First post on here, so bear with me.  

I have a great looking Aiwa HS-TX656  that does not play tapes, or FWD or reverse.  I opened it up partway and noticed the belt was off , so I tried to out it back on and of course it came out.  It was broken.  

But it seems hard to get the belt or a service manual.  So is it worth it ?  Or should I start looking for another auto-reverse, dolby walkman?  If so, what do you suggest?

Retrodos is the guy to ask about that, I think he might be able to salvage it.  I sent him an Aiwa unit a few weeks ago and it hardly played tapes as well.  Chances are, the belt needs replacement among other things.  Anyway, it's working good as new now, so I would recommend sending him a PM.

Why not? Not a desirable model but with a new belt, it's an easy fix. These are great to work on for those new to walkman repair- simple disassembly, big mechanical buttons, and sentimental value aside, no big loss if you screw up. I started out learning walkman repair with a similar walkman.

Absolutely agree with bub. The TX656 is not one of the great AIWA walkman, but nonetheless if you want to learn to repair walkman (in this case re-belting one) then it is a good test subject.

If you need a new belt, ask our resident belt supplier DocP via private message (Dialogs at the top of the window) or in his featured thread to see if he has a belt to replace it. Alternatively you can also try turntableneedles.com if you prefer.

Use a piece of non-stretchable string or wire to work out the circumference from the belt path (less about 10% to give some stretch). Don't however rely on the broken belt to get the circumference as it may have overstretched when it broke.

Having issue with belt size, the string I used came out about 9.3.  Broken belt is 9.5 inches.   But that is guessing. The belt wraps like the aiwa hs-rx703 which appears to have a similar layout of pulleys.

Given i can figure out what size is needed would a 9.3 make sense?  Or  a 9inch?  

You should go a size smaller than the string less 10% as plop mentioned is a safe bet. Get a square belt with a similar width as the original.

Thanks everyone for the help.  9". Belt worked.    

Played good in both directions at first, now pay fwd is not working.   Getting  rev side backwards.   Any ideas?   So close...

Let it reverse by itself, seems to be working now.  Weird...

Till the sides overlapped...

Screw on side of tape head, adjust there first?

If the player is playing the wrong side backwards, it is likely a mechanical issue where the autoreverse mechanism is not changing the position of the FWD/REV switch correctly, or failing to complete the autoreverse cycle. Do not touch azimuth (head screw).

Makes sense.  

Caspins flip with switch, and other wheel turns.    Not sure what else would need to happen.

Not sure on the belt.   In rwd play , it's perfect, sound and speed.   In fwd play , the caspin and drive gear switches fine.   I hear that side at a lower volume mixed in with the rwd sides's sound. Basically I hear both sides at once.  But it does switch direction.

Found it ,  reverse switch rocks when flipped to forward.   If I put back into position, it works.  Cannot see what would keep it in place.   So trying superglue...

Thanks for all the help