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Author Topic: Otari MX 5050 will not play  (Read 2636 times)

Offline atentaten

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Otari MX 5050 will not play
« on: October 11, 2009, 01:50:22 AM »
I just received an Otari MX 5050.  When I press the play button, the heads engage and the reel starts to turn, but then it just stops abruptly.  It never gets rolling. Its as if once the tension is full, the play mode disengages. I know it will play if there is no tension.  Is the tape too tight?  If so, how does one go about decreasing the tension?  If not that, what else could it be?


Offline ironbut

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Re: Otari MX 5050 will not play
« Reply #1 on: October 11, 2009, 03:22:24 AM »
Hi atentaten (BTW we use our real names here).
Welcome to the forum.

First, if we can get an idea about your experience level with reel to reel tape machines we'll know how in depth we need to get (do you know all the operating parts for example). Also, if you don't have a manual, you can download one for free here;
You just need to navigate to the page with the manuals and jump through the hoops the site requires.

Look through the manual and make sure that the machines threaded correctly, then clean all the surfaces that the tape contacts from reel to reel to be sure there's nothing sticky stopping the tape.
Once those preliminary items are taken care of, tell us;

General questions first;

Did the former owner say that it was working properly?
Did he/she give you any idea how long the machines been sitting unused?

Thing to try to help diagnose the problem;

Will the machine rewind and fast forward properly?
If not, does it make any noise like the motor is trying to move the reels?
Does it stay in play or does it click off right away?
If you move the reel by hand while in play, can you help it to get going?
Before you hit play, is the capstan rotating?
When the reels stop turning, is the capstan still turning? If so, is the pinch roller moving too?
There is a switch on the tape tensioner that moves up and down, if you hold that tensioner down (or up depending on the machine) and hit play, do the reels turn in opposite directions (without a tape threaded)?

Well, those things should give us a few clues as to what's going on.
Report back with your results.
« Last Edit: October 11, 2009, 12:11:45 PM by ironbut »
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Offline Tim

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Re: Otari MX 5050 will not play
« Reply #2 on: October 11, 2009, 11:24:17 PM »
Doesn't sound like your capstan shaft/motor is spinning.  Check for correct power supply voltages going to the capstan motor drive circuit board.  If good, check board for defect drive transistors, defect caps, cracked solder joints, defect connectors.   If good, motor could be defect.

Tim Leinbaugh
Service Technician
with RTR specialty.

Offline atentaten

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Re: Otari MX 5050 will not play
« Reply #3 on: October 23, 2009, 10:58:51 AM »
Yes, the issue was with the capstan motor.  I had to turn it by hand to get it started.  I've since gotten the capstan replaced, and it works like a charm.