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Go Video Servo Problem
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Sofie
Nov 7, 1999, 3:00:00 AM11/7/99
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John:
What were the results of your scope troubleshooting on the servo circuits?
I assume we are talking about the drum servo from your description of the
symptoms. Are you getting a good signal pulse from the drum sensor? Is the
error signal OK in the drum phase loop? How about bad drum bearings? Open
motor windings?
Dan Sofie
Electronics Supply & Repair
============================================
What were the results of your scope troubleshooting on the servo circuits?
I assume we are talking about the drum servo from your description of the
symptoms. Are you getting a good signal pulse from the drum sensor? Is the
error signal OK in the drum phase loop? How about bad drum bearings? Open
motor windings?
Dan Sofie
Electronics Supply & Repair
============================================
JohnAce <joh...@aol.com> wrote in message
news:19991107195137...@ng-fu1.aol.com...
> I have a Go Video in for repair. Model Number GV3020. The problem is that
Deck
> 1 pulsates in playback mode. Deck 2 works good.Seems I can keep the
cylinder at
> a steady state. I tried swopping partsf from one side to the other ( IC's
> Capacitors etc) but can't correct the problem.. Any Guesses?
JohnAce
Nov 8, 1999, 3:00:00 AM11/8/99
to
JohnAce
Nov 9, 1999, 3:00:00 AM11/9/99
to
II don't have a manual for this but one is on the way. I do know for sure it's
m not the lower cylinder or bad bearing or an open winding in the motor. I
swapped them and the problem still stayed to deck one. All I can tell you is
that the voltage on two of the pins a flucutaing around 2.5 volts compared to
the other cylinder which is a stable 2.5 volts.
m not the lower cylinder or bad bearing or an open winding in the motor. I
swapped them and the problem still stayed to deck one. All I can tell you is
that the voltage on two of the pins a flucutaing around 2.5 volts compared to
the other cylinder which is a stable 2.5 volts.
JohnAce
Nov 10, 1999, 3:00:00 AM11/10/99
to
I have swopped the 2 cylinders and the IC on the board and it still stays on
Deck 1.
I have no manual on this yet so I'm guessing . I do have a steady 2.5 volts on
2 pins on the connctor as the other connector is flucuating and not steady. I
will have to look some more to find out why.
Deck 1.
I have no manual on this yet so I'm guessing . I do have a steady 2.5 volts on
2 pins on the connctor as the other connector is flucuating and not steady. I
will have to look some more to find out why.
THANKS
Sofie
Nov 10, 1999, 3:00:00 AM11/10/99
to
John Ace:
Did you get your scope fired up yet? Per our previous posts you were going
to look at the signal pulse from the drum sensor...........is it there?
Also, how does the error signal look on the drum phase loop?
Since the drum servo and capstan servo are interdependent.........did you
make sure that the capstan servo is locked? Scope the error signal to be
sure. Also check the audio.......if you put in a test/alignment tape with
standard tone.......is it playing back right on, low (slow), high (fast), or
is the capstan servo hunting.
Be sure the chip you replaced is the only one that affects what you are
chasing......there might be other semiconductors and components that are
causing the problem........to be able to see what is going on or not going
on, your scope will help provide the necessary insight.
Dan Sofie
Electronics Supply & Repair
========================================
Did you get your scope fired up yet? Per our previous posts you were going
to look at the signal pulse from the drum sensor...........is it there?
Also, how does the error signal look on the drum phase loop?
Since the drum servo and capstan servo are interdependent.........did you
make sure that the capstan servo is locked? Scope the error signal to be
sure. Also check the audio.......if you put in a test/alignment tape with
standard tone.......is it playing back right on, low (slow), high (fast), or
is the capstan servo hunting.
Be sure the chip you replaced is the only one that affects what you are
chasing......there might be other semiconductors and components that are
causing the problem........to be able to see what is going on or not going
on, your scope will help provide the necessary insight.
Dan Sofie
Electronics Supply & Repair
========================================
JohnAce <joh...@aol.com> wrote in message
news:19991110185529...@ng-fv1.aol.com...
GlobalBilG
Nov 11, 1999, 3:00:00 AM11/11/99
to
could you let me know what you find out please ? There are a few of these units
in my area.
in my area.
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