Greetings every ones ! This is my first post here ,i'm glad to have found such a nice forum ! Like you i'm a walkman fan , i actually own a jx849 and a jx303 , both need maintenance today... I had fixed my 303 years ago ,i had very weak sound after 4 years unused, the problem was caps of course ,i managed to change 2 of them ,but i had to use the space provided by the lead-acid battery to fit them because i had never found some small enough but i've read we could find them now , another one has seriously leaked and i'd like to change it although everything works fine now ,so i'll have to find some small caps that fit. I'll create a topic about the 303 at the time.

My problem today is the 949 , i bought this one 15 years ago new but wasn't satisfied with it so i sold it to a friend , who just gave it back to me ,know i love the sound , different from the 303 but may be better , i woulnd't beleive the fact 15 years ago... But it now has troubles... the sound is still heavy and great , but the reverse function , the rew function won't work very well , they begin but stop after 2 seconds , i've also noticed that if i simulate the tape inside , the rew function OK , i'm thinking about a belt problem. Well today i decided to open that little babe but my trouble is i 'm unable to remove the mobo although i've removed(i think) all screws. Anyone ever opened a jx849 ? I've managed to open my 303 , it's so easy ,with the 949 , the mobo won't buge ! I've checked half under the sticker in the cassette cabinet but  there was no screw there so i stopped removing the thing.Someone has a clue ? I can show a photo of it. Many thanks for your help !

I've completely removed the sticker but...absolutely now screw under ! I wonder how to open this.

I imagine the worst... would the board be soldered to what's under ? Like the motor connection wich is hard plastic part , not the flexible flat thing... I've checked for clips but i can just see one.

The HS-JX849 is based on the 0ZM tape transport, so yes you will need to de-solder the PC board from the tape mech before it can be worked on.

Since it is a recording walkman, there will be 8 solder points to desolder. Four for the motor, 2 for the playback solenoid (better hope it is not like the JX707 which melts like butter) and 2 for the record solenoid.

Thank you so much !!! So that's what i imagined , soldered motherboard ,better be sure of your work before re-soldering... Well not too many solders , i have located the motor ones , could you please indicate me the other one ? Thanks per advance.

I haven't worked on a JX849 (Sorry, but I have no desire to own one ) so I cannot comment exactly where the solenoid points are. I've tried to spot them from your photo, but there is a lot of reflection from the flash.

The later AIWAs were marked with a thin white arrow pointing to the appropriate solder blobs, so maybe there are some on this board too.

I will try to do a better photo or try to find one with google.

What's the heck with the 849 ? You don't like it but why ?

By the way , i would add to the problem list:

reverse not working as well as rew,record, going for 2 seconds then stops , no sound. Near the end of a 90 minutes tape i've noticed some distorsion in sound ,getting slower like it was hard to ride the tape...

Do you think it would be the belt only ?

I have similar machines to your JX849, but I'm not going to dig mine out. (And no, I do not think that any Aiwas from this series will sound better than a JX505).

As to why plop and others do not really want a JX849 (or any aiwa from this series) is because this is the era Aiwa started to cheapen down and no longer innovate. For example, your JX849 has a plastic flywheel, a clear symbol of cost reduction...

What you can do is:

Desolder all the flexible cables  first.

Desolder any 2 solder blobs where the solenoid is (quite close to each other). Use a torchlight. Yours seems to be near the top. Should be another for recording somewhere near the bottom.

Desolder all the blobs leading to the tape type/tab detector at the top.

Desolder the blobs on the power input jack. (Or try to unscrew)

Unscrew the headphone/mic jacks from the chassis. Sometimes you have to desolder though.

Sounds like you need a new belt as well.

@ Cosmos,

Sorry I wasn't having a personal dig at you. I just favour the older AIWA pre-100% Sony ownership models. I particularly like the ones that are based on the bi-azimuth transport of the PX303/PL303. They are easier to work on. Strangely every one that I have owned or seen have had intact belts. Which is not what can be said for the later ones: mushy belts, dubious quality control, hard to get into (desoldering PCB), non-heat resistant solenolds, generous use of plastic.

I also like the styling of the earlier AIWAs as well. But that's just my opinion.

I too prefer the older styling, before everything went "organic".

Strangely all the Aiwas I get that are made in Singapore still have great belts too. Perhaps different supplier?

That's fun how people seem to enjoy the 505 ! Well eveyone has a favourite model indeed.The sound is different depending of the model. I don't know if Aiwa wanted to reduce costs or if this was just a result of reducing size and weight ? But for sure it's not easy to work with the latest models.

@bub

Maybe. The three PC202 that I have which are all made in Singapore all have intact original belts.

My JX303 still has its original belt in good working order.

The 505 line was the zenith of all of AIWAs achievements. There wasn't any one model that was head or shoulders above the rest. Each had their strength and weakness. If you wanted maximum function, you bought a JX505. If you wanted an excellent player you bought a PX505. If you wanted a flexible miniature recorder you bought a F505. So, this is why the 505 line is so interesting for me.

 They were also what represented the top or near top of the line. The older AIWAs are very hard to find now due to a lot simply ending up in the trash probably due to failed caps and normal wear and tear. This alone makes them harder to find nowadays.

Exactly, and a lot of those models from that era still do.

There is a world between what you say about the 505 and what i experienced, you wouldn't imagine ! This is well the follower to the JX303 ?? The most important is that you're happy with it , mine was surely faulty.

By the way , this photo now talks better to me ,the answer was there...

Here's another interesting fact: I buy all my belts from stores locally, and often the stock they have is rather ancient. But they are all still good! And this is despite them being displayed in racks at the front of the shop, in the air.

About Aiwas ending up in the trash: Most of my collection is from a flea market where the source of them is mostly from discarded electronics. So many of the models we covet such as my (DC2(!), JX2000, 505, 707, WM-7, etc) were once about to be/was thrown away! There were lots of Aiwas here in Singapore and many people still remember the brand fondly. There are still some Aiwa banners on some older electronics stalls here.

Those were just the lucky ones. Here in the UK, most shops will not accept 2nd hand electronics goods for fear of being sued by the buyer. These if not sold privately such as in car boots or ebay would just be tossed into the bin!

Would you use an hotair station to remove the board ? I'm not sure since it's very thin and there are surely components at the bottom(they could drop...) , the flexible cable is near and some plastic parts near some soldering points too.

Personally I use a regular 45W soldering iron with a regulated thermostat set at the lowest temperature to allow the solder to melt. Be aware that oxidised joints will be harder to melt. A hot air station with a pencil tip would be useful for complete part removal of SMD components especially ICs, but you need to be sure to mask off the plastic parts on these PC boards to prevent them from melting.

Sure,thanks! I think i will remove most of the solder part with my iron and may be the final extraction of the board with the help of hot air. I know how hard oxydised solder is sometimes hard to melt.

The little beast is now opened !

Let's see what we have here:

All caps surface mounted , aluminium.

3x 220 uF 4v diam 6 mm

2x 100 uF 4v diam 5 mm

3x 47 uF 4v diam 4 mm

The belt seems fine but will be changed.Now , is it the belt or the caps ? Hard to know unless the bord is soldered again... and it's hard to remove....

Ok , the belt ! Once taken off i better see how sick it is. It's very thin.

Old belt measure 9,2 cm (flat so x2 if you cut it) in 0,8 mm.

I've finally used only iron+desoldering pump.

This mechanism is very popular in mid 90s Aiwas- I have several with this mechanism. Sadly yours is a version with a plastic flywheel- mine are all brass.

On the plus side, very easy to change the caps, and one of my examples, PX347, actually sounds rather good after a cap change. Sadly the rest of my collection with this mechanism does not sound that great...

Hey! Received my second one from Thailand ! Seems to have the belt problem too ,but this was in the ebay description so no surprise , oh my what a sound again,i love this JX-849,i'm sure it'd beat the 505 !!!

Now i'm wondering , opening this is very hazardous ,and i'll have to re-open surely in the future ,whether for belt , may be caps or regreasing , any idea for the soldering points ,should i try something like small wires instead resoldering ?

Not sure about the small wires, but I agree regarding the soldering aspect. I hate servicing walkman be they AIWA, Sony or Panasonic and you are required to get the soldering iron out to just replace a belt. There is an element of risk that you'd encounter problems when trying to separate the PC board from the tape transport.

Best to minimise the number of times you need to gain access to those parts if you ask me.

I've worked on enough of these guys that I can assure it it's quite safe to do it over and over again, as long as you are careful. I find them relatively simple.

One common fault of this Aiwa series I feel is inefficient pinch roller design- if your pinch roller is even slightly worn/out of spec the unit will have trouble playing from the leader, and with this brings problems running in one direction, or auto-reverse problems.

@Bub

Regarding the pinch rollers. Last night I discovered that the pinch rollers on a 0ZM tape transport can be easily removed. This can help facilitate easier cleaning.

Using a blunt metal object roughly the same diameter of the pinch roller shaft, it is possible to push the shaft out. If the shaft fails to come out in one direction, pushing it through in the opposite direction and it will come out. Allowing the removal of the actual roller itself.

Also I discovered that for two of my JX707, that were giving me playback issues. They both had damaged tape guides on the plastic housing of the pinch rollers. Luckily I have spares from junked units to repair these both.

I think the damaged tape guides on the 707 must be very common then. I was surprised to discover the tape guide also broken on my JX70.  It's a real shame as mine has to sit in a corner until another one pops up locally, and even then I will still need the battery holder. I think they likely broke when the tape is not inserted all the way and the lid is forced closed.

I sometimes switch out pinch rollers/heads between units, but if at all possible I just swap out the whole pinch roller assembly, although I also use the shaft method you mentioned, especially for my WM-EX1 series.

Hi plop,

Could you perhaps explain with a picture, how you pushed out the pinch roller? I have an AIWA with a lot of wow and flutter, maybe a changed roller can help in this case.

Belt changed and all functions back OK !

Now i must look at my second unit wich has the same issue,i've also noticed a unaccurate tape speed ,don't know if it's due to the belt or the previous owner...

Aiwa made great stuff in the day. If i remember right sony bought them out and then they went down hill fast. Sony didn't want the aiwa brand around.

Since i wasn't fully satisfied with only a new belt ,having little flutter ,i decided to open the unit again , to regrease has much as possible ,i've used watch grease and sewing machine grease(very few as it's liquid) ,i also decided to recap it all (photos coming soon) , after resoldering the board , flutter disapeared(new caps or grease i don't know..) but new problem occured ,the rew function now is very slow , in fact the unit playback in rear ! The fastfoward function is OK.I can't remember is the rew problem was there after changing the belt.All i remember is with the old belt , the tape wouldn't move at all (pb,rec,rew,ff..). I've opened the unit again and again(i'm used to now!) trying to fix this but i've no clue.I've though about a cap badly soldered , but i really don't think since you follow the location well.What is working with new caps ,almost everything exepted the rew function(and same in reverse mode) , it "plays"(no sound) instead of rewinding fast.So i'm wondering , a shortcircuit for one or more caps and the player wouldn't work quite so well ? Of course in the multiple times soldering/unsoldering most of the tape detectors pads have gone but i managed to do the connection again with small wired(thanks my old dead J08 i had kept all the small wires). Now i guess it may be a gear problem or something ! It's really a nightmare to have to unsolder/solder again & again to check the results each time ! I will really have to find a solution with small wires to keep the unit opened to see the inside , and close it really when the job is finished ,that's my advice.

Well , the rew functions happened to work say 3 times between 20 tries ,it seems to be weak but it worked ,most of the time it acts as the music search ,music search has no sound right ? And i figured too that in the reverse mode things would...reverse ! In this mode the rew function is OK and fast , and FF act as the music search... So isn't it clearly a mechanical issue ? I don't think it's a button problem since it would the issue also come in the reverse mode but with the opposite button(ok?).Could it be a greasing problem ? I don't think so now ,why would it be fast and strong in forward mode and weak and low in reverse mode ? I bet something is too used somewhere. How many aiwa i hear the same problem with reverse mode ? My other JX849 works fine in forward mode but has problem in reverse mode.Any idea ? By the way you can found(sometimes) very thin wires in PC mouses cables.

Hey hey ! Look : 

http://www.crystalradio.cn/bbs...hread.php?tid=104829

So close... so same ! I wonder why they are pointing that little thing ??? Someone who read chinese here ?

I've never broke a trace on any 849 series Aiwas even though I was really crap at soldering at the time. I found the board rather tough (although the even later Aiwa series were VERY weak).

You can use small wires to work on the unit when open but do not leave them in the unit when you are done, or you can have erratic logic.

As for the logic controls going nuts- welcome to one of the worse logic controlled designs Aiwa made. If your pinch roller is not perfect the unit will not play in a certain direction, if your FWD/REV switch is dirty it will not go in one direction, and sometimes when you press REW/FF the unit plays instead... It's not a cap problem. It's just that the tolerances for this Aiwa series is very low- any small thing out of order and you can't get it to work properly. To put this in perspective only 2! of all the 849s series I have work with fully working logic and no Wow and Flutter.

Do not forget that when you re-solder the unit, The logic cam and arm must be set to the default position, or the logic reset may not work properly.

I can read chinese. Interesting fact- The "Ai" in chinese stands for love. "Wa" Stand for Chinese. So Aiwa literally translates to "Love Chinese/China".

That Chinese guy was having problems with the logic too, and figures that it is a problem of the cam spring lever. Personally I do not think that is the cause, as long as the cam mechanism is oiled properly. He probably does not know that in order for logic to reset properly, the logic cam and arm must be set to the default position.

Oh and one more thing- check if your solenoid works properly. If your solenoid is dead the unit may not reset correctly and will not REW/FF properly or play in a certain direction (Although one of my units with an ok Solenoid will not REW properly anyway). If the solenoid is dead the unit will still play, but in one direction only.

The correct reset position is on the side of the cam gear where there is a concave portion with no teeth. You can refer to one of my photos in the Mid 90s Aiwa thread- that is in the correct position.

If the FWD/REV switch is dirty all functions will work except either FWD/REV playback. On my PX347 for example, I could not go into REV mode until I replaced the switch with a spare. It would go into REV for 1 second, stop and reset.

Thank you so much for those nice infos ! Oh my ,i wouldn't have imagined i had to leave the mechanics in reset position ,i'm afraid i've turned manually things before closing.... You're lucky you didn't broke any traces ,yet with wires you can manage ok.The pinch rollers seems fine ,it plays well in both direction ,so may be a dirty button but i doubt ,because the problem "reverse" when you..reverse ,so more something to see with the gears not in reset position or a dead solenoid ,yet my solenoids seems fine since they both "catch" their "goal".I will try to look at the gear without desoldering and see if it's in the reset position ,can you look at my photo ,do you remember if it is the right position ? It should but just to be sure...

Talking about the 849s series wich i would say shares only the same mechanics , look at those photos in my link(JX869) ,no more caps ??? How does sound compare with a JX849 ? I'm looking for one but these seems hard to fing ,i don't know if these were even sold outside Asia , do you know ? 

Some later Aiwa and Sony machines are redrafted and redesigned to use Tantalums. Sound quality on most tantalum units I find is rather good, especially the Sony EX-1 series.

That model number may be asian only, a similar model may be sold under a different name elsewhere.

Yes you need to set your Aiwa's cam in reset mode, as seen in my other thread. Although not always required, I find that sometimes the unit will not reset correctly otherwise. Only seems to apply for this series, although I do this for all logic controlled machines. I remember reading about this in a service manual as well.

You can tell that the solenoids work if FF and REW both work at full speed. It is  harder to check the FWD/REV switch, but if all other functions work fine except playback in a certain direction the switch is dead: the unit will play for one second, stop, and reset.

However, judging from your previous posts, has nothing to do with the buttons. Your solenoid is likely dead. You can swap boards between your 2 units to check.

If you hate resoldering over and over, I recommend using VERY LITTLE solder, just enough to bridge the connections you need. Then you can just apply a small amount of heat and lift the board off carefully.

What is a dead solenoid please ? How would act a dead or alive solenoid ? The forward and reverse playback modes are OK. Anyway to check the solenoid without desoldering again ? I have a multi tester ,could it help checking ?

I suppose the only problem then is that your machine will not FF/REW properly?

If that is the case you can remove the lid of the tape deck and check to see if the pinch roller touches the capstan on REW/FF. Then press DIR (stop or repeat) to change the unit to REV mode, and check both REW/FF again, and see if the opposite pinch roller does the same. If so, you very likely have a problem with the solenoid or the logic cam mechanism.

A solenoid is essentially a long coil of wire. So one test would be to test that the binding posts are connected to the winding wire with the continuity tester on your multimeter. The other test involves checking whether there is a short across the winding wire preventing the electromagnet to energise, one way would be to get a similar known good solenoid and comparing the resistance of the good and the questionable solenoid's values.

Alternatively you could just apply DC electricity (probably no more than 3V in the case of these walkman types) and the solenoid should energise the electromagnet.

Thank you , that's what i was thinking about , a continuity test.I repeat , in forward mode , it won't rew correctly ,in fact the thing push head and pinch roller so it likely "plays" in reverse mode(but no sound and the screen displays well "rew") ,finally nothing to do with a music search mode wich i suppose is fast.That's for the forward play mode. On the reverse playback mode , things would do the same on the opposite side ,in this mode , rew is ok and fast when ff is slow and the head and pinch roller touch the tape.It's like it wouldn't declutch or something ,when the function works you can feel a "ting" in your hand ,and i as i told you ,sometimes the rew function would work(but rarely)then with the "ting" thing so in forward mode but when it works you can hear how hard it is to rew compared to how easy it would ff. So i don't know if a dead(or alive) solenoid is related to that fact ? I suppose that with a dead solenoid the reverse (or playback) function wouldn't work at all ? To me it's likely an old dry grease that act as a brake somewhere but specially on the reverse gears , as it seems to be made ,it's likely the forward function is quite "direct" since the reverse function is an amount of gears ,do you agree with this ?

edit:same thing for the music search in "rew" mode , it's slow albeit it finds well the begin of the track , search is mode in "ff" is fast...

Please tell me ,is this the right reset position ? This is your photo:

http://REPLACEMENT ERROR/fileS...lineImage/true/5.JPG

edit: Ok both solenoid gave a 052 value with continuity test ,default value is 001 and when no contact is 1 ,seems good !

I'm now trying to see the default position...

The strange thing is that on your photo your solenoid is "closed" while mine is "opened" ,it's actually on the reset position and it's opened , on the picture below (the fist time i opened it ,when it would always come to reset position) it's opened too ! So who's right ??

LINK ERROR.3007832099276/page/1

That's why i wonder if i need to desolder again :bored*100: to check this... When you regrease , do you take it all apart ?

From what i can see , the small thing the chinese guy is pointing is like you in the upper position.

Now something i'd like you to check if you can of course , just removing the back cover ,could you look to what happened in rew and fast mode ,in forward mode , when i ff the arm won't move but when i rew the arm goes to the left and then push the head and pinch roller up ,is that a normal behaviour ? I suppose no but... I can also that it switches the small switch(to the left) to the left , and all the same in the reverse playback but the opposite... From what i can see the reset position seems to be fine yet i'm not sure.

I have a unit that sometimes does the exact same as what you said. It is not a gearing grease problem. It is very likely a solenoid issue/cam mechanism. Goes along the line as:

To go into FWD playback from FWD mode, no solenoid action is required. No solenoid action is required to go into REW mode from here. However, solenoid action is required to go into FF mode.

In REV mode, FF and REW swap places so... to go into REV playback from REV mode, Solenoid action is required. No solenoid action is required to go into (now FF) REW mode from here, but Solenoid action is required to go into (Now REW) FF.

Simply put, with the problems described the unit has trouble going into REW (or FF in REV mode), which DOES NOT require solenoid action. Which means that solenoid power is being wrongly supplied, OR the cam is malfunctioning, OR perhaps it could be the switch that lets the unit know if it is in mute (FF/REW) or playback (FWD/REV) mode.

Bloody confusing, isn't it?

Now, I have not got around to properly fixing this unit, and after quite a bit or parts swapping, board swapping, and switch testing, cannot properly confirm if it is a board or mechanical issue.

However, the 3 main areas are still: solenoid, cam mech, switches. If you could fix it, let me know your solution- my current solution is lightly slap the thing if it refuses to work.

Edit: My photo is correct. Solenoid position does not matter. And has got nothing to do with music search.

In other words: unsolvable... I'd better live with it.

Personally I'd just leave it aside and use something else. Eventually, you can cannibalize it for parts when you get a better one.

My PX347's logic worked terribly until I eventually got parts from others to create a perfect working machine.

(If you want another area to check, try cleaning the board)

By the way , a short circuit in the caps(one or more) and the unit would surely complaint isn't it ?

Caps normally relate to the amp circuit, but I do know that if there is a short in those along the power line, the unit may not power up.

I would agree with bub here. If your PCB has the slightest contamination, it can screw with the logic control. You will either have to perform meticulous cleaning or write the board off as unusable, until the problem causing the erratic behaviour can be located. I have had issues with erratic logic control on a number of AIWA, and in the end it was due to contamination.