrier toward the tonearm-at-rest direction, releases the cover from the central clamp. There is a screw attached washer that slots into a groove in the cover at the clamp housing. There was no need to remove the vision window. It _is_ necessary to be aware and mindful of the switch that slips through the upper cover at the hinge side, toward the base.
With regard to removing the inside, black cover of the base portion where the platter lives, First, the central ‘puck’ inside the 45rpm record adapter pop-up needs to be removed (it unscrews via the two holes in the puck – inserting a pointed tool in one of the holes and a few _gentle_ taps are all that is needed to get it moving, after which it and the 45rpm adapter along with a spring and a clear, plastic washer can be removed). Following that, the nut and wave washer securing the platter can be removed and then the platter itself. Finally, there are two, horseshoe shaped rubber plugs (toward the front by the switches and the top cover latch points) and two, round, rubber plugs at each side of the rear, toward the hinge points. Under each of these four plugs are screws which, along with those revealed by removal of the platter, must be removed to allow the black, base cover to be lifted. Once that is done, removing the metal shield over the right hand side of the circuit board provides access to the MC/MM switch for a squirt of deoxit, which cleared up the intermittent dead right channel sound problem for me. Hope this helps someone take care of their SL-10.
Thanks for this Rick, very useful advice.
I still have my SL-10 from the early 1980s. Last time I tried to use it, everything worked fine except the tone arm would randomly get stuck and stop moving along its track. Do you think it is possible that the track itself just needs lubrication? Can you suggest what to use? I realize this is probably answered in the guide, but since this is so specific I thought I’d ask. Thank you.
That is exactly what this maintenance guide will tackle. Over time the grease on the lubrication rails dries causing the arm to stick. Remove the rail, thoroughly clean both it and the inner bearing of the arm through which it slides and lubricate with a thin and even layer of white lithium grease. Oil the motor that dries the arm by dropping a few drops of synthetic oil beneath its pulley. Lubricating the main platter motor doesn’t hurt either, though that’s a significantly more involved process.
Hi Ashley
Very informative article… I am wondering if you can you advise on the “slow drop” arm mechanism on the SL10. Looking at the service manual it appears that bearing oil or similar needs to go somewhere near the base but I am not sure. I think these may be different to the slj300r tonearms you also wrote about.
Do you have experience of this? I have one SL10 whose tonearm drops smoothly and slowly onto the record, and I am hoping to improve another otherwise excellent model whose tonearm just drops onto the record. Wonderful decks!
Many thanks
The speed of the drop is governed by the tonearm dampening grease, which has a tendency to dry up. See Here on where it should go. As for obtaining new fluid, I believe SRM-Tech sell suitable grease. Hope this helps
Hi there! I read this with great interest since I have a SL10. I had a problem in that the tone arm did not move. After reading your posts I removed the cover and discovered the dial cord had come off. I put it back on using the diagram in the service manual, however I don’t believe it is positioned correctly. Do you have any suggestions?
What makes you think it is not positioned correctly? If you’ve followed the diagram you should be good to go. It’s been such a long time since I’ve seen the inside of an SL-10 that I’m struggling to remember exactly how the drive cord is installed. If the cord is tight, but the arm is still not moving, you may need to remove the tonearm rail, clean both it and the guide on the tonearm itself, and apply some fresh grease. You’ll also want to drop some oil into the motor that drives the tonearm, and check it is spinning freely.
Hope you are able to help please? This is the best turntable I have ever had but its giving me a problem at the moment. I have had it about 16 years after I found it still sealed in its original box on the tip I worked at! But (would you believe it) haven’t used it much as I got into computers! I last used it about 5 years ago to copy some LP’s onto my hard disc. Went to use it today and the arm sticks avter 2.20 minutes of playing! It seems to just pivot on its bar and then stops when it hits the arm ! Is this just a lubrication problem or something more sinister?? Your help would be appreciated.
That’s quite a find! Yes, sounds to me like it’s just a lubrication issue. Thoroughly clean and lubricate the arm guide rail and gears, and also remove the tonearm drive motor and drop a couple of drops of oil beneath the pulley to lubricate it too, turning it to ensure it spins freely. I have a post on here covering the Technics SL-J300R which offers pictures of a similar mechanism, but it’s pretty simple. One thing I will say is to remove the cartridge before you do anything, especially if yours is the original as finding one in the condition yours must be in is almost impossible. To do so, remove the screw located on the side of the cartridge near where it connects into the arm, and while also carefully supporting the arm gently wiggle it out of its slot.
Hi, I just purchased a SL -10 with an original cartrige. Sadly the deck does not work.
When I press ‘play’ the platter does not rotate nor does the arm move. If I open the lid and press the the button for record cleaning the platter does rotate, so the motor seems to be fine.
Any ideas anyone?
I would realy like to get this machine working.
Firstly, have you tried with a record on the platter? These Technics tables have a system in place to detect the record size, and to also prevent you dropping the stylus onto the mat with no record present. With a record on the platter, hold down the start button and see if the arm moves across the record. If not, perform the maintenance in this guide. Check while you’re inside that the tonearm motor turns freely.
Hi thanks for the reply.
Yes I tried it with an Lp on the platter but nothing happens when i press start. The platter does not turn and the arm does not move.
Regards, peter
I think it’s a stuck tonearm then. You’ll need to carry out the maintenance suggested in this guide. Be sure to check the tonearm motor turns freely.
Hi,
you think it is the tonarm? would that prevent the paltter turning as well then?
Peter
most of the Technics tables have a small microswitch at the end of the tonearm’s travel to tell the turntable that the arm is in the resting position. If the arm cannot move out, that switch isn’t released and the turntable won’t start up. Also check the small switch inside the turntable that senses whether the lid is closed. If you open the lid, you’ll see it protruding from the mechanism cover near the hinge on the opposite side to the arm. That switch is depressed when the lid of the turntable is closed, and without it the turntable will do nothing.
Hi Peter, were you able to fix your SL-10? Reading your fault description I suppose another cause than the tonearm-microswitch.
It could be a bad contact of the Cover-Switch (the one telling if the cover is closed, the one that is annoying when putting the top-cover back in place).
If this switch is not working properly, the main controller thinks the lid is still open, the only operation allowed in this mode is the simple rotation for cleaning.
Try to trigger the switch manually: open the lid, mask the 3 optical sensors with tape, push the white cover-switch (left behind the platter) with your finger and while keeping it fully pressed hit the start button. See if it turns and if the tonearm moves. Try to keep the start button pressed to move the tonearm manually. When you release the cover-switch, the platter will stop (eventually continue by inertia) and the tonearm return to its rest.
If that applies, you need to clean the contacts of your cover-switch. Since I have a SL-10 with similar problems (record playing is stopped at random position, as if the cover would be opened), I might be doing the same soon. Tell me if you need advice, I would write a post about it…
Hi Ashley
I purchased my SL-10 when it was new, probably in the late seventies?
Fired it back up again recently and there is a rumble, much like you would get when playing a warped record. Obviously this is more evident on a high volume setting but you can hear it with the volume set pretty low.
Just wondered if you had any idea what I could do to resolve this
Regards
Lou Jenkins
England
Sounds to me like it just needs a service. The rumble is probably caused by dry oil in the main bearing; and to fix, you’ll need to relubricate the bearing with some suitable bearing oil, such as the SRM-Tech black oil. Grab a copy of the service manual from Vinyl Engine, and disassemble the lower half of the turntable to remove the main spindle bearing. Clean it with isopropyl alcohol and lubricate well with the above oil. I’d also advise performing the tonearm service as above, as rumble can also be caused by the arm dragging on the main guide rail. It’ll take a bit of time if it’s the first time you’ve ever done it, but it sounds harder than it is. If you don’t want to strip it down yourself, there are still a few good Technics repair techs about who’ll do it for reasonable money. Either way it’s worth repairing as it’s an exceptional turntable.
Many thanks for your advice Ash – I’ll get it sorted
Regards
Lou
Hi Ashley, a friend of mine asked if I could get his SL10 working, alas, it does not have the original stylus but I found my Shure M95ED stylus fits although the housing is a bit wide.
Nevertheless when I tried playing a record I also found the tracking motor was not working.
After some fruitless browsing I came upon your excellent troubleshooting guide and I had no trouble removing the inside cover to expose the circuit board and drive motor which I lubricated with some Q20 and also lubricated the other gears and shafts. Right now I am happily listening to Winelight. Now all I need to do is find a suitable or original spec stylus.
I am in Cape Town on a very cold but sunny mid-winter day.
Thank you, Les
Thanks Les for your comment. I’m glad you found the guide helpful and were able to restore your friend’s SL-10 to working order. A bit of info for you re the stylus…
It sounds like the cartridge on your friends turntable has been replaced at some point. The original Technics cartridge, the 310MC, is a moving coil design and does not have a removable stylus, so your sure housing wouldn’t fit at all on that cartridge. I suspect that your particular turntable is fitted with a sure M92 or V15 (don’t quote me on those numbers, they’re just off the top of my head). Look at the side of the cartridge body (where the stylus fits) and see if you can spot the brand / model information of your particular cartridge.
Little tip; you probably know this already, but it’s possible to remove the cartridge by removing the small screw on the end of the tonearm, on the left-hand side as you view the open lid from the front. This will help you get a better view of the sides of the cartridge to find out exactly what you have.
Great article! I too had to do repair work on not one, but two of these little beasts last year. I found one in a junk shop for $30 with the original cartridge, albeit missing its cantilever, and a friend had one he got from a Goodwill thrift store for $25, with a worn but intact 310MC!. Both suffered from the same problem; the arm gear had stuck. A few turns and some fresh grease, and both were back to making music. Both tables had their label lights burned out, and one table had some microswitch issues for cueing the arm in fast mode, but beyond that, what great little tables! I was sad to see mine go, but I bought it expressly for a friend, not knowing its legendary status, and could not back down in good conscience. She uses it daily, and I couldn’t be happier.
Nice! Glad to hear of 2 more success stories. I didn’t keep mine, purely because it was in such good condition and was worth more to someone else than it was to me. But it was great fun while it lasted. 🙂