Tascam 234 tape drive problem

[kgf]

My Tascam 234 has been out of use for a long time and when I set it up last night I had a problem with these two symptoms:

A noise emanating from the tape drive area.

When I hit play, the tape fast forwards with the heads engaged (I can see the meters moving and hear the music). Fast forward (and rewind) works fine. Play does not move as fast as FF, but it's way too fast.

The deck is nearly 20 years old and I can't whine about losing it because of it's value, but I have a lot of tapes that I can't access now. Any suggestions other than take it to a Tascam repair center? I might end up doing that, but on Tascam's website there are apparently no such centers anywhere near me.

[A Reel Person]

There's a belt that drives the head up/down, and there's another belt that drives the tape forward in Play/Rec function. It's a pretty involved job for a DIY'er. The cassette mech has to be removed from the chassis. It's a disassembly job not for the feint of heart.

[kgf]

Thanks!

I had the lid off last night and saw the belt that lifts the heads. DO you think that perhaps the other belt needs an adjustment? I could see it not working at all because the belt broke, etc., but going too fast?! MAy be a gearing-type issue? I'm a pretty good DIY'er as long as it doesn't require an O scope or some fancy electronics knowledge. If it's just replacing a belt or maybe even a motor, I should be OK.

[A Reel Person]

Unfortunately, there is no adjustment for the belt. It's not like your car's fan belt! Heh. If you're a moderate DIY'er, you can do it. The symptom screams of broken belt, and a visual inspection verifies that. You need belts, my friend.

Good luck.

[kgf]

Quite correct! I've just removed the tape drive unit and underneath found what looked like small pieces of electrical tape. Upon closer exam I found the rest of the belt. It's the one that wraps around the large "chrome" wheel. I can only assume becauase of the symptoms that the large wheel acts a as a drag to maintain proper speed. Now I can't get through to Tascams website to find parts. Any suggetsions about obtaining belts?

[The Ghost of FM]

Originally Posted by kgf

Now I can't get through to Tascams website to find parts. Any suggetsions about obtaining belts?

http://www.tascam.com/ContactUs.html

Cheers!

[A Reel Person]

and I can find dimensions of those belts.

My best recollection is that the main capstan drive belt is 9.0" (flat) and the small belt is about 7.2" (square),... but DON'T use those figures until I've verified them. Also, a search of this bbs might produce a post with the correct belt sizes for the 234. I've done this job, and I've posted these numbers before. /DA

[A Reel Person]

(This was copied from a note I posted in June):...

The belts I was using to refurbish the 234 were:

- [capstan belt] Flat rubber belt, 9" total length, about 4mm wide and about .5mm thick, &
- [head/carriage belt] Square shaped belt, 7.2" total length.

Find a large variety of belts online, at www.electronix.com

... (the FF/RW mechanism is driven by two little rubber tires)...

The rubber tires I'm referring to are .599" OUTER diameter, qty 2.

======================================

There'ya go!

[kgf]

Thanks to both of you! I'm in touch with both Tascam and Electronix.com

[kgf]

Well i received the belts from Tascam and installed them. That was quite a job. It's all reassembled, but as soon as I turn it on the head carriage moves up and down without stopping. I admit that I spun that thing quite a bit and I figure it's a "timing" issue and I need to get it in the right spot. I have no idea how to figure that one out.

Also, I inserted a tape (clear case) then turned it on to see what would happen and the tape started moving immediately, but the reels weren't turning, only the spindle at the bottom (Guess that's the capstan). I should mention that while trying to figure out how to get the new capstan belt on I tried to loosen the white plastic screw that sticks out the back of the largeer heavy wheel that the capstan belt goes around. It turned one full rotation and one side of the slot broke off. That is, the slot that the screwdriver fits into. So, I left it alone and did not try to screw it back in. COuld that be causing this? Maybe that's some kind of tension adjustment?

Any more help you can give me on these two issues would be greatly appreciated.

[A Reel Person]

You might have gotten something mechanically misplaced, or maybe have plugged connectors into the wrong places. That's just a quick analysis.

I'll give a better answer, when I've had time to think a while about it.

[kgf]

Thank you so much for taking the time. I can't say how much of a help you've been. Even just having someone to bounce things off of.

I'm thinking that for the carriage problem I need to change the relationship between the motor and the assembly by rotating one without the other. I should have paid closer attention and marked them before I started anything.

[A Reel Person]

Like, maybe you got the gearing 180 degrees out of phase.

[A Reel Person]

Originally Posted by kgf

...but the reels weren't turning,...

This indicates one problem, (new), since you said the FF/RW function worked originally. The "little rubber tires" that do FF/RW are also the responsible for the takeup reel during normal play.

Originally Posted by kgf

... I tried to loosen the white plastic screw that sticks out the back of the largeer heavy wheel that the capstan belt goes around. It turned one full rotation and one side of the slot broke off,...

This would be the center spindle of the (capstan) flywheel assembly. Having loosened this one full rotation and then breaking off is not the end of the world, although it would be best to try to get it back down 1 turn. However, this is just the little "keeper" that is like the backstop of the flywheel. IF there is any problem whatsoever that develops from this particular "adjustment", it would be indicated by the capstan shaft being a bit loose, with play in the forward/back axis. That is, the capstan may float a slight bit, toward the very front or back of the unit. It's hard to describe, but I hope that's a clear image in your mind. All in all, the little white center spindle screw being loosened one turn is NOT indicative of your other problems.

As I said above, for the pinchwheel/headstack to go up & down constantly, WITH the added symptom that the FF/RW/Takeup mechanism is now defunct, would more than likely indicate a cross connection of connectors.

What I say is not gospel, and things should be taken very carefully, step by step, from here. However, I do have a 234 cassette mechanism that I have disassembled and sitting in a box, that's otherwise functional. (I was replacing the backlight bulb). SO, at a certain time, if your problems persist, I can pull this mechanism out and inspect it,... ALSO to include shooting a few digital pics of it, if necessary.

I'd verify the issues of both mechanical mis-assembly and cross-connections of cables. Anything is possible, and nothing should be ruled out, but to proceed carefully, step by step.

I will say, for the most part the connectors are color coded and pin-number specific to each area, so the risk of blatant cross connections is reduced,... but not strictly impossible.

Good luck, and keep us posted!!