Technics SL-L20 Linear Tracking Turntable Service And Repair

This Technics SL-L20 recently came in for repair. The L20 remained, until now remained one of the the only two Technics models I have yet to see in person. I’ve owned, serviced and / or repaired at least one example of every Technics model sold in the UK, besides the SL-M3 linear tracker which was one of the later linear models and fetch mega bucks on the second-hand market. The SL-L20 is the complete opposite; a cheap and lightweight linear tracker with a mechanism that differs from that of most Technics linear turntables in that the arm and its mechanics are mounted to the turntable plinth and not a part of the lid. Cheap and pretty plasticky it may be, but it’s still capable of respectable performance with a bit of TLC.

SL-L20 Top View
SL-L20 Open Lid Platter View

I delved straight in to carry out the usual preventative maintenance necessary for all linear tracking turntables of this age. The SL-L20 is particularly easy to service as everything is accessed through the underside.

SL-L20 Overall Inside View

The linear tracking mechanism is inverted, allowing the arm to sit above the plinth and slide along a guide rail beneath. Otherwise it isn’t far removed from other Technics designs and as such suffers the usual problem of dried lubrication hindering movement. The grease was unusually difficult to remove, particularly from the bottom rail and drive cog. The little drive belt was in great condition and wasn’t replaced, though the mechanism did receive a thorough clean and the motor had a few drops of a light motor oil applied for good measure.

SL-L20 Arm Motor
SL-L20 Pulley System
SL-L20 Right Hand Arm Pulley Switch

This ‘table was reported to have issues with unsteady and incorrect speed. This issue is commonly caused by dirt and oxidisation affecting the speed control pots, marked VR101 and VR102 on the main circuit board. They were sprayed with a contact cleaner, and later adjusted through the two holes in the bass which allow them to be accessed with the deck assembled. The speed and size switches too were cleaned, necessitating removal of the board. I didn’t photograph the top of the board as to do so would have required desoldering the cables. Other Technics ‘tables use plug-in connectors which make the job easier, but cost-cutting didn’t allow for that here. Removing the board isn’t terribly difficult, though you must take care during reassembly to carefully align the switches as the switches themselves are fragile and very easily broken. Other electronic adjustments were spot on, and the arm tracked straight so I left them well alone.

SL-L20 Circuit Board

The next phase of service was the main bearing, which was the most unusual part of this design. The bearing plate is removed, including the ground and heat transfer plate which attaches to the main circuit board. The bearing and spindle are removed as one assembly, and the aforementioned bracket removed to allow the spindle to be lifted from the baring. I thoroughly cleaned both the spindle and shaft with alcohol before the bearing was reassembled with five drops of oil. The result is a smooth and silent bearing, and a noticeable drop in record surface noise during testing.

SL-L20 Bearing In Place
Sl-L20 Spindle Separated
SL-L20 Bearing Assembled

Final assembly involved a quick internal clean and a few drops of oil for the platter drive motor. This is a belt drive design with a small DC motor designed to be permanently lubricated, and thus difficult to disassemble for maintenance. Dropping a few drops of oil down the shaft was sufficient and reduced motor noise significantly. The motors are not completely silent, which will be particularly noticeable to anyone familiar with a Direct Drive technics which are inaudible. The motor sounds healthy and holds speed, and the drive belt looks to be a recent replacement. The platter and motor pulleys were cleaned for optimal performance.

SL-L20 Below Platter

Final cleanup complete, the original P30 cartridge was replaced with an Audio-Technica AT-311EP. Aftermarket styli for the P30 are readily available in .7 mil conical and .3 x .7 mil elliptical form, as well as some more exotic shapes, but the cartridge was sounding rather scratchy with a known good stylus and I have seen these cartridges fail in the past. It is important to note that some aftermarket styli for P Mount cartridges require that the tracking force be adjusted, which isn’t always easy particularly on these linear decks.

SL-L20 Arm Closeup

This deck isn’t laden with extravagant functions; a disc repeat function is about as advanced as it gets. Even speed and size are manual though there’s no provision for playing a 10” record automatically, and there is no mechanism to prevent you accidentally playing the mat and causing instantaneous stylus destruction if you forget to set the record size when playing a 7” disc. The deck will stop if there is no record on the platter by means of a lever beneath the platter which is attached to a momentary contact switch. A device on the platter is engaged when a record is present and when a record is in place will miss the lever beneath. When no record is in place, the platter will trigger the lever and stop the turntable before the arm has time to move into position. It’s a primitive if not clever system but requires that the original mat be used and correctly aligned such that the lever can protrude through a small slit in its surface.

SL-L20 Switch

Cuing is electronic, though the arm drop speed is sharper than I’d ordinarily like. The arm lift damper was serviced, but it has limited travel which doesn’t allow for a slow descent. The arm is largely plastic with an effective length of 105 mm and fixed vertical tracking force of 1.25 grams, assuming a 6 gram cartridge is used. It takes a T4P plug-in P Mount cartridge, with a P30CS installed as standard and the stock EPS-P30CS 0.7 mil conical stylus.

This deck wasn’t Technics’ finest hour. It’s their lowest end drive mechanism coupled to their cheapest linear arm. If you want a true taste of what a Technics can do, you’re better off finding one of their many direct drive models. But if you dig the conveniences and just want to spin a few records, the L20 sounds quite respectable and is very simple in its design, with little to go wrong given a bit of preventative maintenance. I’ve yet to come across a Technics that didn’t at least sound good, and I had great fun spinning 7” singles on the L20 before returning it to its rightful owner ready to deliver another few decades of faithful service.

By Ashley

I founded Audio Appraisal a few years ago and continue to regularly update it with fresh content. An avid vinyl collector and coffee addict, I can often be found at a workbench tinkering with a faulty electronic device, tweaking a turntable to extract the last bit of detail from those tiny grooves in the plastic stuff, or relaxing in front of the hi-fi with a good album. A musician, occasional producer and sound engineer, other hobbies include software programming, web development, long walks and occasional DIY. Follow @ashleycox2


  1. Trying to decide – repair or toss? Must have been 20 years since last using this Technics SL-L25. My wife’s Dad gave it to her as a gift when she was a teenager, now suddenly our teenage daughter wants to play vinyl records. The turntable wouldn’t spin. Took off the platter and saw the belt had completely disintegrated. Ordered a new one, put it on, now the platter would spin but the speeds were variable and way off. This article was supremely helpful in determining what the issue was. Alas the time and effort required to restore this particular turntable has me leaning towards just leaving it into the electronics recycling area. A bit of a shame because the lid and the feet are all pristine, and I’m seeing a lot of folks without that. Thanks for the concise info!

    1. absolutely worth fixing. Anything vintage you buy will need a service regardless of whether it is claimed to work, and you won’t get anything new that performs as well as that Technics for under £200GBP or $300USD, if not more. It’s really not that much effort to fix. Even the cheapest Technics linear trackers had parts in common with their most expensive models, so they perform very well when they’re rebuilt. Incidentally your SL-L25 is a better turntable than the SL-L20 in this article, even though they are cosmetically similar. My advice would be to fix it, or if you don’t want to fix it at least sell it or give it away to someone who will. I bet half an hour of work would have that thing working like new.

  2. Ashleym
    just found your site. I have an SL L20 about 35 years old, not used for at least 10 years, just started recording my LPs down to the computer. The bar under the platen appears to have silicon grease on it. A couple of questions: First, the arm will stop randomly usually within the first 3-4 minutes of playing and just repeat, it is not the LP as different LPs give the same result. Second question, if disassembly is required what does it take? Third question, is it possible to get replacement isolation feet and springs and a new 45rpm center “slug” for the platen? Thanks in advance, Arthur

    1. Yes, that issue is likely caused by dry grease. disassembly and reAssembly is not difficult, just take your time and take pictures as you go. As for obtaining new feet and a platter centre, most technics linear turntables used the same parts. My best suggestion would be to find a broken one with the parts you need. There are usually a few with cracked lids or damaged arms about that make good parts units.

      1. Ashley,
        I cleaned the silicone off and put new, lighter grease on the bar and on the plate behind the carriage which then moved easier. The tone arm drive belt looked and felt very loose so that and the turntable belt ($18 total) were replaced and now the arm will cue up and play thru. Thanks for running this site your instructions and photos gave me the nerve to try it. Still looking for the isolation feet but the turntable works.

  3. Thank you Ashley for this excellent write up! I have a SL-L20 that served me well since I first purchased it many years ago in a store. However, last year I started to have some issues.

    First the platter spins fast at 33. You mention POTS VR101 and VR102 in the circuit board in the photo above. I see two small access holes located behind the front right foot. Are those it? What adjustment exactly are needed? Do I need a special tool?

    Second, I get a strange loud clicking noise that I believe to be associated with the tonearm movement. It clicks when the tonearm moves from its rest position to the records edge. The clicking stops when the tone arm descends, but picks up again after a minute of playing. Its a series of clicks, which stops and picks up again. The interval between each clicking series gets shorter until it clicks constantly. Are you familiar with this sound and its possible source?

    Is there any special grease and lubricants that you use to service?

    The SL-L20 was my first turntable purchase, so I like to resurrect it if possible. Thank you very much.

    1. Those are indeed the correct pots, those access holes are to enable adjustment without removing the base. They are adjusted with a small flat-blade screwdriver, though ideally you’d use a ceramic adjustment screwdriver. You can buy sets of them on eBay / amazon for very little. I’d probably spray some switch cleaner (deoxit or servisol super 10) on those pots before you adjust them.

      In terms of the clicking noise, it could be a number of things. It could be the mechanism just getting stuck, which is most likely. There could be a dirty switch contact somewhere. The main drive gear could be damaged, but I’ve not seen that happen. It’s been a while since I had an L20 apart but from memory there aren’t many parts that can click if they go wrong. Start by cleaning the mechanism thoroughly and run it dry briefly to see if the noise persists.

      As for grease. A light synthetic motor / gearbox oil (not engine oil) or general-purpose 3 in one motor oil in the drive motor and the arm drive motor, drop it beneath the pulley and let it find its way down the shaft into the bearing. A synthetic oil should also be used to lubricate the main spindle bearing, and it should spin silently. White lithium grease or PTFE grease is good for the tonearm drive gears and support rails, but ensure the rubber tonearm drive belt stays clean.

      1. Thank you Ashley for your valuable time and insights. Regarding the pots adjustments, do you know why there are two? Is one pot specific to 33 and the other to 45? Thank you again.

        1. One is indeed for 33 and the other for 45. Without re-downloading the service manual I can’t remember which but as both will probably need adjustment you can easily find out via trial and error. Other pots on the board relate to the linear tracking mechanism and should not be adjusted unless it still doesn’t work after a mechanical restoration.

          1. I know this update is looong overdue, but wanted to share the turntable is up and running again! Turns out…

            1) I needed a new tonearm o-ring belt (root cause for causing the clicking sound downstream in the tonearm mechanism).

            2) I realized I purchased the wrong platter belt at the time. Correct belt fixed the speed issue I was experiencing.

            Glad I was able to save it from the trash bin. I always liked the low-profile look of this table.

  4. Hello, thanks for all the information.
    My SL-L20 is descending the arm too fast, causing a loud bump noise on the record and even a little jump of the needle. Does it have some kind of fine tuning to soften the fall? I know you said the arm is not slow, but mine is like a free fall.
    Also the arm is not starting precisely at the beggining of the record. Appreciate you help.

    1. The speed of the arm drop is controlled by a low viscosity damping grease in the lifter mechanism. To restore a slow drop, that part of the arm must be disassembled and fresh grease applied. It’s been a while since I worked on an L20 so I can’t tell you exactly where the part is, but it shouldn’t be difficult to spot as it is linked to the platform on which the arm sits when it is in its raised position, near the arm’s pivot point.

      The position that the arm drops is a simple adjustment, I believe hidden under a screw cap near the base of the arm. Note though that if the arm drops to quickly the stylus will likely jump and thus the arm will miss the intended start point.

  5. We inherited a Technics SL-125 from my sister-in-law. It turns on and arm goes to play but it doesn’t spin at all. Does this sound lime it needs a new belt? It makes a whirring noise as if it wants to play.

    1. Sounds like it just needs a new belt, maybe some fresh oil etc if it’s been sitting for a while. Shouldn’t take much to get it going.

  6. Replaced my cartridge on my SL-L20 and not getting any sound from turntable. All other components work and produce sound. Everything is lugged into correct location. Is there anything internal that would prevent sound?

    1. No, there isn’t. What cartridge did you use, I presume it is firmly seated in the socket with the retaining screw in place? Which cartridge did you install?

      1. I replaced it with a audio Technica AT85EP for the P mount turntables. Went firmly in place and the screw was inserted back in.

        1. Very strange issue. Did the turntable work before and does it work if you reinstall the original cartridge? You either have a defective cartridge or something wrong with the turntable, though I can’t think what would cause that besides perhaps faulty wiring. As far as I recall the L20 doesn’t have a muting circuit. I presume you have the turntable wired into a moving magnet phono input on the amp or an external phono stage.

          1. Everything worked fine the stylus needed to be replaced point was worn. However it worked last time it was used a few years ago. Just started getting back into vinyl again. Old stylus would do the same thing as new. I be just replaced with new input wiring. Last thing. everything is where it belongs on Sansui G9000 reviever

  7. Ashley

    Thanks for the excellent write up on the L-20.

    I purchased one of these some 20 years ago and it did perform well. However it has since been replaced by an SL-QL1 and DL1 which without question perform at a much different level!

    I have not used the L-20 in years, but given your detailed notes on the necessary maintenance I think I may pull it out of storage and could put it into service to test newly purchased used LPs – saving wear and tear on the better stylus on the QL1 and DL1

    1. Definitely worth resurrecting and a great idea for usage. The QL-1 in particular is one of the best linear decks Technics made, I personally prefer them to the SL-7 / SL-10 / SL-15 which are generally considered the best of their range. If yours has a good cartridge body the P30ES / P33ES is the correct elliptical stylus replacement and will get the best from the deck for very little money. You can find the full service manual Here which details the disassembly and adjustment procedures, for which you will need a DC voltmeter.

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