Hello good people! I'll try to keep this as brief and clear as possible since i've been dealing with it for a while and i feel like i'd become too confusing otherwise; I recently picked up 2 SONY TCS-470 to get into the hobby (also thanks to a post on this site!), one was sold as functional (i'll refer to as A) if in need of a little servicing and the other as a bonus donor unit (i'll call B), B had difficulties FW, RW, and PLAYing both directions, while A PLAYed fine, FW and RW struggled a bit depending on which spindle had the most tape, after about a week of use A died overnight, buzzing but no Spindle movement, i opened up both and found some goo in A (belt remnant, i assumed) So after some research i ordered a new Idler Tire and a Belt from fixyouraudio, cleaned the parts with alcohol and waited; the parts have now arrived, and we come to my current conundrum. A (using new belt) FWs and RWs just fine, the mechanism spins just fine when no buttons are pressed, but the moment i engage the PLAY button, the center gear slows to nothing, and eventually, it clicks and disengages PLAY, if i hold PLAY down, it goes into an auto-reverse loop. (Guts pictured below) B (using old A belt, which isnt actually visibly damaged aside from a little stretching, so i am out of ideas for what the goo was.) cant do anything, buttons engage, but (what i think) is the shut-off gear (161 in the manual) gets stuck when any buttons are engaged (FW, RW, PLAY), when no buttons are engaged, it sometimes seizes but otherwise works if given a small nudge and the mechanism spins. I'm a "repair or craft your own" kind of guy, with tech too, but these repair have taken quite some time away from a couple of weekends already and i'm becoming burnt out on them, especially given how there is no free service manual available online (the one pictured above is from the WM-55, which seems to share most of its guts with) and the mechanism, while fascinating and quite gorgeous, is very delicate and rare. I am very close to just handing them to a shop and making it their problem, i thought it may be the idler tire, but it doesnt look damaged and it doesnt seem to do any abnormal resistance, i think that the problem must be that something somewhere is putting up too much resistance (for both of them) but i'm honestly out of mental stamina on this one; if anyone has anything to add that might help fix even one of them, i'd be overjoyed! Thank you for your time reading this, and thank you for any tips!
I see a few switches on the board. It's just a suggestion, but have you checked if they're aligned with the mechanism when you put the board back on? I'm not familiar with this model, but the effect of misaligning these kinds of switches can sometimes be quite surprising.
I left them as they were when i took the cover off, I can try to to flip them here and there but i think the issue is purely mechanical, i am powering the motor straight from its cables bypassing the board, i also desoldered B's board and have been testing without putting the board back on
It's not unusual for the switches to interact with the mechanism. For example, the motor makes certain movements to activate certain functions within the mechanism. This is especially true for an auto-reverse Walkman.
These are the only 2 switches on the board i dont know the purpose of: I can try....flipping them one way or the other, close it up and try again, maybe it really just an issue of motor control through the board, however, i really want to try to find a mechanical issue first, maybe a part somewhere needs to be lubricated as the issues have stayed consistent at every stage of assembly and disassembly, actually closing them up requires soldering a bunch of stuff so i'd like to stress the materials as little as possible. I already changed the belt, and the idler looks fine, is there any other part that commonly needs servicing, maybe one of the gears? Should i just spray the whole thing in silicone lube? I'm getting desperate XD
The last thing that will work is to just spray it with silicone spray. Lubrication is hardly necessary in such a mechanism. It often just causes everything to stick together unintentionally and slip in the wrong places. But I understand your frustration completely I am very familiar with it myself There are those two normal switches (S301, s302), and I also see two leaf switches (S305, S601). One is probably for on/off. But that leaves the other one, which also has to do something. I really don't rule out that they are necessary for proper operation. Perhaps someone else who DOES have experience with this mechanism can help.
After tea, a camomile, and a light dose of horse sedatives i have taken a calm look at the board, and by God you might just be right, S302 is labeled "FW-RW" on one of the 2 boards, by a quick scan alone, i think it gets flicked by a moving part in the mechanism, i still dont know how to explain the other switches, the mystery goo, the sudden spindle death, FW and RW being suddenly fixed, but i'll trust the Japanese engineering and the knowledge of people smarter and more experienced than me; i'll close A and report back. I wish i could find some material or someone experienced with this honestly, from what i've managed to dig up this thing's basically a hidden walkman model that only a couple people really know, the post that convinced me to grab my one is actually on the same site, maybe the user is still active and i can try to see if they might have an answer; in the meanwhile, i've got a couple vids that show the issues i'm having, what's the etiquette on video-sharing here?
After some more investigation and testing with your switches lead, i discovered that the leaf switches are POWER (which after observation, is pressed on by a lever when PLAY, FW and RW are pressed) and PAUSE respectively, putting the board back on and testing with batteries produced inconsistent results, however, operating via original psu did give some interesting results: FW and RW seem to be fixed, they struggle a bit but not more than i am expecting out of a disassembled unit, however, PLAY doesnt happen at all, not even motor buzz, the spindle jolts but stays seized, after a second a "CLICK" is audible and the mechanism disengages PLAY, which i think is the emergency stop; furthermore, if i manually press STOP, the capstans and pinch rollers will roll at normal speed on their own for a couple seconds. I am honestly baffled, i'm not sure what to make of these hints, the rollers and caps getting triggered when they do is confusing as they dont spin when PLAY is engaged, FW, RW, capstans and pinch rollers working fine suggest that the issue is unique to the PLAY mechanism path, downstream of where the mechanism splits off from the FW/RW path the apparent emergency stop (which i seem to read is triggered by overwhelming resistance) would reinforce that; however, the initial jolt paired with the lack of a motor buzz suggests an electrical issue, but the working conditions of the motor rule itself out, batteries vs psu result difference suggests power feed troubles, if i had to cast a guess, something, somewhere, in the circuitry isnt directing electricity to the motor when PLAY is engaged, i dont think its a corroded POWER leaf switch as that would cut FW and RW out too, i dont think its a dead capacitor, as i would guess those are responsible for the initial jolt i see the spindles make, so...maybe a cold solder point? A non-perceptible crack somewhere? I'm not sure, if its mechanical, the emergency stop would have to be triggered by lack of movement rather than resistance. Are these symptoms common with some other failing part? Should i try swapping A's board with B's? Could be worth a try, they arent identical, but its still the same model, all visible differences i can see are a couple of traces and 2 bridged points? There is a (Japanese) service manual on sale for 6.99, i feel like getting a clear look at the circuitry via that may be helpful
I think getting the service manual is a great idea. That way, repairs are much easier, because you can check if everything is properly assembled as intended by the manufacturer, without having to fully understand the device's operation yourself. The fact that a service manual is available already makes it a cool device I would choose the English version tho, unless you can read Japanese. The text often contains important instructions and procedures. With the service manual at hand, there's a good chance you'll be able to get it working again. https://www.analogalley.com/osccart/product_info.php?manufacturers_id=63&products_id=1771
I come bearing great news! I ended up lightening my wallet for that manual, and while its less clear than i'd have liked, i think i now have identified where the fault lies and how the mechanism works as a whole: When PLAYing, the Center gear leans on either S1 or S2, which are responsible for the spindles, the motor turns on and the belt spins F (orange) counter-clockwise, a smooth part of the flywheel spins the idler underneath (responsible for capstans, green dotted line) which in turn spins the "Mid" assembly, this both interacts with the shut-off lever (part of the blue grouping) and with the C gear, which spins either the left or right spindle. The belt then spins the 2nd F (blue), which governs the assembly responsible for auto-reverse and emergency shut-off, but it isnt really relevant so i wont exposition dump. When FW and RWing, its very subtle and hard to see, but the idler tire actually disengages both Mid and F (orange), the FW/RW arm swings forward, interlocking with Mid and F, and THIS path works perfectly; F transfers to FW/RW, which transfers to Mid which transfers to C which transfers to either spindle gear path. When PLAYing this arm is disengaged, seemingly relying on the idler to transfer motion from F to Mid, while manually spinning F, i can actually see an initial jolt being transferred from F all the way to S1/2. The weird part is that when i spin S2/S1 manually, the motion actually does travel back the whole path, spinning F with what looks like normal efficiency; while when i spin F manually, no motion is transferred DOWN the mechanism to the idler, Mid, C or S1/2 I am 99.99% sure the problem is between the smooth part of the flywheel and the idler, although i wont be sure until i get the flywheel off, which needs to be done by...removing the cassette bay door, the faceplate, and then removing the washer and retaining ring. However this is absolutely awesome as it means i am not in the "figure out how it ticks" phase anymore Thank you for your help and sorry if i got too technical here and there XD i understand you dont have much experience or interest with this model, but i'm hoping to leave this thread behind as useful info for anyone that might run into the same problem with this model, or is looking for any info on this model at all as it seems that its very hard to come by, thank you for your help again! I'll try to keep the thread updated with any meaningful discoveries/fixes (especially if i manage to fix it)
Haven't read too much into your issues but looking at the title and your mechanism which is the same as the wm-f77 (SM on hifiengine), you will need to remove the flywheel and thoroughly clean the idler wheel and flywheel with 90% IPA and a micro fiber cloth to solve the spindles not engaging. Very common issue with this mechanism but fixable
Thank you for the tip! This has been revealed to be mostly true, however, do have any idea on how to take the actual spindle head off? I've been cleaning everything and there's some resistance in there i'd like to get rid of, however the service manual just shows them as whole assemblies and doesnt show a way to get to the actual shaft
The gear on the left spindle (with the black gear) is very likely cracked. It's held in by tension so you can pull the spindle off the gear and it'll come right off.
My bad, i've been looking at it for so long i've forgotten other people dont know what i mean, by "left one" i mean the one on the top in the pictures, white gear, connected to the counter; i've nailed down the issues in both systems too the mystery goo and assorted dirt, nothing seems cracked; i've taken out almost all components of the PLAY path and thoroughly cleaned them, PLAY actually works now! (At least mechanically) but now, sometimes, when spinning the "left" spindle as i mentioned, i can hear the mechanism struggle and it eventually triggers the emergency stop, i've managed to loosen them a little bit while (desperately) basically washing the rest of the mechanics in IPA to get rid of various dirt that was causing other smaller, assorted problems. But yeah, if there's a way to take it off to clean it properly, that'd be cool
huh that's strange. That part of the mechanism differs from the f77 since there is no counter and therefore no need for a belt to attach to that white gear. Does the mechanism not sometimes shut off in reverse (both directions)? If you upload a video (or a yt link) it might help for someone to look at it. If there are no cracks and the s1, c and s2 gear assemblies move freely like you said, the auto shutoff must be caused by the idler slipping
I went to take a video after the IPA dried but the early shutoff didn't happen this time; if i understand the mechanism right: The default position is S2 as the tape plays, it then reverses to S1 after S2 ceases spin; after, whenever S2 ceases spin, PLAY disengages altogether, its not an emergency stop, its a planned stop that is triggered after the supposed side B has stopped playing. If i understand what happened with my units right, they just got gunk'd and goo'd so much in various points in the PLAY assembly that the idler and flywheel kept slipping because of all the resistance downstream; however, they are now...fixed, supposedly. I'll inspect them one more time tomorrow and make sure it wasnt just a lucky moment or something; if not, i suppose they'd be fixed! That said, if they are fixed, i'd like to make a post with all the info i found put in a clear concise and guide-like way for whoever might come looking for it, what's forum etiquette here? Should i make it at the end of this thread, or make a new one specifically for it?
Whether it auto-stops or not depends on the play mode which this mechanism should have a switch for. If it works then it works People with similar problem will find the post by title no need to do anything.
