New Member from SE U.S.

Hi Everyone,

I'm new to the forum and I have a number of personal walk-person type recorders (I prefer recorders to playback only devices, although I don't really mind the FM option in cassette machines) and I've recently acquired two TCS-430's and a nearly nib appearing Aiwa HS-JS415 and I've owned a second Aiwa HS-JS415 for about 27 years, and it has worked flawlessly-SO FAR.

The new 415 isn't so lucky. I opened it up and the belt had liquified and had already been removed. The good news is the motor appears to work fine. The second belt also appears to be in good shape. I'm waiting on belts to arrive, but I was outright shocked at what's happened to the price of them.

My question regarding the Aiwa is what are the dimensions of the main drive belt. I know it very likely is very small in diameter. (.7 mil?) I also don't know what length to order. I'd be fine to order a selection of them, if I knew that in so doing I'd get the belt I actually NEED in that order.

On to the second question, this one about the TCS-430.

I briefly got it back to working GREAT (I had to realign the heads, nbd there) and adjust the downward pressure on the cassette (no nbd there either) but before too long (and after the clean-up most of which was accomplished with goo-gone and 91% alcohol) it started having significant W&F issues. It never (here comes the wind-up, I didn't know this until I started scouring the Internet, but I read that they nearly all lose their fast wind functions) was able to fast wind in either direction. I DID get it to fast wind for a short time before it stopped in the middle of the restoration. I put a generic belt (I repair electronics in my retirement, but both Covid supply chain crisis and my post cataract surgery are proving to cause both new issues and correcting previous deficits) on it and it played fine for some time.

So there are multiple symptoms now.

1. W&F issues are interspersed with the unit wanting to play too fast. I'm pretty sure there is insufficient pinch roller pressure, but the service manual doesn't say how to adjust it or IF it can be adjusted. So any advice about that would be very much appreciated.

2. It appears to me (judging by the drawing in the SM) that there is an entire/gear pulley MISSING. Which makes the player momentarily being able to FF/RW a little bit of a symptomatic "X-File".

That's it, so far. Any appreciation by the experienced pros here would be very greatly appreciated.

Thanks in Advance!

 

Hello, and welcome!

The TCS-430 and other units with the same mechanism does have a weak spot on the friction clutch driving the spindles on FF & REW mode.

Just below the brass capstan flywheel, there's a sandwich of 2 light grey gears that forms a friction clutch. Pressure is exerted on them by a spring on top, pushing against a plastic washer and locked in place by one of those thin flexible locking washer. Under constant pressure, over time these frequently fail, leading to a loss of friction and loss of FF/REW functions. They're also prone to go missing after failure, as the parts are spring loaded and very small. It's very easy for them to come off an disappear during disassembly, especially if one is not expecting it.

Without seeing some pictures, I have some guesses regarding your FF/REW issues:

1. The part was intact at first, then, triggered by movement from the now working walkman, it failed. And perhaps went missing without you noticing it. (You mentioned that there indeed seems to be missing part, but didn't mention which one. The gear itself is large, so it wouldn't go missing "silently")

2. It was missing to begin with and the clutch has been modified by someone before. In the first place, the placement of this clutch is, in my opinion, rather unusual. Sony installed a friction cluth between the motor and FF/REW gears, where the usually isn't one. It does relief the motor of extra loads when the end of the tape is reached, but I can't remember from the top of my head of any other tape transport mechanism that utilizes a friction clutch there, I'd like to hear more opinions on this from other members... That being said, your unit should technically work without the clutch, so someone before may have glued the 2 gears together. If the glue failed after you started using it, that may explain the issue.

3. I'm quite sure this one's not the issue based on the symptoms described, but the FF/REW gear on the spindle itself is also prone to cracking. Depending on the size of the crack, it may affect the ability to FF. In some cases this may go missing as well, but if that's the case, it probably wouldn't play tapes.

All in all, the FF/REW issue should be easy to diagnose, some pics would greatly help. The drive system goes like this:
- Motor turns flywheel via the belt
- Small gear attached to bottom the flywheel rotates the top spindle clutch gear
- Top clutch gear transfer rotation to the lower clutch gear via a clutch disc
- Lower clutch gear turns either the take-up spindle gear directly for FF or the supply spindle gear via the very big white plastic gear for REW

---

As for the your issue regarding the speed and W+F, I'm not sure what the issue is. Usually the play idler may lose friction and cause problems, but that wouldn't result in it playing too fast. It does indeed seem like a pinch roller issue, so that would the the first thing to check.

Like most walkman mechanisms, the pinch roller pressure isn't meant to be adjustable, but on this mechanism, it actually kinda is. Here the pinch roller pressure is not provided by a separate spring like most, but the roller housing itself is the spring. It's made of a flexible thin sheet of metal, and on the top part there's a long section that's pulled down to act as a spring. You can adjust the bend of this section to make adjustments in pressure. This should be done with caution and I don't really recommend it. The metal's very thin, one must be careful not to improperly bend it. I'd imagine that bending it the wrong way may cause alignment issues later on, and it's sort of like an irreversible action.

 

First, thank you for your quick reply!

I see what you mean. I managed to access the PR and discovered what you're talking about. I fixed that problem and in so doing discovered the REAL culprit (not even mentioned yet) w/respect to this 430. Some oaf (not me, I promise, I may be an inexperienced oaf when it comes to walkperson repair, but I'm not that wantonly violent and it did this right out the box) had torn (and broken the board at the speaker) the ribbon that connects the power to the rest of the player. Out of the box, it sometimes it would have power, and sometimes it wouldn't. Now I know why. The board break is between traces, so that's not a deal breaker, but I'm pretty sure I don't have the gear or the skill to repair the two TORN traces on that ribbon cable. I have another (I didn't pay much for this one, but I paid even less for the other one-but if I add the two together, dollar cost averaging isn't likely to save me...I guess I can emotionally write it off as a "retirement education/entertainment expense") on the way and this might make a decent parts donor. It had internal rust, so it's led a REALLY rough life before I tried to rehabilitate it. The gears are all solid and none are cracked. It does appear that there's a missing C/E clip on the gear you mentioned. I think the spring (which I have) was holding it down anyway. But there is a "hole" between the brass pulley and the motor pulley with a conspicuous absence of anything in it where there is a pulley indicated in the SM drawing. I may be spoiled by some vintage SM's, but this one is pretty lean on text. Real, seasoned professional service people might not have cared, but I need all the help I can get. I studied electronics in the '80's but never used it in my career, just avocationally. I have an experience deficit that I try to offset by keeping that deficit front of mind before I turn a screw. I've been told by friends I'm a little too trepidatious when it comes to this stuff. I typically reply that since I'm not on the clock or on production, that's the only real advantage I can employ if I take brute forcing alternatives like just buying one at multiples of retail that have been serviced or other hyper-inflated options off the table. I have a portable digital recorder (and two parts D8 DAT recorders, now that I think about it), so the appeal is the thrill of the repair, if I have the chops to pull it off. Is there a gear missing? It looks like it to me, but I can't find any photographs against which to draw a comparison. Thanks, again!

 

Ah, it's good that the issue was found. Fixing is always fun, though finding that someone has been inside before and that they did a messy job is always rather annoying...

 

Thanks, once more Stuck-in-time. If I have the chance, I'll post a photo of the RIP 430 and update everyone on the rebeltng of the HS-JS415.

Any words of cautionary advice regarding the replacement of that second belt would also be kindly appreciated. I may as well do them both while I'm in it...Best to all!

 

Any advice on where to buy these HS-JS415 belts? I didn't get any feedback on that and ePrey's seller isn't shipping or answering emails. I have about 72 hours before I have to get on the return/refund gerbil wheel.

 

Thank you, Mister X! I'm on it.
I'll check the UK vendor first, although I'm across the proverbial pond.

 

I believe I found the vendor on eBay (a different eBay vendor than the one I previously referenced). It's annoying the sponsoring vendor didn't show up in the initial search.

Thanks!