Nak mr-1 #4 slowdown issue?

jayk

Super Member
well! i do declare!
tonite had a tape playing away in mr-1#4 (with the new i-tire) and about 4 mins after starting side 2 on a maxell udxlII c90 it started a gradual slowdown until it stopped. at first i thought it was some special effect in the music as it's new wave-ish music on a tape i found at the thrift store.
but when i replayed the tape and tried a different tape with same results it's-
"houston, we have a problem".

deck is still open after installing i-tire so i looked to see if it was anything obvious.
new tire looks ok. ff/rw work fine.
very gradual slowdown just in play mode.

main belt looks like it might be slipping when this happens. deck has warmed up after playing the 1/2 hour or so, the warmth helping the probably worn belt to slip?

anybody got any thoughts?

thanks.
 
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it was turned off for a half hour, turned it on 5 mins ago, tape played fine.
but as it's late i didn't let it play for a while to see if it stops again.
i'm really thinking warmth and then a worn belt slipping.

tomorrow.
 
hmmm, #4's been playing for over an hour now and no slowdown or other issues.
? huh!

curious-the tape that was playing last night that #4 slowed down on is a maxell XLII c90 but a newer looking version than the ones i usually see/get/have.

funny thing is after last nights slowdown, i tried the same tape in mr-1 #1, which is in excellent shape, has never messed up at all and also has a new i-tire (6 mos ago and not used a lot since) and in the last 5 mins of said tape, it started eating the tape, didn't stop but kept going and eating the tape. luckily i got to it after about 1 min of tape eating, just lucky, i guess. couldn't hear it.

so, could that particular tape be the culprit re slowdown, somehow?
i'll try that tape on my sony or some other deck and see what happens.

#4 still going strong.
 
going on 2 hours now. no slowdown. WTF!

must'a been the nak gremlins at work last night causing the slowdown.
 
Man, I had the same problem last week cept my "Michi" Mr-2 was going up and down like a yo-yo. now it works fine. Good thing we all have a couple spares!

:)
 
Man, I had the same problem last week cept my "Michi" Mr-2 was going up and down like a yo-yo. now it works fine. Good thing we all have a couple spares!
:)

oh yeah? any idea what caused it? or 'fixed' it?

once, i accidentally spilled cleaner or some liquid on a belt in my sony deck. it caused the same thing, up and down speeds, but after it dried it was ok.
so i'm wondering if i had spilled anything into my nak. but i don't think i had any liquids near the deck last night.

i still haven't closed it up as issue may crop up again. all i can do is wait and see.

edit-by the time i turned it off this afternoon, it had played for 3 hours with no slowdown or other issues.
go figure...
 
man, i cleaned everthing and left it on over night, just on, not running. now it is rocksteady "knock on wood" or "nak on wood"
 
#4's been playing for 2nd 'session' this evening for the last 2 hours, nonstop. no more slowdown or other issues.

i'm wondering-it probably went unused for many years until i got it. maybe it just needed some usage to get it working consistantly.
i read about that happening with lots of other decks.

seems ok, now.
 
fired up #4 this am, major flutter right from the git-go. bummer.
yesterday, it ran perfectly for 3 hrs, then later for 2 hrs.

but i can see the main belt swaying a bit. when i nudged it with a thin straw, it shifted around on the flywheel
definitely a loose worn belt.
should be doable.
 
Jayk - you and I are just "blessed' with these MR-1. I was able to get an RCA to Xr (?) converter and tried my other connection and the deck works great. I had to step out of the room and found the deck in the play/pause locked mode. It seems the tape got stuck and now I can not open the door or get the deck out of this "stuck" mode.
Any suggestions?
 
Jayk - you and I are just "blessed' with these MR-1. I was able to get an RCA to Xr (?) converter and tried my other connection and the deck works great. I had to step out of the room and found the deck in the play/pause locked mode. It seems the tape got stuck and now I can not open the door or get the deck out of this "stuck" mode.
Any suggestions?
oooh, bummer. up and down, these things are.
at the moment i'm feeling a bit sick (copd) and have no suggestions.

i suppose you turned it off and then on. didn't help?
can you see if tape came out its shell or not?
 
I did turned it off and on. No help. Can not open the door so can not see whether there is any tape pulled out - can mnot see any through the door.
 
I think there is a way to manually rotate a cam or gear to release the heads from the tape. There is a thread on here somewhere with instructions. Try the Google search under AK search.
 
Nope. Tried last week but could not figure out how to open the door.

I just got home from a business trip and will likely await some better days to touch the MR-1 - when I am not dead tired. I am not giving up just yet. For the period it worked a few weeks back it sounded crazy good with the Dynaco A-25 speakers and Kenny integrated...
 
The function cam motor likley has a dead spot. It would be the one motor sitting sideways as opposed to the capstan and reel motor. Used to just replace them, but with Nak parts being tight I would then remove the motor and clean the comutator contacts, and lube the brass bearings. Then run it at a 12 volts in both directions for a few short bursts. Works fine every time.
 
Thanks I will try this weekend. I never done anything even remotely similar to this though. Any suggestions what to pay attention to or how to approach this? What tools do I need?
 
Well, using a #1 screw driver you will need to remove the black back plate from inside the cassette well, then you can access the one screw to the shaft of the function cam bearing, then remove the two screws holding the function cam bearing support bracket. then you should be able to pull out the whole assy. lightly pull back on the three cam follower switches to remove the cam. now you will have access the the two screws holding the cam motor to the bracket.
 
I might be misunderstanding what you are suggesting, but I would need to open the cassette door first and pull the tape out I think. My issue is that I can not open the door as seemingly the cassette is stuck.
 
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