Fostex 80 several tracks muffled

[frilyd]

Hi there!

This is my first post on the forums, but I have been lurking around here for years. Now the time has come to join: I need help, and I don't know where else to turn.

I recently got a Fostex 80. I used the same machine around 2000-2001, and it worked perfectly back then. I am almost certain it hasn't been used much since. Before I even started using it after I got it, I cleaned the tape path (isopropyl alcohol) and demagnetised all metal parts in the tape path (very slowly and carefully). I bought new RMG LPR35 tape, and I've spent some time testing the machine. In short, it doesn't work nearly the way it did back in 2001.

After treading it correctly, I recorded a few minutes of vocals on all tracks. Only track 4 and 5 work really well - the rest is muffled, unclear, or/and has sudden drops in recording volume and high frequency response. The strange thing is that track 2 and 7 are worse than track 1 and 8. In effect, I now have a 2-track machine :-/

I'm not able to diagnose this. If the machine had come out of alignment, I would expect the HF response to get worse the nearer the edge tracks I got. Track 1 and 8 are definetely muffled, but not as bad as track 2 and 7. As it is now, I'm a bit confused, and would be grateful for any help.

If needed, I can post pictures of the heads (they have some wear, but should have plenty of life left) and sound clips of the affected tracks. If you want to hear me singing out-of-tune this close to Christmas, that is. Anyway, I could take this possibility and wish you all a warm, analogue Christmas and a correctly biased new year!

 

[mixsit]

Sorry I have no help to offer (not one of the real 'reel guys here) but I'm very interested in what this turns out to be.

(..from the early fostex club' here- -first multi tracks all fostex- (80', then RD8 chasing SMPTE on track eight..
Rally'n for a come back..

 

[sweetbeats]

Welcome! Glad to have another Fostex user here...don't own any Fostex gear myself, but Fostex users are typically under-represented so I'm glad to see one added to the ranks to the fine resource that is this forum.

When did you get the tape and where did you get it from? Kudos to getting new tape, but it is possible to get new RMGI tape that sheds. It would be hard to find at this stage, but it is possible if it was sitting for a bit. Assuming you got it from a dealer, contact them first to see about the tape. Ultimately it may mean a call direct to the RMGI rep but they really came through for me when I had purchased a roll of tape from an isolated early batch that shed...I can find the contact info if needed...anyway, I couldn't go more than a few minutes without experiencing significant response loss or even total loss of signal because of a piece of oxide. Anyway, if that turns out to be the problem, I am confident RMGI will take care of you.

Are you getting good signal when monitoring the input and your problem is definitely when you are monitoring or reproducing off of tape?

Make a few more posts so you can put up pics and links to audio files (or PM me with links if the pics and files are hosted somewhere...I'll put them up in a post for you). It would help.

Can you confirm that the tape is mechanically aligned (traveling down the centerline of the heads, no drifting or edge curling)?

Bias is the other thing I'm thinking about...the deck likely needs a full alignment to get a sense about what is going on.

Do you have the full manual? How about a test tape?

We'll try to get you going.

 

[frilyd]

Thanks for replying, Sweetbeats!

I got the tape about a month ago, from a reseller here in Norway. I waited for the tape a while, because they said they had to backorder it - so I suppose it is rather new. I bought 4 reels, so I should hopefully be able to eliminate tape as the error source.

Based on your advice, what I'll do next, is to clean the tape path (again!) and simply try recording on one of the other reels. I am slowly beginning to understand that even a tiny piece of oxide can cause dropouts or signal loss...

Monitoring works fine. Arming a track for record or pressing the "input monitor" button works, the signal comes through without problems. I'll double check by listening to the input over a period of time - I only did it for a few seconds on each track before recording.

I do have both the user and service manual, and I have a multimeter, a soldering iron, numerous screwdrivers and a demagnetiser. I can also cough up a scope, but I don't have test tape.

I'll post some pics later. Thanks!

 

[sweetbeats]

I am slowly beginning to understand that even a tiny piece of oxide can cause dropouts or signal loss...

Yes. In the picture below the piece of oxide was causing only minimal trouble, but I had a similar piece that was right on the crest of the stack and right on one of the tracks that caused 100% signal loss on that track. That picture is of a head on my Tascam 58 BTW, and that oxide was the result of that shedding RMGI SM911. If you are seeing any similar shedding or flaking I'd get in touch with your local RMGI rep and give them the batch numbers off of the tape boxes just to be sure.

Put up pics of the tape path when you can. That will be telling, and look to make sure the tape is running smooth and steady in the tape path.

You also may simply be dealing with oxidised pots/switches/contacts and cleaning them might resolve some of the issue. Tape path and tape first.

Also, to really know what is happening and what condition the deck is in you'll need a test tape.

 

[frilyd]

OK. I've been absent for a while because I've been busy opening, lubricating and cleaning the machine - I've got a few shots of the innards for you. As a warm-up for pictures of the tape path, let me present this picture of a surprisingly clean interior:


I didn't even have to dust this part of the recorder, but I took the opportunity to lubricate the reel holder bearings.


Just for the curious: The system control board

I also removed the cover behind the reel turntables, revealing a more grimy sight. Overview picture:



The next post will show the tape path.

 

[frilyd]

OK. Now for the ugly stuff. This is the record/repro head before cleaning. As Sweetbeats suspected, the brand new RMG LPR35 tape did shed. I hadn't suspected this, but it seems one has to be careful with new tape as well as old:


This doesn't look good.

The same head after cleaning can be seen here:

A bit better. If you examine this closely, you might or might not notice uneven wear pattern (slightly trapezoid) - I think it's difficult to see by eyesight, it might be perfectly OK. Opinions on the condition of this head are much appreciated.

Below is the erase head before cleaning:




And finally the capstan roller, not sparkling clean even after vigorous cleaning - I must have used 20 Q-tips on this one alone! The oxide seems to have stuck permanently. I can't get it off unless i use fine sanding paper or something like that, but then I probably shouldn't do that. Advice on this is also welcome:

 

[frilyd]

... and finally, just to give you a bit of reward for wading through this post: This is a picture of where I live, and about as it looks just now. The boy in front is one of my two sons, seen out skiing last year. I live in the house on the right, about 280 people live in Fjærland.


Fjærland, Norway, last New year's eve.

Back to the Fostex 80: The only question that remains before I put the covers back on the machine, is if there is anything else I should do. I will post back with results of recording to another reel once I've assembled everything again.

Thanks for your help! I don't think I'd get very far without it. It is much appreciated. Now, have yourselves a purr-fect Christhmas!

 

[sweetbeats]

Beautiful pic of home!

The tape shed may be a problem with your tape path and not the tape. You'll need to contact RMGI with the batch numbers. Keep in mind that the RMGI tape problem was relatively isolated and they got it under control pretty quick. It was related to the factory move to the Netherlands. They didn't anticipate that the environmental differences in climate between the old and new locations would effect the tape formulations and curing process, and there were some batches of tape that went out that didn't cure right and were prone to shedding. I got one of those rolls but the replacement roll that was sent out works beautifully. RMGI tape is good stuff and we need to be careful about forming blanket opinions based on isolated issues...should they have anticipated the issues? That's arguable, but they fixed it and are making good on any bad rolls that happened to make it to the marketplace, but you have to contact the rep and give them the batch numbers.

Bottom line though is that, based on the pics of your tape path, I'm not sure that the tape is the problem. That tape path looks like it might cause any tape to shed and there is some severe misalignment based on the pics of the record/reproduce head. I'm sorry to bear such news, but that is not a slight trapezoidal wear pattern, that is pretty extreme, and it is not an even trapezoid at that...It looks to me like somebody has already done a lap job on that head and it doesn't look like it was done evenly. So, serious uneven wear pattern potentially on top of an uneven relap...the zenith is seriously out of adjustment and has been for a long time. I can't tell from the pictures if there is gapping starting in or not on the top tracks, but I don't think you'll be able to pull that deck into spec on an alignment, and I think until that head is changed out (not sure if it can be relapped...I don't think it can) IMO you need to assume that it is the cause of your response issues.

The innards of the 80 do look really clean though...

While you've got the covers off I'd reseat the amp cards and put some contact cleaner on the connections.

For cleaning the tape path try cotton makeup remover pads instead of the swabs...good quality ones that are quilted and 100% cotton. Might help get more of the oxide off, and try denatured alcohol instead of whatever you are using...might help that capstan shaft.

So if it were me I'd be looking for a replacement head and/or pulling the existing headblock and sending it out to be checked to see if it can be relapped, then I'd turn the guides, and see if the lifters can be turned, get a test tape, put the fresh head/headblock back on and align the thing.

 

[frilyd]

Beautiful pic of home!

Thanks It is a beautiful place.

RMGI tape is good stuff and we need to be careful about forming blanket opinions based on isolated issues...

I agree. I will definetely keep on buying RMGI tape, and I was referring to new tape in general, not just new RMGI tape. Suffice to say that "Long live analog" is their slogan, and I heartily agree.

That tape path looks like it might cause any tape to shed and there is some severe misalignment based on the pics of the record/reproduce head.

It's actually more obvious in the pictures than in real life. Remember that the picture is taken looking down on the head, we are not seeing the head level-on. I'll post another picture taken in level with the head surface. But of course, you are probably absolutely correct. And it is bad news, especially to a first-time reel-to-reel owner - but heck, I haven't even paid for the machine yet. With a bit of luck, I might be able to give it back to the local radio station I picked it up from. And they have three Otari MX-5050's that might be worth investigating instead

try denatured alcohol instead of whatever you are using...might help that capstan shaft.

I've used both isopropyl alcohol and normal denatured alcohol. What would be recommended for cleaning the rubber roller? Alcohol diluted in water?

So if it were me I'd be looking for a replacement head and/or pulling the existing headblock and sending it out to be checked to see if it can be relapped, then I'd turn the guides, and see if the lifters can be turned, get a test tape, put the fresh head/headblock back on and align the thing.

Or I can just silently return the machine, and look for a new one elsewhere. This is an exciting world!

Again my kudos to Sweetbeats in particular and this forum in general. Maybe someday I'll be able to contribute too.

 

[sweetbeats]

Most of what I posted up last I've learned on this forum, and I'm glad to be able to give back too. It is a great community.

How much do they want for the 80?

You can use just water on the pinch roller, or window cleaner is pretty commonly used too. I've even heard of a mild sopa and water solution being used. Solvents will dry out the rubber. If the rubber is already dried out (hard/cracked) there are rubber restore products, but I consider those to be temporary solutions. If your pinch roller is in that condition it really is time to replace it IMO.

What percent purity is the iso alcohol you are using? 99% is best but hard to find, 91% is more common and works pretty good but the kind without any water content is preferred ("anhydrous" or lacking "water" in the ingredients). I don't think anybody recommends the 70% variety. Denatured alcohol is a preferred tape path cleaner by some over the iso alcohol.

Do put up some straight-on shots of the heads...and the Otari decks...8-track decks? Comparably priced to the Fostex? An MX-5050 8-track deck is leagues beyond the 80...both well-built and I've really heard some fantastic material tracked on an 80, but the 5050 8-track decks are 1/2" (keep that in mind as the tape is quite a bit pricier) 3-head decks built for the professional environment. Good decks and parts may actually be more readily available for those. See if you can go look at them and snap shots of the heads and tape path...interesting...

 

[sweetbeats]

What demagnetizer are you using? What model or brand is it?

 

[frilyd]

The MX-5050's are actually mastering machines, 2-track 1/4 inch. MX5050BII or BIII, I can't recall. Probably used for recording programs to be sent later. They are located around 120 miles from where I live, so I won't be able to have a look at them for a while... But they are indeed interesting.

My demagnetiser is borrowed, it's an old VMP Emag L. I don't know anything about its properties, but it buzzes and has easily detectable magnetic force when it gets near the heads or other metal parts.

This is the best head picture I was able to get - bad light, long shutter time etc.


So what do you say? Ditch it? I am quite sure I can get rid of this recorder without too many tears, so I am open to suggestions. Due to tape price and floor space, I'd be happiest with a 1/4" machine.

 

[sweetbeats]

Okay...maybe that head can be relapped, but it is pretty ugly lookin' huh?

How much are they asking for the 80?

Your demag unit sounds fine.

How well does the rest of the deck function? Is everything crisp?

You really won't know what you have until you can have the heads looked at. If they can't be relapped I'd pass as the Fostex 1/4" 8-track heads are hard to come by. Bottom line is that to get it to spec it'll be some kind of project.

The Otari decks are great...lots of the 5050 2-tracks around...the III model is the best, but if you decide to go with one of the Otari 2-track decks (or any deck for that matter) the idea is to worry less about which model you get and focus more on the condition of the deck.