a reel problem

  • Thread starter Thread starter FALKEN
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FALKEN

FALKEN

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so I bought a MX50 on ebay from a guy who refurbs them. and when I got it, the left tension arm was all wacky, and it was causing an inconsistent sound, because more or less pressure was being applied to the tape as the reel spun. So I called the guy and he immediately had fedex come and pick it up and he replaced the reel tables and 2 weeks later I now have it again. only the tape is still rubbing against the right wheel and the left tension arm is still a little wacky and the recordings it makes are in my opinion unusable. due to this wandering hissy sound that comes in and out. The auction advertised "100% working pro sound" yadda yadda. so I call the guy back and tell him "look" refund my money and fix it or sell it to somebody else I dont care. he asks me can he have fedex come pick it up, and he'll fix it again, and then I can drive down there (about 2 hours) and pick it up at his house. I told him I'd rather not, that ive already wasted enough time on this venture, just get rid of it and refund my money. he said fine, and he would have fedex come on monday.

then his wife calls me back, and insists that I come pick it up. I explain to her that by the time it is fixed and I can get down there to pick it up, the claim period on paypal will be over and I will be left with no recourse so I really am not comfortable with that. she assures me that they're not trying to screw me yadda yadda just not to worry about all of that. which I believe. but I explained to her that maybe my opinion of what a solid pro machine should sound like is not the same as theirs, so I might drive down 2 hours, and they play it for me, and I say "that is not 100% pro working machine, I want a refund". she says not to worry about that either. very nice people, but I mean, gosh, what would you do?? She also claimed that he is the only guy in the state that can repair these things so It would be good to have him on my side, if in fact he does know what he is doing, which is questionable. maybe he is so old he doesn't notice the volume wavering?? I mean, the right reel makes a click every time it revolves......I don't think I'm crazy. but I have to say that my fostex e-16 is a lot more solid than this old thing.....I am almost thinking about just scrapping it all and getting a 32. I bought a 42 before and that one was bogus too. for my life, I cannot seem to get a working mixdown reel!!! so, yet another project will be mixed to the PC, what a letdown.
 
Sounds like the problem may be a little beyond the seller's ability. At this point I would end the ordeal and get a refund. You could also get a partial refund and take it somewhere else to set up right. Not seeing the unit it is hard to know whether that would be worth it or not.

The MX50 is a nice machine as the model goes, but that particular one may have seen better days.

Follow your instincts and don't let your paypal/ebay options expire.

-Tim
 
so I swabbed a roller and it was like freakin orange.

I guess the guy ran some old tapes through it or something, because this thing had some buildup. I figured since he refurbed it and sold it in "like new" condition that this would have been done.

Now most of the noise is gone, but the tape still rubs on the reel as it is turning, which still causes some unnecessary movement on the tension arm. I am pretty sure if I were able to even out the reel tables so that they did not rub, i would be in good shape. I don't have the manual, but it is a rackmount version, so taking off the back panel looks like a pretty easy job. its just where to go from there...

does anybody know what the "SRL" button does? it almost blew my monitors.
 
FALKEN said:
so I swabbed a roller and it was like freakin orange.

...I figured since he refurbed it and sold it in "like new" condition that this would have been done.

does anybody know what the "SRL" button does? it almost blew my monitors.
Click to expand...

Yeah, I would think it might be cleaned, but he could just have an old calibration tape that is shedding really badly.

SRL stands for "Standard Reference Level" and pressing the button will switch the VU meters to read standard reference at 0 VU for calibration. It should only change the level and what you are seeing at the meter. (just realized you said blew your monitors, not motors -- yeah it could do that) :)

Tape rub is pretty common, but should always be corrected. If everything else is in order (reel tables and such) you may just have a reel that is not straight. Otherwise reel table height adjustment usually solves it. If it can't be corrected it could be a bent motor shaft or warped reel table.

Here's a pdf manual for ya! :)

http://www.otari.de/support/pdf/MX50II_E5.PDF
 
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FALKEN said:
so I swabbed a roller and it was like freakin orange.

I guess the guy ran some old tapes through it or something, because this thing had some buildup. I figured since he refurbed it and sold it in "like new" condition that this would have been done.

Now most of the noise is gone, but the tape still rubs on the reel as it is turning, which still causes some unnecessary movement on the tension arm. I am pretty sure if I were able to even out the reel tables so that they did not rub, i would be in good shape. I don't have the manual, but it is a rackmount version, so taking off the back panel looks like a pretty easy job. its just where to go from there...

does anybody know what the "SRL" button does? it almost blew my monitors.
Click to expand...

Go thru the steps that Beck posted the PDF for. Otari manuals are pretty good regarding step-by-step calibration (don't skip any steps), go from top to bottom.

Worse case scenario is you might need someone that services the machine to do an overhaul. Before I got my Electronics Degree I had a guy work on my Otari 2" 24 Track and it cost me over $800 to get it up to spec (even though it was in decent working condition). Like I said since then (almost 10 years now) I've serviced, replaced, re-cal'd, and etc since then without any problem.

A warning: don't swab the rubber rollers using alcohol based solvents. You do need to use rubber cleaner otherwise you'll dry out the rubber therefore it'll flake and lose grip. The heads and other metal guide rollers should be cleaned with head cleaner; wipe but don't rub 'till you don't see any more brown residue.

If you do the above and still "hear" dullness or excessive hiss during playback then it might be the heads themselves (if everything was calibrated / azimuth'd correctly first - with fresh tape and a reliable SPL tape). Was there any documentation about the head life? If you go thru all steps, like I said and you're still getting problems you might need to get the heads re-lapped or replaced. Any tape machine I've bought over the last 11 years I've always requested a documented head lap from JRF in New Jersey, they're the best.

-- Adam Lazlo
 
analogelectric,

the heads are like new.

the machine is working pretty good now. I looked at the link to that manual. Thanks Beck!!!! I am pretty sure that I can go in there and even out the reel tables. one question, if the reel table should be .25" from the deck plate......the deckplate is just the front of the machine, no?


I am wondering if anybody can help me out with this left tension arm and what it should be doing. on my larger E-16, the tension arms stay put, and only react to the transport controls. however, on this mx50, the arm seems to be moving around as the tape plays, and it is still causing a small amount of wavering hiss. the right arm stays put. cleaning the machine and having the tape not rub the side helped but has not eliminated this problem completely, as I hoped it would. now I am not so sure a reel table adjustment will fix this machine. can anybody please shed some light on this?

I don't really think I can use the machine for much...the slightest hint of this sound totally ruins it for me. I could deal with a constant hiss, but not something that sounds like the ocean. its a lot more obvious with a test tone or just recording silence than with a recorded song, though.
 
Yes the deckplate is the frontplate of the machine. The left tension arm should not be moving around that much, but tape rub can cause it.

You are sure you have the tape threaded right as in the manual and the reel size switches are for large reels. (or small reels if you are using 7").

You are using new tape, right?
 
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thanks for all of the help so far.

the tension arm seems to be moving too much even if the tape isn't rubbing.

the tape is threaded exactly as in the manual.

the switches are for small reels, I am using brand new 7" tape and a brand new takeup reel.


I actually tried to run the machine without threading it around the left arm, just to see if it would work any better. I was able to deduce that the left tension arm is not the cause of the problem, but a symptom. the tape is not running at a constant speed. I am not sure which side it is but I believe it is the left one. It might be dragging a little every revolution, which is probably putting pressure on the tape and heads. that side is also closer to the face of the machine than the other side.

what do you think?

I should have some time tonight to work on it.
 
Check the reel braking mechanism -- could need adjusting – may be rubbing if the brake band is bent out-of-round. Could be a bad brake solenoid. I’m not sure if the brake solenoid is normally closed or normally opened on this model. If the brake closes at rest (pretty common) a solenoid would have to release the brake during play, FWD, RWD. It could be weak, so not opening quite enough, or something could be obstructing the free movement of the arm that opens the brake band.

I'm about out of ideas that would lead to a simple fix, right now anyway. I'm afraid it could even be electronic failure, as this model has microprocessor-controlled tension.

I would be thinking about having a service tech check it out.

Does the machine make a lot of mechanical noise? Maybe the capstan and reel motors have never been lubricated since it was new.

-Tim
 
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I have an Otari MX 70 16 track that had the exact same noise problem on a few channels. Otari said to replace the record relays. Did that on all 16 channels and the noise went away. Got the relays from Mouser Electronics for about $1.50 each.

Jerry
 
I think Jerry may have something with the relay thing. Just today by pure chance I was reading through an old recording magazine from 1991. Here is what it said in the Workshop Section about the MX5050, which is very close in design to the MX50:

“There are two relays marked RL301 and RL401 that are usually marked Omcron, but I don’t recommend them. They aren’t sealed and the contacts wear quickly…. If your MX5050 exhibits drifting and wavering tones, or is a little noisy, the relays are probably at fault.”

I checked the pdf manual for the MX50, which I posted previously. It shows the rec/repro relays in the same place -- RL301 and RL401 on the Audio Amplifier Circuit Board, Otari part number RY2CC105. Unfortunately the exploded view pics aren’t included in the pdf manual, just the part numbers. They shouldn’t be hard to locate though by poking around.

I hope this is good news! :)

-Tim
 
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I also have an Otari MX50-N and plan to replace all the relays. When i got mine, the seller said it "was like new". Long story short, it was far from it. I called Otari about spare parts ( aske for Daina, cool guy) and they have tons of 'em. I replaced the pinch roller and reel locks on mine, gave it a "lube job" and demaged the heads. Works great now. I understand these machines went for $3000 new!

Jerry
 
well unfortunately it went back to the seller this morning. I tried to even out the reel tables, which were not even. this would have been the first step. I couldn't get the screws loose, one of them was stripped, and I wasn't about to take the entire machine apart. The seller is supposed to be a pro. He just can't pack these things for crap. but yeah I think a lube and replacing the relays along with a table height adjustment might have gotten it off the ground. unfortunately the seller is not reading me when I say "refund" because all they hear is "repair". "no repair! refund!" so I will probably have to file a claim. I think twice around is enough. they want to repair it again and have me drive 2 hours to pick it up in person, where I fully expect to find it not in "mastering" condition as the auction stated. I really would like to learn to repair these things on my own; but in this case I wanted one working and I paid for it working...if I wanted to do repairs I would have paid much less. the seller is not reading me though....
 
That’s too bad – sorry to hear it.

It’s tough because you said they seemed like nice people. However, if they decide to be difficult, when push comes to shove I follow the WWWWD (What Would William Wallace Do?) rule. :eek:

If they are not hearing you make sure they know that you know your options.

-eBay Complaint process
-Federal Internet Fraud Complaint Center: http://www.ifccfbi.gov/index.asp
-Your State Attorney General’s Internet fraud division

In my state misrepresenting an item falls under Internet theft and fraud statutes. It’s not a civil matter – it’s criminal.

Only you can be the judge of what type of people these are and whether taking a hard line is appropriate. Some people can’t be reasoned with. The bottom line is they took your money and did not give what you paid for.

-Tim
 
Thanks, Tim.

I don't think its a matter of intentional fraud, I think they spent the money already. I think If I file a claim their paypal account will freeze and stay that way for a long, long time, so they are trying to talk me into a repair. arrgh. maybe i am better off mixing down to my pc anyway.
 
FALKEN said:
maybe i am better off mixing down to my pc anyway.
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Ahhhh! I shudder to think… Get hold of yourself man! :D

After this bad experience is all over look for a Tascam 32 or 22-2. I have two of the 22-2 and I love them. They have no bells and whistles, but are reliable, easy and inexpensive to maintain and sound just as good as higher priced full-featured models. The sonic performance of these little machines equals some larger Tascam and Otari models.

It’s a straightforward, K.I.S.S. design – not as much to go wrong.

I would have no qualms about mastering a commercial release on the 22-2 anymore than I would an Otari MX50, or 5050.

Most of these older machines can be improved with a few simple mods, like newer op-amps and metal film resistors in the audio path, but that’s half the fun of it for me. :)

-Tim
 
Beck said:
Most of these older machines can be improved with a few simple mods, like newer op-amps and metal film resistors in the audio path, but that’s half the fun of it for me. :)
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My 32 should arrive soon (I'm getting RBG to combine freight with a telemetry unit for our Mid Dome site which is probably a couple of weeks away) - what mods would you recommend?
 
Beck said:
Most of these older machines can be improved with a few simple mods, like newer op-amps and metal film resistors in the audio path, but that’s half the fun of it for me. :)
Click to expand...

and my inability to do this sort of work gets me again. I wish I could learn that stuff.
 
arjoll said:
My 32 should arrive soon (I'm getting RBG to combine freight with a telemetry unit for our Mid Dome site which is probably a couple of weeks away) - what mods would you recommend?
Click to expand...

Andrew,

I don’t know the internals of the 32 like I do the 22-2. I can tell you exactly which resistors to replace on the 22-2, but not the 32. As far as the op-amp, the 32 was made for over 15 years with some revisions in circuitry. If your unit has 4558 op-amps on the rec/repro PCB you’ll want to replace those with 5532AN op-amps. This mod alone will give you better noise and distortion specs.

The units I know have the 4558 are the 80-8, 32-2B, early 32, and 22-2.

I’m sorry I can’t help with resistors. If you get a manual with PCB view and list you will probably be able to figure it out. The general idea is to replace the cheap carbon resistors in the signal path with high quality 1% or 2% tolerance metal film resistors. The cheaper carbon types contribute thermal noise. It adds up in a circuit with a lot of resitors.

Hope that helps,

-Tim :)
 
Beck said:
Andrew,
If your unit has 4558 op-amps on the rec/repro PCB you’ll want to replace those with 5532AN op-amps. This mod alone will give you better noise and distortion specs.
Click to expand...

That's a good trick. I may try that myself. What about the 4459 opamp?
And how about the relays? Know any good replacements for those?
 
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