Otari MX 50 problem

[NickH]

Hi Guys

I just got a otari mx 50. But there's a problem. For some reason the capstan motor is spinning in the wrong direction. Can someone give me some insight into why this is happening.

Also can some one point me to the direction of a owners and services manual for this unit.


Tanks,
Nick

[gamve]

Hi Guys

I just got a otari mx 50. But there's a problem. For some reason the capstan motor is spinning in the wrong direction. Can someone give me some insight into why this is happening.

Also can some one point me to the direction of a owners and services manual for this unit.


Tanks,
Nick

Hi Nick,
I have one that is doing the same thing. I've asked on a few forums and the likely culprit is the power supply. Manuals are hard to find for this machine.
Cheers
G

[NickH]

So are you saying something like a recap? Do you know if Otari still has the manuals for this unit?



Thanks,
Nick

[gamve]

Sorry Nick I don't know what is available from Otari. I have not progressed the repair on mine as I have a few others I am working on first. I had a look inside mine and there was evidence of leaking caps on the main supply board. Some of the fuses were blown and when replaced simply blew again instantly.
I will fix mine as it looks like a well built machine. The heads have no wear evident and everything else looks good. Will keep an eye out for a manual and will let you know if I do any good
Cheers
G

[NickH]

Oh I definitely going to fix it. It is a good looking machine. I actually have one more. The friend who gave me the mx50 also gave me a revox pr99.


Both I am very Jazzed about. I haven't tested the revox yet, I need a power cord LOL.

[NickH]

Well I scored a manual off ebay, albeit a little pricey. Now all I need is the schematics.

Did otari release these?



Nick

[NickH]

Well I found 2 blown fuses on the board changed them out and they blew again. I'm guessing it's the caps. Does any one know which fuses goes to what circuit?


Thanks Nick

[QuadMusic]

Well I scored a manual off ebay, albeit a little pricey. Now all I need is the schematics. Did otari release these?

Did you buy a CD by any chance and then find it was only the text pages of the manual? That's what happened to me.

I have the original printed manual for the MX-50N. In addition to the text pages you already have this manual has 2 pages of PCB layouts, 7 pages of exploded parts, and 7 page of schematics, all A3. I can only scan A4 at the moment. Maybe I could lend you the pages by post?

PC

[NickH]

It an actual paper manual and not a copy at that. But in retrospect I wish I wouldn't have bought it as I only need the schematics.

The unit is a mx 50 N 2. I don't know if there's much different between n2 and the just mx50.


Well I guess I will find out when I get is LOL.


Nick

[NickH]

Oh Ya I'm so happy. I figured out the problem with the mx50. The unit had been dropped. Not by me though. Well anyways the bottom bend in and was contacting the bottom circuit board shorting it out. I straighten everything out and what do you know the new fuses I put in didn't blow. And it worked.

Now there's still a little work to be done but it's all easy stuff. I need to do some more straightening as the bottom board is bowed. I will have to completely remove it to fix it though. So that repair will have to wait a few more days.


WAHHHHHOOOOOOO

Nick

[gamve]

Interesting....Will need to check mine, might be the same problem. Mine came delivered with one of the corner plastic trim fittings broken which more than likely means it was also dropped.

[NickH]

Yep that's exactly how mine looks. There's a metal brace bar under it and it's actually pretty soft. Thats what was hitting the board. I fixed it and never thought it was it. I'm not that lucky.


But I guess I have some luck still LOL. I was listening to a tape through the monitor and It sounded good for a little crappy speaker.

Now I just have to hope Otari still makes the tape tensioning arms as one of mine is bent and needs replacing.

Wish me luck,

Nick

[gamve]

Jeez I hope your right about this Nick. Was not looking forward to replacing all the caps on the power supply board. Will have a look when I get home tonight. Once you fixed this the fuses remained intact and the capstan started spinning in the right direction?
Cheers
G

[gamve]

Nick, You are a legend, I owe you a beer or seven.
Well, turn me upside down, wipe me bum and paint me blue. Be stuffed if my problem was nearly identical to yours. The strengthining bar in the case was not shorting but the 15.0mm long screws some dickhead had put in certainly were. I thought I was still in trouble as the screws have cracked and deformed the board in both back corners. With the bottom off the fuses are staying intact so I loaded a tape and kicked it in the guts. Guess What, The capstan now turns in the correct direction so the deck now plays....Yay. It appears to have audio as both meters are working but I need to do some mods to fix up the base. Does your manual tell you which pin is hot on the XLR connectors? I have some XLR to RCA converters but I need to know if they are wired correctly before hooking up to test the audio. I have some nice XLI Maxell Tape with some good classical on it at 1/2 track at 15ips can't wait to hear these on this machine. Heard the same tapes on an old Studer and it sounded very good on that.
Cheers
G

[NickH]

Weird huh.


Kinda spooky LOL


But oh so cheap to fix LOL

I haven't got the manual yet, probably next week. But I though that was a standardized connector so there shouldn't be any difference.

I just need a few parts for mine and it will be good to go. But even as it is now it still play. But I was just using the cheesy monitor on it. I didn't have it hooked to anything yet.

[QuadMusic]

Does your manual tell you which pin is hot on the XLR connectors? I have some XLR to RCA converters but I need to know if they are wired correctly before hooking up to test the audio.

The MX-50 (and MX-55) are 'hot on pin 3' on the XLRs. It's certain that your XLR-to-RCA converters will be wired with pin 2 as hot so you'll need to resolder inside the converters (or inside the deck).

Peter

[NickH]

So why did Otari wire there differently?

I'm just curious as I though it was kind of a industry standard.


But then again I'm kind of new to this stuff so shows what I know LOL.



Nick

[QuadMusic]

New to me - I only got my Otaris about a month ago. (I took a chance and bought 5 untested machines from an AV company - 3 x MX-55N and 2 x MX-50N. I want to keep a nice MX-55 and sell the other four for what I paid for all five.)

This is as much as I know:

"Some audio equipment manufacturers reverse the use of pin 2 (properly the normal input) and pin 3 (inverting input). This reflects their own previous usage before any standard existed. Pin 1 is always ground, and many connectors connect it internally to the connector shell or case."

From http://en.wikipedia.org/wiki/XLR_connector

[NickH]

Well you learn something new every day.

[gamve]

The MX-50 (and MX-55) are 'hot on pin 3' on the XLRs. It's certain that your XLR-to-RCA converters will be wired with pin 2 as hot so you'll need to resolder inside the converters (or inside the deck).

Peter

Thanks Peter, that will get me going.
Cheers
G

[gamve]

Converted my XLR to RCA adapters to pin 3 hot (Thanks QM) and hooked it all up last night. I have a 7" Maxell XLI with the Boston Symphony Orchestra doing some good classical from the early sixties taped from FM at 15 ips. Sound is very very good.
Out of my 5 R2R machines now only have one left to get going.

[QuadMusic]

Good news. After a few weeks use I like the Otaris a lot - especially the MX-55N which I highly recommend if you can get one.

I want an MX-5050 now but most are for sale in the US, unfortunately.

Peter

[NickH]

I wanted a mx55, the console type. But I won't look a gift horse in the mouth.


I haven't even had the chance to really hear my Otari yet. But there are tons of mods you can do to it.



Nick

[NickH]

Interesting fact,


My friend told me the outputs on the otari's will automatically switch form balanced to un balanced.


Nick

[QuadMusic]

My friend told me the outputs on the otari's will automatically switch form balanced to unbalanced.

In the sense that the Otari doesn't "know" that you're using XLR-RCA conveters I suppose that's automatic.

On the MX-55 the manual says "OTARI recommend that UNBAL/BAL switch on the Output PCA should be set to UNBAL position on the case of Unbalanced output operation."

'PCA' could be a typo. but it refers to the Audio Amp PCB behind the VU meters. The problem I have is that I can't find any switches!

Regards,

Peter

[NickH]

Well to this was a mx55 but I haven't got my manual yet, hope it will be here in a week or so. I still have a lot of work to to my mx50. And I'm going to be in there even more.


Oh by the way I got a quote for a new tape tension arm guide, and watch out, 245 bucks, just for 1 guide pin. I will make my own now. I'm going to take my lead for what the tape project say to do for the mx5050. I'm going to use all thread ceramic washers and 2 small bearings.

Because I'm not going to pay that much if I can do it better myself for less. But when I'm in there I will look for a switch. But you would think they would put it on the outside though, wouldn't you?


Nick