MX-5050s are Hard Workers

MX-5050s are Hard Workers

by Randy Schell, Pres/Owner
Schelectronics Tech. Serv.

Houston TX . . . I remember, a number of years ago, rummaging through the cartons of equipment that had come in for a new class A FM that I had been asked to construct.

"Wait a minute. What is this? He bought a Space Invaders game? Damn, he bought a couple of them! No, that's not Atari. That's Otari. I think I've heard of them."

That's pretty much the way it went . . . fear and trembling over the thought that some equipment supplier had a couple of these oddball reel-to-reel machines sitting on the shelf from a company no one had ever heard of, and wrote them into a package for a new radio station to get them out of his warehouse. I had a feeling I was in for a lot of trouble, and that the MX-5050s were in for a lot of downtime.

As it turned out, though, the darned things worked pretty well. Their specs seemed to be okay, they held up to operator abuse with some degree of tenacity, and they had most of the features necessary for an operation the size of his. They didn't even look too bad.

Maintenance was a little scary, though. At first I thought Otari didn't realize that station owners actually made their engineers repair stuff. That would explain the fact that the manual had no schematics.

But when I called them for some help and the technician answered in Japanese, I decided it didn't matter about the schematics. I can't read Japanese. Luckily, there were no failures in the first couple of years that required reading print to repair.

By that time, the station had expanded and bought two more MX-5050s. These came with documentation and, though an "improved" version, they were close enough to the original 5050s for the schematics to be helpful.

Well, Otari must have been selling quite a few of these things by then. Because now they had developed the MX-5050BII, which is the actual subject of this article.

I don't think, by this time, that anyone reading this is totally unfamiliar with Otari's most modest reel-to-reel machine. It has become something of a standard with the "production-on-a-budget" crowd, and rightfully so.

The 5050BII has almost any feature the average production room might need. The most obvious improvement over the earlier models is an LED display real time tape clock. The predecessors had mechanical tape counters with no actual correlation to time.

Also new to this model is a dual frequency (1 kHz and 10 kHz) test oscillator, with "push on/push off" activation for each frequency. With the machine in the "source" mode, the oscillator appears at the outputs, making it usable as a handy, albeit simple, test device for the whole room. The second generation machine had an oscillator, but it was single frequency (1 kHz) with momentary activation.

As with the other two versions, the MX-5050BII has an extra ¼ track playback head (for editing down the phone bits you've been recording on that old machine you dug out of the attic), individual sel sync for the left and right channels, separate mic and line inputs and level controls, switchable standard reference level on the reproduce amplifier and

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MX-5050BII

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an edit dump.

Maintenance is simplified with a swing out record/play amplifier, accessible when the machine is on its back. Equally as crucial to ease of maintenance is improved documentation, including real schematics, circuit board layouts and exploded mechanical diagrams. Record bias, level and equalization are adjustable from the front panel.

Mechanical editing is probably the MX-5050BII's weak point, but it's a minor one. The heads are a little hard to get to, particularly if you have short, fat fingers, and the splicing block occasionally lets go of the tape. Nothing a longer grease pencil and $17 won't cure.

The other thing I'd like to see on this machine is a SMPTE center track. But that would take it out of the $2,300 price range, and that's one of the unit's best features. The cost versus features and quality make the MX-5050BII one of the best bargains on the equipment market.

And if you know a licensee, studio owner, or advertising agency that isn't looking for a great bargain, tell them to give me a call. I'll build them a studio they won't believe.

Editor's note: For more information, contact John Carey at Otari: 415-592-8311. The author may be contacted at 713-558-5121.