Ahh, you have one of THOSE capstan setups, aye? I've heard horror stories about these, but my SXs' were never 'fortunate' enough to have this. This was included in 'higher end' models to improved the gripiness between the pinch roller and the capstan, since those pitiful excuses for rollers cannot do their job on their own when paired with that mechanism. This would ultimately improve the wow/flutter for the length of the rubber's usefulness. The problem with this is there is no way to find a replacement, unless you somehow make one, and you'd have to be pretty crafty (pun intended) to do this. You could get a lower end SX without the rubber and simply swap the capstans. The lower end units have a sanded metal band on the middle of the capstans. Your pinch rollers are surprisingly fresh looking BTW.
As far as I can tell, it has been used very little; a gift from a business trip in Japan. The exterior is also basically mint. Anyway the reverse capstan bands just disintegrated with a minimal friction using a cotton swab soaked in alcohol; as did the original belts, and the clutch ring, and maybe the gear under the main flywheel ... definitely a reliable transport ! Without the bands it plays the same way - not good. I'm done with the RQ-SX serie, if I want a Panasonic I will look for a "lesser" RQ-S or RQ-X. There is no point in trying to fix the unfixable, I'm quite sure that even with different flywheels it would sound the same, there is something wrong with this unit.
Hello, Since this thread still comes up high in search results, I'm signing up and reviving it to share my experience, which I hope will serve people trying to fix these devices. So I've got two RQ-SX32's, one with the small rubber bands on the capstans, and one with the sanded capstans. I've bought new belts and clutch retaining discs from Marian at fixyouraudio.com for both units, naively trusting they will just work. Just like with everyone here, both units had horrible flutter making them completely unusable. Additionally, there was a nasty ticking in both units during playback. So here's what I did, along with some comments: First, heads up. This is not easy. You will immediately distroy your unit if you're not VERY SKILLED. Secondly, tools and materials: - Usual stuff like screwdrivers, tweezers, cotton swabs etc. - Solder station, wick tape. - Air duster with a narrow tip. - Enough pure IPA. - Soft brush. - Oil (Isoflex PDP 65 oil from fixyouraudio.com will do). DISSASEMBLY Remove battery door cover, front cover - 6 screws, door - 4 screws, frame. Remove mainboard: - 5 screws. - Desolder: motor - 4 points, selenoid - 2 points, negative battery contact spring - 1 point. - Detach head cable ribbon - just pull. Remove head and pinch roller assembly - 2 screws. Remove motor: - Remove the split washer. - Pull strongly the upper part of the rotor - carefull, your're putting pressure on the stator. - Remove the stator - 3 screws. - Lift the lower part of the rotor. Remove selenoid - 1 screw. I suggest removing the original plastic clutch retaining disc (it was cracked on both my units) by removing the split washer. Order a brass one from fixyouraudio.com. CLEANING Prepare a flat bowl with about 1cm of IPA. Completely immerse the tape transport in IPA. Use the brush to clean everything, but be carefull with the rubber ring on the capstans (if existing). Move the gears and all moving parts as much as possible. Then blow it dry with cold air. Do the same with the mainboard. Brush clean any residue. Don't worry, it won't melt, but don't keep it in IPA too much or the flexible button covers may come off. Then blow it dry. Submerse the head and pinch roller assembly and brush it clean. Aditionally, use cotton swabs on the pinch rollers until no more residue is picked up. Blow it dry and wipe the head with a clean dry cotton swab. Use the same method to clean the motor and selenoid. GREASING Don't drown everything in oil. It will add surface tension and cause dirt buildup. There are just two points on the tape transport that I personally consider that should be oiled: - Motor shaft. - Selenoid plunger - if plunger travel is incomplete, the gear controlling tape direction will not lock completely and will cause the ticking sound during playback. If the switches on the mainboard feel a bit stuck, you can use a fine drop of oil to ease them, and then clean carefully the area with a cotton swab. ASSEMBLY Reverse the steps used for dissasemblying the head, motor, selenoid. Head ribbon cable is easier to insert before installing the mainboard. All threads for the mainboard screws are plastic. Dont overtighten - I have cracked threads on both units. Checklist before soldering the mainboard (I had to desolder several times for forgetting some): - Motor screwed in place, split washer installed. - Selenoid screwed in place. - Belts in place. - Two removable black plastic parts placed on the tape transport assembly. - Battery door hinge placed on the corresponding pin on the mainboard. - Tape direction sensor on the mainboard placed in the adequate position, aligned with the slot on the tape transport. The frame and the door are a bit tricky to install: - Screw the large hinge to the door. - Place the door hinge in its slot on plastic frame. You need to figure out how. Don't force it. - Place the hinge on the chassis. - On the other side, place the door support between the chassis and the door, and screw it to the door. - Align the frame to the chassis. - If you did everything right, you should be able to close the door. Again don't force it, it should close easily. If it doesn't, don't rush. Find out what's out of place, never use force. Install the front cover: - Start from the audio jack - Mind the position of the hold button and the head ribbon cable. - The shorter screw should be on the motor side. Install the battery door cover. OTHER Tape speed adjustment control is accessible on both sides of the mainboard, so you can adjust tape speed in real time. Look carefully for it. You need to put a tape inside to test operation, otherwise it's not going to work. If it's still not working, check the position of the hold button SO, finally, what were the results on my units? Playback ticking dissapeared from both devices. No more noises. And the big question - flutter: - First device - the one with the sanded capstans, for which I had great expectations - flutter was exactly the same, unusable. - The second device - the one with the rubber bands on the capstans - played VERY well. So I didn't stop here. Since the first device had more responsive buttons on the mainboard and a better head, I took both apart again and switched the mainboard and head/pinch roller assembly . The first device (tape transport with sanded capstans) was still bad. The device second device (tape transport with rubber bands on the capstans) continued to play well with the new mainboard and head/pinch roller assembly. I finally had a perfect player. CONCLUSIONS So what is causing the bad flutter? - It's not the mainboard (switching mainboards between devices had no influence on the flutter). - It's not the pinch rollers (switching the head/pich roller assembly between devices had no influence on the flutter). - It's not cracked gears (the problem was fixed without changing gears). - It's not a design flaw related to flywheel weight or the two-belt system. - So it is (at least partially) dirt. Cleaning everything and greasing the motor and selenoid fixed both the flutter and the nasty sounds during playback on one unit. - Finally, I think it's a loss of pressure between pinch rollers and capstans. The pinch rollers aren't spring loaded, they are free to move up and down, and are pressed on the capstans by sliding plastic pins. The pins are located on a lever in the chassis, while the rollers are located on the hinged head assembly. Therefore there are a lot of wear points that can lead to insufficient pressure between rollers and capstans. In my, case the transport having capstans with rubber bands worked, while the one having sanded capstans did not, but I don't not know my units' history and wear. All later models seem to have the rubber bands on the capstans, so it's plausible that this modification, and maybe some other less visible change, were made to increase pinch roller pressure, but that we'll never know for sure. Some final words to wrap it up. I see these models gets a lot of hate. They're not easy to work on, some worn units most likely can't be fixed, therefore they're really not aging very well. But if you have a working mainboard, I encourage you to get some cheap non-working units until you get a good tape transport. It's actually pretty simple and robust for such a compact device. I probably desoldered the mainboard 10 times and it still looks like new. I restored and own several players including some high-end ones, yet this small Panasonic is my daily driver. I like the sound a lot. Even though the specified frequency range is narrower than others, I find the mids and highs incredibly better, and the bass better balanced. It can also drive higher impedance headphones. It's missing some features such as skip blanks or single song repeat, but it has autoreverse and it can skip songs. Design-wise I find the shape, size, weight and button placement just perfect. Cheers all SX owners, Don't lose faith Daniel Later edit: added some more detailed thoughts to the conclusions.
Thanks for the detailed and insightful post Daniel, I certainly appreciate your enthusiasm for these models. Let me kinda rift off your post and offer my own insights here to what you've said. First off, no one here truly hates the SX series as you have said. I think from our comments, it is clear we were frustrated immensely by our repair results because we (secretly) admire them so much. It's hard to hate them because of how sleek and cool they are... and it's rough when you love something and try with diligence to fix it only to have it sound so rough. That's where the frustration stems from... Second, I think the 'conclusions' part of your post is mostly only applicable to your units and to your experiences... it's not a smoking gun that for sure applies to everyone who has one. Maybe you didn't have cracked gears, but others (including me) sure have. Maybe your pinch rollers were fine, but others may not be. Be that as it may, I believe your process has revealed some areas we have overlooked previously. Case in point, your info on the solenoid is particularly interesting to me as I didn't do any maintenance to mine (and I recall it being less than ideal). Also, Your suggestions on where to add oil is helpful because at first glance it can be difficult to know where if you are just looking into it. Ironically, your post could not have come at a better time, I just ordered myself a NOS Panasonic RQ-SX46 from 2003 last week. When it arrives, I am going to follow your process exactly and see how far it can take me. Last, please if you could, post a video of your working unit (the one that sounds smooth)... I don't think a video of a properly working SX has ever surfaced online. It would add great credibility to your findings and give us all hope here.
Hi, and thanks for your feedback! Here's a quick and dirty video featuring the units I mentioned above. Tape speed's a little off, I'll sort that some other time. Cheers, Daniel Later edit: I've got home an did a proper audio capture from the blue SX32, using the analogue input of my pc. I'm attaching the audio capture, to serve as a reference to anyone working on these. I hope I'm not breaking any laws.
I think the capstan bearings should also be oiled, since it's a metal to metal contact, especially if the mechanism has been submerged in IPA (so any trace of original grease/oil is gone). Know the washers are not as easy to remove as the split type, but it's also something that will only be done once. As for the cause of flutter, I think there are at least 3 potential culprits: - dirt/lack of lubrication; - pinch rollers/capstans. This mechanism is designed to have low pinch roller pressure (to save energy), so any decreased grip at the roller or capstan will create slippage; The capstans with rubber bands can be restored using Lenor fabric softener. - belts; mechanism is pretty sensitive to belts, especially the one connecting the 2 flywheels;
I completely agree. I actually thought about it, but I wasn't confident I could remove the capstans without damaging them, especially the ones with the rubber bands, which I presume should be ever so slightly thicker than the shaft. Luckily they spin a little slower than the motor, and the brass bearing is self lubricating to some extent. Also, the capstan opposite to the motor can be spun and checked by hand since it's rotating freely after removing the second belt. This way, at least you have a strong indicatione if they're stuck. Cheers, Daniel
Wow, that first orange unit really sounds rough! ...and that was AFTER all the work you did to it? If you changed over the pinch rollers between them and the audio quality didn't improve, I think you can safely rule them out in this case... unless the rubber bands on the capstans really do something after all... It seems to be that the grinding/ticking matches the rhythm of the flutter... but that may or may not be true. The blue unit sounds much closer than I was able to get with my SX55/53... I'm surprised. Thanks for posting! As Valentin mentioned, it's crazy how much of a difference belts make in these. I remember swapping between a few different sets I bought on eBay and each time I would get a completely different result. Here is the SX46 I just bought (which is now in transit to be delivered early next week) Looks like it shares the same mech with your first unit (without the rubber bands on the capstan). Confidence inducing... yay. FYI, I settled on this unit because it was cheap from Japan, and I have a few Panasonic audio things from '03, and the design of this fits right in.
I don't like the SX Walkmans. The main problem is that I use my cassettes in many different devices, and oil from the capstan bearing regularly leaks from those devices onto the inside of the tape. With the SX series, they've chosen to make the pinch roller so narrow in width that the capstan pin provides all the traction on the tape. And that doesn't work if the tape is even slightly dirty inside. Resulting in a lot of wow and flutter. When it comes to Panasonic, I strongly prefer models with the AR20 mechanism, such as in the RQ-X** versions. These are much less prone to this problem in practice.
Wow that looks mint! I don't think it's the same mech. The tape compartment looks substantially different, and there is one key difference I notice - the pinch rollers of the SX46 look like they're spring loaded. The rollers on the SX32 are actually free to move up and down. After closing the door and starting playback, they are pressed on the capstans by a sliding plastic pin above them, which I think is actually the real design flaw of this transport system. The pin is on a lever in the chassis, and the rollers are obviously on the hinged head assembly, so there is a lot of wear points that can affect the pressure between rollers and capstans. Just like Valentin mentioned above, this low pressure system may be a key point of failure. I do believe your unit, being 4 years more recent in terms of design, has improved. Plus, there seems to be no actual wear. Be careful following the steps that I took, they probably don't apply. You could get away with just a belt replacement. Regards, Daniel Later edit: It actually seems that the SX46 is the only SX model ever made with the new tape transport system, before everything was discontinued in 2004. Please share your results, this could be interesting.
Indeed SX46 is an RQ-X mechanism (AR20). As for AR10, these being late models were designed for efficiency, hence the reduced roller pressure. Another important thing is takeup torque: if it's too high, tape will easily slip between roller and capstan, causing flutter. And of course rollers themselves, if the surface becomes glazed and friction is reduced, that will also contribute. In my opinion, at least the main rotating parts (motor + capstan bearings) should be cleaned and re-lubricated individually. Capstans with rubber rings can be removed without damaging them, the rubber is actually a bit thinner than the capstan. These models have 2 washers: a non-split one for oil sealing and a split one that holds the capstan. See picture attached. It is also possible to etch these capstans with ferric chloride (and it does help), just be sure to clean with water after. Never use IPA or any kind of alcohol to clean these type of capstans ! REV flywheel gear does crack, but usually doesn't split all the way through so most of the times is still usable. New ones are available.
Welp, the unit did arrive today and I got it apart and looked at: It's very clean in here. The entire belt had wrapped itself around the motor, so the pulleys and flywheels remained clean. I got lucky because my tweezers unwrapped pretty much the entire belt in one go from the motor spindle, and it only left some minor staining. Honestly, it's the luckiest I've ever gotten with melted belt. I noticed a few things about this mechanism that is very different from the others on this thread. First, this mech doesn't have a solenoid! Instead, the motor runs 'backwards' to change the transport mode, and forwards to turn the engage the tape spindles. Never seen this before. Also, the mechanism is really basic, with much lighter flywheels and less moving parts. In fact, it doesn't seem to have the problematic clutch that breaks on the earlier SX models of those brass flywheels with the cracking black plastic gear rings around the edge. I wonder if this mechanism will be any good? Anyways, I need a belt, and don't have one on hand. Just purchased one before writing this, so we'll see how it goes next week or so when it arrives. @dani7959 It's interesting that you mention Panasonic discontinuing these Walkmans in 2004, because the original owner of this mentioned he purchased this in October 2003. He also said that he bought it to replace his primary Sony unit which stopped working, but he only used it a few times as the Sony unit started working again.
Its looks very AR20 mechanism. The differences I see are that the rotary switch has been changed from mechanical to optical. The motor is also different from the standard AR20. It's likely an upgraded newer version of the mechanism. If the capstans and pinch roller design match the AR20, then this is sure to be a very nice player
Hi everyone! I've fixed a few of these RQ-SX units myself, and also agree that it can be a pain bringing these units close to factory spec. For the RQ-SX46, it uses the AR21 mechanism made in the early to mid 2000s. If I recall correctly, 3 models utilize this mechanism, RQ-SX46 (2003), RQ-SX47 (2004) and RQ-SX59 (2005). The RQ-SX59 was the last model produced by Panasonic to use this mechanism. Also, thank you @Recaptcha for posting your insight on this last logic controlled mechanism produced by Panasonic. I was scratching my head figuring out how the mech works without a solenoid. These last gasp models reduced their part count, and cut down on the amount of metal used so as to reduce manufacturing costs.
Interesting! I didn’t know Panasonic made this type of cassette player until 2005. Do you think I’m going to have an easier time repairing this mech vs the older SX ones? With all this talk, I’m rooting for this player now more than ever.
I surmise that the shrinking cassette market of that period led to manufacturers rolling out models that were catered more towards language learners. This can be seen in Sony's Walkmen models where they removed the Dolby NR feature and included speed controls. In Panasonic's case, they removed Dolby NR and kept the basic functions with the inclusion of S-XBS. In the RQ-SX59, the S-XBS button has a double function, in which a certain segment of a tape can be played repeatedly. Your unit looks close to pristine, if there are no electrical issues or if the motor didn't go bad, I'd say there's a fair chance that it can beat the older RQ-SXs. It also employs almost the same anti-rolling design commonly seen in Sony's Walkmen, so playback will be more stable compared to the AR10 mech. Repair wise, it's definitely simpler than the AR10 mech. For the AR10, you'd have to deal with a broken clutch retaining disc, the brittle gear next to the capstan driven by the motor, and the gear under the capstan which will develop micro-cracks. Maybe the most you'd have to do for this RQ-SX46 is just cleaning of the pulleys and perhaps lubrication of the motor bushing.
For sure, even compared to the previous RQ-X generation (AR20), which had a clutch retainer prohlem (and it needed to be glued), this seems to have a re-designed clutch. So despite mechanism was made cheaper (optical encoder instead of mode switch), different motor, overall it's a better design. What I would recommend doing as maintenance is clean and lubricate (watch oil) the motor and capstan bearings. SX (AR10) are together with S (AR90 - pad lifter version especially) harder to restore than AR20.
Looking at certain a certain japanese proxy service, I see quite a few SX46's for sale, which is a good indication of the reliability of these models. For example, there is not a single SX32 on sale. Now I find myself looking at prices for these. @Recaptcha I'm really looking forward to your conclusion.
And now, the moment we have all been waiting for... the new belt is in, but does it sound any good? I am pleasantly surprised! Tape speed is pretty stable (compared to my previous luck with the SX series), it has a nice full sound, it gets plenty loud enough, and all of the track select functions work as intended! Off to a good start I'd say. Both reverse play and normal play have the same levels of wow/flutter, so it's not like my past RQ-SX experiences of having one side be really wobbly, and the other not so much. I would guesstimate the flutter at about 0.3%. So the wow/flutter is far from perfect, but we are now in the realm of tolerance (for me at least). I have proper working Sony EX series Walkmans from the early 90s that sound like this as well as other 'slim strong' style players with this level of stability. Do I think it could be better? Yes! If I replaced both pinch rollers and put a charged gum stick in it, it would improve slightly I think. You guys were right I think, this is a much improved mechanism over the previous models. It doesn't have any loud ticking or rough gear sounding noises, plus it feels more composed and less sporadic (thanks to the lack of flaky solenoid). The only drawback I think is the FF/REW speed and the time it takes to switch transport modes. Running the motor backwards and then forwards and repeating this a few times to change auto reverse takes about 3sec, so it feels 'laggy'. FYI, the motor noise that can be heard during FF and REW is cancelled out in play mode before the audio amp kicks in. Even between tracks, no motor noise is heard. I'll keep playing with it and see if I can improve it even further.
It's great that it's working out so well. What they've done with the AR20 mechanism is make it a lot thinner, so it fits in the thin SX Walkmans. The clutch has been moved deeper into the mechanism. The rotation switch protrudes much less. The motor is probably also much narrower than the standard motor. I'm going to look forward to these models. The combination of the reliable and simple mechanism and the slim design of the SX line is a nice combination. I definitely want one too. If the thickness of the Walkman is less important to you, there are many nice AR20 models. They're definitely recommended for everyday use. I currently have an RQ-XF50 on the way. It also uses the AR20 and can record from radio. I'm curious to see if that's a decent player.
