Wednesday, May 18, 2011

Fixing Unstable Turntable Speed

Technics SL-1300 direct-drive automatic turntable
Am I the only one who finds it odd that in 35 years,
no one ever removed that giant vinyl decal?
The thrift store can be a good place to buy turntables as well as records. You might have to be patient and keep checking, but it's not unusual to find a nice, vintage workhorse capable of outperforming many of the new turntables available today, and for a fraction of the cost.

I once found a beautifully kept Technics SL-D2 that barely needed so much as a light dusting. But most of the time there has been at least one or two things wrong with the thrift store turntables I have encountered. This Technics SL-1300, which I recently picked up, was missing the headshell/cartridge/stylus assembly, and while the sticker on the dust cover states that it has been tested and the "turntable spins," I could see by the wildly fluctuating strobe pattern, when I tried it out in the store, that the sound was going to be wobbly, to say the least. But for the low, low price of only $3.00, it didn't take long for me to decide to grab it. I reasoned that if it couldn't easily be fixed, it was still well worth buying just for the platter mat alone.

Symptoms

The video at right demonstrates the erratic strobe pattern and sound. The speed adjustment controls were extremely touchy. I only had to lightly tap them to make the platter spazz out even worse. There was no way you could stabilize the speed, and the turntable was unusable in this condition—unless you wanted to play background music in a funhouse. Watch the bottom row of dots. Those are the ones that should be appearing stationary.






Diagnosis
What can happen is, the components that allow you to control the speed get dust and crud gunking up their internal contacts, causing them to work erratically. It's the same thing that causes crackly, touchy, volume controls. Eventually, the potentiometers ("pots") and switches need to be cleaned with a good electronic parts cleaning fluid. Often, this is all that is necessary to get things working properly again. I was able to fix this problem without buying or installing anything. The only tools needed were basic Phillips-head and flat-head screwdrivers.

Solution
CRC QD Electronic Cleaner
There are several brands of cleaning fluids available that should do the trick. DeoxIT® by Caig Laboratories has a very good reputation, and is pretty much universally endorsed. I already had this can of CRC QD Electronic Cleaner hanging around, so that is what I used. Make sure whatever you use, that the label states it is safe on plastics. I should mention that a lubricant is recommended (if not essential) when/after cleaning potentiometers to keep them operating smoothly and to protect against premature wear. DeoxIT® already has a lubricant mixed with the cleaner. The CRC is a very effective cleaner, but contains no lubricant. Now that this turntable is spinning properly again, I plan to replace its audio cables. At that time, I'll probably go ahead and lubricate the pots I just cleaned.


CAUTION: Always be sure the power plug of any electrical device is disconnected from power source before working inside device. Always follow standard safety guidelines for working with electrical devices. We at Thrift Store Record Report are not responsible for any damage to persons or property that may arise as a result of unqualified service personnel attempting turntable repairs after viewing the materials posted to this site.

Disassembly

Tonearm locked and platter removed
Before turning the unit over, lock down the tonearm, remove the mat, and carefully remove the platter. Some turntables may have screws on the platter, or a retaining ring or clip of some sort around the spindle that will need to be removed first. With this Technics, and many of the other turntables I have encountered, you only need to lift the platter. It might be a little stuck at first. You can lock your thumbs in the holes and push downward with your fingers on the base if you need a little extra leverage. Try to pull up with equal pressure on each side. You have to be especially careful not to damage the magnet assembly attached to the underside of the platter on these direct-drive turntables.

Inside view of Technics SL-1300 turntable
The main speed pots and speed selector switch
are in the upper-left corner
I left the dust cover on and flipped the unit upside down on a large, folded bath towel. I know this leaves a chance of cracking the dust cover, but I've not broken one yet, and it is easier for me this way, so I continue to take my chances. If you rig something up to support it without the dustcover, just make sure it is stable enough and that nothing can touch the tonearm assembly. Next, I removed the screws from the base. The feet did not need to come off, as on some turntables. There were two screw lengths. The shorter ones went around the perimeter; the longer ones closer to the middle. I pulled all the screws out (a magnetic tip screwdriver comes in handy here) and put them aside where they wouldn't get lost. Some people like to only loosen them, so they lift out with the base, still sitting in their respective holes.

Getting Down to Business

The primary targets are the main speed/pitch adjustment pots. I cleaned only those at first, then did a quick test, and found that the speed looked greatly stabilized just from those parts getting cleaned. However, to be thorough, I went ahead and cleaned the speed selector switch and the more hidden set of speed control trimpots. I also oiled the motor shaft while I was at it.






The video above illustrates, step-by-step, all of the work that was done, and is a live-motion companion to this written article. It even has a pretty snappy soundtrack—so check it out!


The main speed control potentiometers
Spray the cleaner in any openings you find in the components. The pots should have sizable openings where the three connection tabs are attached, as well as another small one around the outside of the case. After spraying fluid inside the housing, the pot shafts need to be fully rotated back and forth many times, then repeat the spray/rotation procedure at least once or twice more.




Spraying speed selector switch
Next, I cleaned the speed selector switch by spraying into the cracks where the plastic plunger piece comes out of the housing, and in some adjacent slots, as well. The switch should then also be worked back and forth several times and sprayed again. This fluid dries very quickly and doesn't seem to harm anything it gets on, so I don't usually worry too much about over-spray, but you can always surround the parts you're spraying with a rag or paper towel to catch the excess.




To get at the second, less accessible set of speed controls, the circuit board located next to the main speed pots must be removed. It was only a matter of taking out three Phillips-head screws and then lifting the board straight up while wiggling it a little bit to free its connecting pins from the holes they mate with on the motor board.

Variable resistors 1 & 2
aka VR1 & VR2
Once the circuit board is unscrewed and flipped over, it's an easy job cleaning these parts, as they are not sealed in housings and their track and wiper contacts are more exposed. Spray, fully rotate shaft back and forth, and repeat the cycle, just like with the first pots. After everything is reassembled, these trimpots will need to be adjusted first, to give the topside speed controls the range necessary to get the platter rotating at the right speed.



Oiling motor shaft on Technics SL-1300
As long as the platter was off, I figured it was a good idea to also oil the motor shaft—especially since this is something else that can affect the speed. Technics recommends doing this after every 2,000 hours of service. Since I bought this turntable used, several decades after it was made (and while it's in pretty good shape, it doesn't exactly look like it's been babied), I think it is probably overdue by now. The owner's manual and the sticker on the platter insist you use only the specially formulated Technics oil, but I doubt it is necessary. I would certainly use it if I had some, but since I don't, I'm inclined to just make-do with an acceptable substitute when working on a broken-down, three dollar turntable. I think a good light oil, such as sewing machine oil is fine for this task. If you would like to get the official Technics oil, you can find some available for purchase at the Kab Electro Acoustics website. I used something called Lubit-8. I like the precision needlepoint applicator and the fact that it is supposed to be compatible with all oils and greases, so it should mix well with any other oil that has been applied in the past. No matter what kind you use, you are only supposed to apply two to three drops.

These are basically "set and forget" trimpots
I didn't note the positions of VR1 & 2 before commencing to vigorously rotate them, so I reset them to the midway/twelve o'clock position. After trying out the turntable, I found they needed to be moved to the one o'clock position. VR1 and VR2 must be set correctly before the topside controls will have the range needed to get the platter spinning at the right speed.






Results
The video below shows how the turntable is running very smoothly now.



A nice Technics turntable database can be found at Vintage Technics 
 

A great library of free turntable user manuals, service manuals, schematics, brochures, and technical documents is located at Vinylengine

54 comments:

Tom said...

Interesting post, thanks. I have a similar-ish problem with a Technics 1210 mk2 except once turned on the platter spins out of control, thought it could be a blown fuse as it worked perfectly up until now. May give it a squirt of cleaning fluid when I get a chance to buy some.

Tom

Guru Chaks said...

Thanks for your really helpful tips. I too have the same problem and my technical friend agrees with you. So I will do the needful as per your suggestion - CLay

Directdriver said...

Hey! I have an SL D2 I'm experience speed problems with, do you think I could follow this procedure in order to fix it? Is the design very different from the 1300?

Record Reporter said...

Hi Directdriver,
Yes, any turntable with speed control pots and/or switches can benefit from this procedure.
Cleaning these parts is usually the best and easiest first thing to try when your turntable won't hold a steady speed, especially if it's a direct-drive like your SL-D2.
I haven't disassembled my own SL-D2, but I think if you unscrew and remove the base, it shouldn't be too hard to locate and access the pitch/speed control pot and switch. The pot case should look about the same as the one shown here for the 1300.

Paul said...

Thank you very much for this information. I have a Technics SL-B200 turntable that I haven't used for years due to the variable speed problem. I removed the bottom and sprayed the speed control pot per your instructions, while moving the knob back and forth. It fixed the problem perfectly.

Record Reporter said...

You're welcome Paul. Glad to hear it worked out for you. Thanks for the comment!

SCHROEDER said...

Thanks a 1,000,000 for the finely detailed videos, directions and pictures on this procedure. I was ready to hunt down another turntables because of the fluctuating speed problem that made listening to my vinyl impossible to enjoy. I figured I punch in my problem on Google to see if there was cheaper solution than buying a new turntable and came across your youtube videos and site. I just finished following your directions on my Technics SL-1300 and I am now enjoying the first non fluttering spin of TOMAHAWK - Anonymous and my ears are smiling!!!

Record Reporter said...

Yes! Another turntable is back in action! Glad to hear this worked on your SL-1300 Schroeder.

Unknown said...

Hi and Happy New Year!
At least it is for me now that I found your exceptional step by step. I too am the proud owner of a found SL-1300, left behind in an empty apartment but missing the ground wire and head shell. Replaced those items, then whenever I tried to play a record, speed was all over the place. I was just about to post it on Craigslist as a fixer but for a $3 investment in some CRC 2-26 cleaner/lube and 15 minutes, I now have a functional turntable. Now I can listen to the Christmas songs I didn't hear before I have to wait another year. Thanks again.

Record Reporter said...

Thanks for the comment, James. Glad to hear you were able to hang onto your turntable and will be spinning records on it into the new year now!

Unknown said...

I just did this on my SL-D2. There aren't the adjustment screws under the slip mat. Also, removing the entire circuit board would be an ordeal. Luckily on the SL-D2, the switch and the pitch potentiometer are at the very front(edge) of the board. So I just sprayed home computer cleaner compressed air at them, then some sensor cleaner. Works awesome now! Thank you so much for this very instructive post.

Record Reporter said...

You're very welcome, Tristan. Good to hear you found a way to make this work for you. Thanks for the comment!

SURVEY SURVEY SURVEY said...

I want to sale mine...How mush can I sale it?

Thanks.

(got 2)

Record Reporter said...

Check the completed auctions at eBay to get an idea of how much they are selling for. I'd guess you can probably get somewhere between 100 - 200 USD on average, depending on condition. It might be easier to sell locally so you don't have to pack it up. If you do ship it, just make sure you pack it properly so it doesn't get damaged.

Unknown said...

You Sir or Madam, are performing a public service. Keep up the good work.

I almost marked my old JVC L-A31's for the recycling bin, but then decided to look up whether the problem could be solved. It can, and thanks to your simple and pleasant tutorial, I did.

I have been using these turntables to practice mixing house music. They are serving me very well, and until I can afford and justify a pair of Technics 1200s, I hope to put them to use for as long as possible.

Thanks again!

Record Reporter said...

Thanks for the positive comments, Greg and Todd! Glad the tutorial helped you both out!

Unknown said...

I just followed through with your instructions and unfortunately in my case it is not solving the issue. I have also noticed a bit of a ticking noise too. What might it be? Is the motor possibly at fault? If so where do I get one (I'm in Australia). Thanks again!

Unknown said...

Hi,
I have a technics SL-1350, it looks pretty similar to the 1300 did you ever change the pilot lamp on these models? I find it very hard to find the part numbers of the lamp .. Thanks for this awesome blog!!!
Julie

Record Reporter said...

Julie, I never had to replace the lamp, but it looks like that part number is SFDN130-01A. That is the part listed in the SL1300 service manual and it appears to be the same part used in the SL1350. For informational purposes, here are a couple links to places that used to stock the part. You might still find one for sale on eBay. Good luck!
http://www.encompassparts.com/item/432566/Panasonic/SFDN130-01A/Replacement_Lamp
https://www.partstore.com/CompatibleModels/Matsushita/Panasonic/SFDN13001A/New.aspx

Marc, maybe the ticking noise is something to do with the main bearing or possibly that the platter is not seated well? If you haven't done so already, try a few drops of oil down around the spindle and make sure the platter is well seated and not rubbing on anything. If the noise only occurs when the motor is running and not when you spin the platter by hand, then I guess the motor could be at fault. Not sure where you could get a new one. eBay might be the best bet for that too. It's probably not a cheap part though, so try to make sure that's really the problem before you go for a replacement.

Unknown said...

Thanks so much for the fast answer!! SFDN130-01A, does anyone know the power con, amp, or any still existing replacement part number that I could use? They do not show the spec on the sites. I have a strobe light mounted with a resistor that i had receive for my Bose 901 equalizer. was wondering if I can use this on my 1350 tt.. Don't wanna blow anything up :D

Unknown said...

I have a similar problem - the speed is very unstable. I have a Technics SL-Q300 and have taken it apart but it looks very different than your model. Where can I find the speed controls, etc. Thanks...

Record Reporter said...

Hi Tim, It looks like that model may not have any speed adjustment controls/trimpots at all (see this Vinyl Engine forum thread: http://www.vinylengine.com/turntable_forum/viewtopic.php?t=18660 ). At the very least, you can clean the speed selector switch if you haven't already done so. Sometimes that alone will fix the problem. Just make sure to spray inside of the switch housing from underneath and slide the switch back and forth a bunch of times.

Unknown said...

Great text and video!! I'll do this to my SL-1300. Do you have anything to say about arm's autostarting fixing?

Unknown said...

Hello! I have an SL-1400 that, over time, started experiencing this exact issue. Unfortunately, once I finished meticulously cleaning the pots, I go to turn it on: the light turns on for half a second, then becomes unresponsive. It appears that it won't turn on now. Before taking it to a pro, I was hoping you may have some light to shed. [A bit about my situation: I'm an experienced bicycle mechanic (good with following directions) and like you, bought my record player for cheap ($75) and am not scared to trial/error].

Record Reporter said...

Hi Jordan,
Sounds like you might just have a blown fuse. If you haven't done so already, look at the fuse(s) that should be attached to the circuit board and see if the filament inside is broken or if the glass looks blackened (or check with a continuity tester). There should be at least one and maybe two fuses. That's about the only thing I can think of to tell you...

eko cahyono said...

hi i have a problem on turntables mitsubishi dp-300 on speed, once sy spray with cleaner and play with good result. but the problem that now arises again and again I give cleaner results are still problematic ... if there is a solution of your gratitude. echo

Record Reporter said...

Hi Eko,
Sounds like maybe the whole speed control pot (potentiometer) finally needs to be replaced with a new one.

eko cahyono said...

yes maybe you're right ... I am looking for a pretty hard most 2k pot 1k or 5k. thank you

VladDrakul said...

For the ones who have a sl-d2 and are reading this, I need to say that the pots aren't acessable just by removing the bottom cover (sadly).
You will need to unscrew circuit boards (something I haven't made).

Unknown said...

tried this on an old jvc and it worked like a charm thanks. even though this was a secondary turntable for me this info was very helpful thanks.

Record Reporter said...

Great, glad this helped! Thanks for the comment.

Unknown said...

My Sanyo TP1012 turntable had the speed issue. I tried your procedure to clean the pots and switches using CRC 2-26 (contact cleaner/lube - $2.98 at Home Depot) tonight and I am happy to report it now works perfectly! Thank you for sharing your expertise. I have already paid it forward!!!

Record Reporter said...

Jeffery, thanks for the comment and details about the CRC cleaner/lube you used. Happy to know this article helped you get your turntable back in action!

Reed Fleming said...

I need to try this but wondering if the "Electronics Cleaner" is not much more than a mixture of isopropyl alcohol and distilled water.

Goatee said...

hello, i have the same unstable speed problem with my SL1200MK2 turntables. If i turn on the turntables for the first time, it will still act normally but after a while maybe about 3-5 minutes, the speed is getting very unstable just like at your video. And also if i press the start-stop button, it stops for 2-3 secs but after that it spins again. I'm very confused here. Could you post a video how to fix this problem please?

Reed Fleming said...

Ok, I tried this on my SLD2 and in the end it worked but as noted above, the SLD2 is configured differently than in this video. In order to get under the circuit board I had to dismantle quite a bit. Once I flipped the circuit board over, there were no adjuster pots as in this video. So the only place to spray the electronics cleaner I could have done without removing a single thing.

Fortunately I managed to get things all back together and everything works, most importantly the speed control! So nice to see the strobe light nice and stable.

Unknown said...

Hi there, I recently picked up a 1300 model and gave all your instructions a try. Thankfully it worked! I did notice, though, that my VR1 trimpot is a bit damaged. Do you happen to know where I might be able to purchase a replacement VR1? I've been looking online and have been coming up empty. I did notice that after a couple plays, I have to adjust the pitch to find the sweet spot. Wondering if that damaged VR1 is the culprit for this issue. Either way, I really appreciate your taking the time to post this. Thank you!

Unknown said...

Great tutorial! I just fixed both of my turntables following your instructions. My Kenwood KD 3100 had not been keeping a steady strobe for a few years so I picked up a Pioneer 510A to replace it which eventually ended up with the same speed adjustment issue.
They are both working great now and I am rich in working turntables! Even my dad commented: "Wow, two record players!"
Thank you!

Paul V said...

Pleased to say that squirting cleaner into the speed adjust knob on the front of a wonky SL D2 toatally did the trick... Thanks

Unknown said...

Hello! I've just bought a Sony PS Q3 turntable and it has a very slight speed unstability. Underneath there is the 33 and 45 adjustment pots, I've changed the belts but it is still noticeable, specially with 7" records. Do you think I should try this same procedure? Thank you!

Record Reporter said...

Gonzalo, yes, I would give it a try. There is a good chance it will help your turntable and it is not too difficult to do. Good luck!

Antony said...

I just followed this for my SL-1700 .... the base doesn't come off the same way when turned over - the direct drive wires are still connected ... BUT there is enough room to spray the pots and the two spindles ...

The Technics oil was a great buy ...

All put together and bingo works like new ... I have had this turntable since early 1977!!!!!

Listened to a bunch of vinyl last night!!!!!
Thank you.

Tom said...

Hello, I have some wd-40 electrical contact spray that I play to use for this, however I don't think it contains lubricant. What kind of lube would you recommend?

Tom said...

Nm. It looks like fader lube is what I need.

Record Reporter said...

Hi Tom, I meant to reply sooner but kept forgetting. The Caig fader lube looks good. Looks like it both cleans and lubricates. Might get some of that myself once I run out of the stuff I've been using. Good luck!

Unknown said...

My Technics SL-B2 has this exact same problem. However, I can not locate the potentiometer. Where do I apply the spray? I hope you can help. Thanks

Reed Fleming said...

Unknown, I would start with spraying right at the pitch control dial without removing anything first. Try to shoot the spray through the gaps to get behind the wheel.But don't overdo it. Just a few shots, let it air dry and then if that doesn't work. Watch the video to remove cover and get to the two potentiometers. They are metallic cylinders. See the photo.

SocketCreep said...

I have a Techniques SL-BD22 which has not been used for quite some time. I replaced the original (red) belt which had disintegrated and put on a new cartridge, only to find the erratic speed problem. I'll try the method you described as I'm sure it will be similarly implemented. I don't have the contact cleaner yet, so I have to find some somewhere. I need some anyway for the Pioneer SX-450 ($25) that I found in a thrift store which works perfectly other than the scratchy controls. BTW, this was the model stereo I owned when in college in the late 70's. It was truly a blessing to find another one. It's a good thing I did, since a lot of the newer receivers do not have the phono inputs.

Unknown said...

Super description and video! Everything went smoothly, but most importantly it worked! I can't believe I waited this long to correct my unstable speed. Thanks so much for putting this together, as it looks like it was a lot of work.

Unknown said...

October 2020 still worked fine on a Sl 1500. I love this stuff buddy, keep up!

Ben Mendes said...

Did the same on my sl-1410 , but still the speed kind of rythmically moves up and down a bit. On 33 and 45 same issue. It is stable in a way but fluctuates a bit . Any suggestions??

Hobbyman said...

Thanks for a clear and informative post. Does this procedure also work on a belt drive TT? I have both a Thorens 125 and a Mitsubishi DP 15, both of which have unstable speeds.

Record Reporter said...

Hobbyman, yes, you can use an electronics cleaning spray to clean the pots and switches on most any device that utilizes such parts. Try it on crackly volume controls on your receiver/radio as well as the speed controls on your turntable.

Gary said...

My turntable turns the correct speed but the LED speed light indicator on my SL-1310MK2 is not totally lighting up, a small portion in the middle of the 3 is missing of 33 and a small part of the 4 in 45. I saw a u-tube video of someone taking a similar turntable apart (SL-1210MK2) and saw that the part number under the speed window was "GL 7R204" but I cannot find that part anywhere on the internet. I do however see on the internet a part number SVD GL 7R204 but there's no picture of it so I don't know if that is the part I need or not, could that SVDGL 7R204 be the correct number?