JVC RC M80 Play function issues!

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BoomboxLover48

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Dec 3, 2010
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Belts all replaced but ran into a problem!

REW and FF works fine but sometimes FF won't engage but in PLAY mode the take up axle don't engage at all. :sadno: Spend all day on fixing the deck but play will not engage the take up reel :bang:



After a whole weekend spending on cleaning, lubrication and belt change finally got stuck with PLAY mode where the head assembly goes up but won't engage the take up axle. But on FF it works intermittently. The deck was a bit complicated to remove and work on.

Since the take up axle won't turn in play mode auto shut off kicks in immediately.

Any help on solving this issue is greatly appreciated.
 

baddboybill

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Jul 14, 2009
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Royce I wish I could help. So the heads go up but not all the way to engage play fully :hmmm: If that's issue then I can say that when working on Joes Conion c100 I had same issue but it only happened when deck was in front case. When I tested deck outside of front case worked fine every time. I looked for obstructions but to no prevail I couldn't find any. Still has me stumped to this day. If you can test deck while not in front case try that and see what it does ;-)
 

BoomboxLover48

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baddboybill said:
Royce I wish I could help. So the heads go up but not all the way to engage play fully :hmmm: If that's issue then I can say that when working on Joes Conion c100 I had same issue but it only happened when deck was in front case. When I tested deck outside of front case worked fine every time. I looked for obstructions but to no prevail I couldn't find any. Still has me stumped to this day. If you can test deck while not in front case try that and see what it does ;-)
Hi Bill, That is not the case here. It goes up all the way and the pinch roller engages fine and it all locks in place but the take up axle wont turn. Since it is connected to the auto stop sensing magnetic wheel via belt, it will activate and shut off the play. I need to get a good view of the mechanism that drives the take up reel axle. It could be a contact wheel or something like that that is not engaging to turn the take up reel drive axle. FF works 70% of the time but hesitates to function at times. FF could be driven by another contact wheel. The deck has got two motors. I need the manual to see how this is all lined up. I helped the take up axle to turn to see if it got any flat spots but that didn't help. I also assisted the play mode head assembly to go a little more higher to see if that helped. Nope it didn't.
 

BoomboxLover48

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I assume there is a contact wheel inside that is all worn out or a lever assembly not engaging with the wheel. I am a little shaky to open the whole thing to see what is inside it without a manual.
 

Alberto

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Jan 3, 2013
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A Royce, can you see if the motor runs when you engage the play button? Does M80 have the same cassette transport as a M70? If so there is a mechanical plate/bar that is part of the auto stop on the front side just behind the head assembly that gets gummed up and doesn't move up and down freely. I had a M70 that nothing would engage and it was this mechanical part that was the problem. Once cleaned and lubed it worked fine
 

baddboybill

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Alberto said:
A Royce, can you see if the motor runs when you engage the play button? Does M80 have the same cassette transport as a M70? If so there is a mechanical plate/bar that is part of the auto stop on the front side just behind the head assembly that gets gummed up and doesn't move up and down freely. I had a M70 that nothing would engage and it was this mechanical part that was the problem. Once cleaned and lubed it worked fine
M80 has same/similar deck as M90 with dual motor and full auto soft touch features ;-)
 

BoomboxLover48

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Dec 3, 2010
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Alberto said:
A Royce, can you see if the motor runs when you engage the play button? Does M80 have the same cassette transport as a M70? If so there is a mechanical plate/bar that is part of the auto stop on the front side just behind the head assembly that gets gummed up and doesn't move up and down freely. I had a M70 that nothing would engage and it was this mechanical part that was the problem. Once cleaned and lubed it worked fine
Hi Alberto, M80 deck is similar to M90 with feather touch controls. Yes the main motor is running pushing the tape through the pinch roller and capstan when the take up reel won't engage. The auto stop is the magnetic wheel with sensor and will activate when the take up reel won't move. So the shut off takes place within fraction of a second.
 

BoomboxLover48

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It seems like an internal wheel is not engaging/ slipping that works with the take up axle. I need to remove the deck to the back of the set connect it and watch how the internal wheels engage in FF mode. There is no much space open to see the mechanism. This makes it hard. Also I don't want any shorting also.
 

cido

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Oct 1, 2014
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Provavelmente o problema esta nos fotos acopladores,sao 2 sensores de luz um emissor e um receptor,ficam em um suporte direcionados para aquela engrenagem que e dividida em varias partes preta e branca,verifique se não tem poeira dentro do suporte dos sensores,tambem pode testa-los como um diodo,e ate direcionando uma lusz para o receptor,ou ate jampando eles,caso não resolva verifique o CI VUC0002 que faz toda comutação das teclas.
 

Beosystem10

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:hmmm: Interesting, but that IC for the reel motor in the M80 is BA6208A according to the manual for the deck. I assume from that that it's auto reverse or is this serving a different purpose in there as the PC5 has the same chip and is most definitely not two way.

Did you sort this yet, Royce?
 

Cpl-Chronic

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May 14, 2012
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It is NOT auto reverse....I have an M80 & it works great but every once in a while you have to manually bump the flywheel or the carriage locks if it sits for too long unused. Hope you sort it out. That is a great radio that is definitely under-appreciated....

Cpl
 

BoomboxLover48

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Beosystem10 said:
:hmmm: Interesting, but that IC for the reel motor in the M80 is BA6208A according to the manual for the deck. I assume from that that it's auto reverse or is this serving a different purpose in there as the PC5 has the same chip and is most definitely not two way.

Did you sort this yet, Royce?
. Yes I did with the help of Arom (superlew). I had detailed pictures of it all in another thread. I can't find it now.
 

caution

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Mar 25, 2014
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cido said:
Provavelmente o problema esta nos fotos acopladores,sao 2 sensores de luz um emissor e um receptor,ficam em um suporte direcionados para aquela engrenagem que e dividida em varias partes preta e branca,verifique se não tem poeira dentro do suporte dos sensores,tambem pode testa-los como um diodo,e ate direcionando uma lusz para o receptor,ou ate jampando eles,caso não resolva verifique o CI VUC0002 que faz toda comutação das teclas.
Anyone catch this? I ran it through a translator.

"There could be a problem with the opto couplers. There are two sensors, a transmitter and a receiver, directed at the gear's black and white pattern. Make sure you don't have any dust inside the sensor supports. You can also can test them as a diode, shine light on the receiver, or even jumper them. If not this, then try checking the IC VUC0002. That controls all of the keys."
 

Beosystem10

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caution said:
Anyone catch this? I ran it through a translator.

"There could be a problem with the opto couplers. There are two sensors, a transmitter and a receiver, directed at the gear's black and white pattern. Make sure you don't have any dust inside the sensor supports. You can also can test them as a diode, shine light on the receiver, or even jumper them. If not this, then try checking the IC VUC0002. That controls all of the keys."
I ran it through one too :lol: , she's one of the tutors from the modern languages department at the campus where my department is also based. She's a (native Welsh speaking) polyglot who has Portuguese among the nine tongues she can speak commercially, none of which influenced at all my picking up on the function of that IC, which is designed primarily for auto reverse transport mechanisms but appears, from the PC5 manual, to be employed in some one-way decks too. It does appear later in the PC-55, maybe that was already going through CE testing and JVC had stocked up? It's the bit "controls all of the keys" that I was beached on as it's shewn in the manuals where it's for the reel motor.
 

caution

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Actually, the VUC0002-001 in the M60, M80, M90 and PC-5 does not support auto-reverse.

JVC didn't come out with auto-reverse boomboxes until 1982/3 with the PC-50/550, and that used a much larger IC which could also control the tape direction, dolby, counter mode/reset, sleep, memory, scan, etc.
 
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