Panasonic NV-F65 thinks it has a tape inserted

[Mike Wilson]

My NV-F65 VCR has come into a state where it thinks there is a tape cassette
loaded even though there isn't. It also powers down a few seconds after
turning it on. It all started after a cassette had got stuck and I had to
force it out, tape was still stuck round one of the arms inside so had to
cut it.

This is what happens:
- vcr is plugged into power but turned off, displays clock and "tape
inserted" symbol
- I press power button
- video head starts spinning
- a servo on the right hand side clicks
- cassette wheel rotates half a lap to tension tape (which isn't there)
- after a few seconds the vcr powers down

If I insert a tape (have to push it all the way in as the vcr doesn't "grab"
it for me) this happens:
- the tape is pulled down in position
- a black arm moves the tape over to the audio head
- the arms that should wrap the tape around the video head are not moving
- the audio arm brings the tape back
- the tape is ejected
- the vcr powers down

So there seems to be some kind of mechanical problem. Maybe there is some
stuck sensor that I need to give a push?
I would really appreciate any help on this...

Mike

 

[mo]

My NV-F65 VCR has come into a state where it thinks there is a tape cassette
loaded even though there isn't. It also powers down a few seconds after
turning it on.

Never really popular with technicians the old G-Mechanism.

Enjoy the frustrations of repairing or spend under $200 AUS to replace
with a new unit with more features.

 

[eddumweer]

On g-deck check the mode select switch and timing of the mechanism

Greetings PP

 

[Mike Wilson]

Hi, and thanks for your replies. So you're saying that it isn't just a
simple
"stuck sensor" problem, and need lengthy repairs?
Where do I find the mode select switch? (sorry, I don't have any
schematics for the unit)
Cheers / Mike

 

[eddumweer]

The modeselect switch is located on the deck-top on the right back site
viewing from the front.

Here you find a picture of it http://www.donberg.ie/descript/2/20204.htm

The mode select swtich reads out the position of the deck, example play,
rewind, fast rewind and so on.
Take care of the timing of the machine. There are marks on several wheels
and also the cassettecomparment is timed to the g-deck.

If a switch is not available at once, try some not to aggressive
electracleaner in the switch for checking if it works.

Als check the pcb where the switch is mounted on for open circuit towards
the cable connector.

Greetings Peter

 

[Mike Wilson]

Thanks! I've located the mode switch and done some more tests (not
disassembling anything yet):

I can see the mode switch wheel is standing still when I am just
powering on the unit. Other wheels on the right hand side "below
the floor" move a little and then stop - the faint sound gives me
a feeling that something is stopping them from moving more.

When inserting a tape I can see that the mode switch wheel is
rotating.
A few times when inserting the tape the unit seems to do a more
complete initialization and the video head arms are moving, but
then I hear loud clicking noises as from two wheels sliding on
each other. I can see the mode wheel standing still but vibrating
in sync with the clicks, as if something that wants to move is
stuck. Do you have any idea why this happens, doesn't seem
directly related to the mode switch...?

I shot a video of this behaviour showing first the "direct eject"
case and followed by the "full init" case. Would you please have a
look at it?
http://194.236.117.66/nvf65_hi.wmv (12MB)
http://194.236.117.66/nvf65_lo.wmv (2.5MB)

Cheers
Mike

 

[eddumweer]

Looks like a timingproblem, for the manual see
http://www.eserviceinfo.com/downloadsm/6054/Panasonic_NV-F65.html

Hope you can do anything with it.

Greetings Peter

 

[Mike Wilson]

[Sory for not replying until now; for some reason your last
message never appeared on my Usenet server]

I downloaded the manual and I mainly found schematics for
the electronic circuits. Do you know if there is a manual
to be found for the mechanics? (So I can get a hint of
what wheels should be aligned in what way, and so on...)

Anyway, from the current manual I will be able to check if
the mode switch is connecting the right pins for its current
state, I'll check that this weekend!

Thanks for your help
Mike