Tascam 388 RTZ & counter problems

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unarmedman

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Hello homerecording.com! I ran into these forums while searching for info to help me fix a problem I have with a Tascam 388 I just bought. Seems there's quite a few 388 users around here!

Here's the problems:

1) The return-to-zero function does not, in fact, return to zero. Not even close. It usually falls anywhere from 40-50 seconds after where I set "zero" to begin with. So, the counter will read 0:00 when it's probably more like 0:40.

2) The counter will sometimes but not always work when recording. In the last session I had it would not work for a majority of the recording time, although during playback, FF, and RW it does work.

While both of these problems aren't critical to using the 388, they are pretty big annoyance, and they mainly impact how much tape I am able to utilize on a reel (with guessing where I am, writing down counts instead of relying on the machine, etc.) Mainly I'm bothered because it just shouldn't be this way. A tech I spoke to in Tampa (about 2 hours away from me) said it sounded like a belt issue, but they charged $40/hour and $30/belt, and he said he wouldn't just replace 1 belt. So in the interest of saving money, I'm hoping to do this on my own.

Does anyone know what this problem could be? What should I be looking for? Am I getting in over my head w/this repair?

Thanks in advance for your help!
-Eric

p.s. And, FWIW, the tape path was cleaned very well before I started using this machine, so I don't think its a sticky shed issue. Thanks!
 
Not the belt. There's only one belt in the 388, and that wouldn't cause this problem.

The roller immediatly to the right of the pinchwheel is the tach roller. The tach roller is the source of counting/position sensing on the 388. I haven't looked directly (although I looked in the manual), and I'd believe it to be an led photosensor and a tach wheel. Either there's some looseness in the tach roller/tach wheel assembly itself, or maybe the tach sensors need cleaning.

If it won't count accurately, look at the tach roller and sensor.

If the counter display goes on & off intermittently, look for a bad connection. Maybe reseat the connectors.

;)
 
First thing I would do is unscrew the black cap on the tach roller that reel mentioned and take if off of the machine. Be careful there is a little back washer on top of the roller under the cap.
Maybe use just a q tip to wipe the two little sensors off that you will find under the wheel off. There could be some dust or funk on those that would keep them from working correctly. Also could be the rubber on that wheel has got hard and needs some rubber conditioner used on it to soften it up some. Could be hard and letting the tape slip. Also could be the shaft needs some lube (light oil) on it.
 

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Nice!

So, looking directly at the sensor, do you think it's optical or maybe a Hall-Effect sensor? I think maybe a hall effect sensor,... that detects the movement of a little metal tab underneath the tach roller.

Herm's also right on with the note that if the rubber on the tach roller is hard, it will not grip the tape as it passes, and therefore would throw the counting off.

;)
 
Boy I dont know Dave Im not that familiar with those at all.
 
Hey guys, thanks for the responses!

I will look into both of these issues tomorrow when I'm at home & have time to check it out. The rubber on the tach roller was a bit hard, but being my first tape machine, I'm not sure if its too hard.

You're responses have also brought some new questions for me: First, can someone recommend a rubber conditioner? Second, when I clean the sensors with a cotton swab, should I use an alcohol-based cleaner or head cleaner on it, or just use the swab dry?

Thanks in advance for the help! If it is a hall-effect sensor, it seems more likely that the problem would be linked to the roller rather than the sensor. Just a thought there.

-Eric
 
Unarmedman,
Recently I had the exact same problem with my TSR-8, and this is what I did to solve it. I used a dry q tip, and very lightly swept across the two sensors, and then I cleaned them again with a puff of compressed air making sure not to shake the can and to hold it upright like the directions say. You may also need to clean off the backside of the counter roller as mine was all greasy and full of little dust hairs which probably kept the sensor from reading its black/silver pattern properly. Another thing I did was lightly oil all of the roller shafts with 3-in-1 being careful not to drip on anything that didn't require oil. Finally, I conditioned the counter roller and pinch roller with Caig Laboratories' "CaiKleen RBR" Rubber cleaner/conditioner which can be bought from their website at: www.caig.com. After I did everything I carefully put everything back where it belonged, making sure not to lose any of the little washers used on the rollers, and my problem was solved! The majority of this information was given to me by Beck and Ghost so thank them if it works and good luck!
 
Hey, just wanted to give an update on what I tried:

Cleaned the tape path, used fantastic on the pinch roller & tach roller, took off the tach roller and wiped the sensors with a cotton swab, cleaned the bottom of the tach wheel, and reattached everything.

So far, RTZ seems to finally be working! I only tested it twice, the first time 3:40 into the tape, the second time 24:00 in. Both times it went back to the exact same spot. Finally!

Now, one time when I pressed play (before I had reset zero) the tach roller didn't spin, and I noticed the counter wasn't moving. So that problem isn't eliminated yet, but I do know now that it is because the tach roller isn't catching the tape. So, I'll be ordering some of that Caikleen RBR, and will try that out!

Thank you all so much for the help on this - saved me a lot of stress (and money!).

One more question - I was reading someone's post about doing "tails out" winding....is that really necessary? I hadn't heard of that until today, and I hadn't been doing it either.

-Eric
 
I had a similar problem on one of my 388's with the tach counter not always starting or being hesitant. I did all the cleaning/ lubricating/shaft polishing/rubber conditioning/etc to no avail. I DID find that when I gently pulled the right hand tension arm down a bit, the counter worked fine. That said, there are servo arm adjustment pots up top that can be tweaked to position these arms. This solved the issue, the tension arms ride in what looks to be the correct plane, and it runs/counts perfect.
Anyone see any downside to doing this?? I presumed it was just and adjustment issue....
 
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