Nope. I don't own a
rejuvinator. Anyone out there have one for sale that
works with amplifone's for a reasonably price?
Any chance this would actually help fix it or at least
diagnose the problem?
---
Hey John, I am by no means a
guru here, but do you have access to a rejuvinator?
They can tell you a few things about the condition of
the tube. Shorts being one of them.
Jordan B
On Sun, Jul
24, 2011 at 8:38 PM, John Huie <jehuie@sbcglobal.net>
wrote:
John
said, "I suspect that signal is your
problem though. Either it is not coming
from the board or it is not amplified by
the monitor chassis or
possibly the picture tube has a cathode
short and this negates the
Z-axis level completely. Not sure about
that last hypothesis though..."
Thank you John. I'm focusing on that
last part you said now because it makes
sense to me. I'm thinking that you mean
if I measure the voltages on either of
the 3 color signals from the SW CPU
board that will indicated my Z signal,
correct? Which is why I really need a
scope.
However, since both my SW boards do the
same thing and work fine in my other SW
game, they are clearly generating the Z
signal. Which leaves the other two
options.
It seems unlikely that all 3 colors
would be having problems amplifying by
the monitor chassis. And since the dot
in the middle is pure white, I think we
can negate that possibility. I'm not
sure this is true but I'm not getting a
lot of feedback so that's my best guess.
So that leaves me with a short in the
monitor as being my most likely
culprit. I tested for a short at the
pins and only found a short going from
the heater pins to pin 4. I'm still not
sure if that is ok or not though. And
if it's a problem, whether there is a
work around or if it means I'm screwed
and need a new tube.
Help. Pretty please!
John Huie wrote:
Just
to refresh...this
monitor on this Star
Wars works
good and the graphics
are all there and
everything but there's
a
constant bright dot in
the middle. If I turn
the brightness down
enough for the dot to
go away then I can't
see the other graphics
at
all.
Here's what I've tried
so far:
- Bought a whole slew
of components from Bob
Roberts to rebuild the
deflection board and
HV board
- HV is good.
- B+ is good.
- Adjusting color
drives doesn't help.
Brightness down and
the color
drives up still won't
let me turn down dot
enough to see graphics
well.
- I don't have any
spare parts to swap
in. I only have 6100
vectors
other than this.
- double checked
continuity from focus
block wiring, all
connections
under boots are good.
Good continuity back
to HV board and color
drives
on deflection board
are good.
- Pins on neck not
shorted to heater
pins. (Except pin 4
which isn't
used - could this be a
problem?)
- W jumpers are all
long gone.
- Resistors in neck
board/ring are good.
- Does same thing with
known working PCB set.
- Reflowed J103 and
tested continuity
along wires.
- Ground to neck
board/ring is good.
Still not sure how to
check Z signal. What
components should I be
looking at that are
common to all 3 colors
that could be causing
this?
Any other idea?
Thanks everyone. I'm
working on this for a
friend of mine and
just
about at the end of my
rope. |
Z-Signal is the brightness. What
sort of test equipment do you
have? A
'scope would be best - you could
check that the signal is
varying. An
AC setting on your multimeter
will give you an idea if there
is change
on that signal, but I do not
know what the result should be
for your
meter or situation. If someone
here has a voltmeter and can see
what
reading they get on the Z-level
when the board is on a set
screen test
that would help you figure out
if yours is working properly.
I suspect that signal is your
problem though. Either it is not
coming
from the board or it is not
amplified by the monitor chassis
or
possibly the picture tube has a
cathode short and this negates
the
Z-axis level completely. Not
sure about that last hypothesis
though...
John :-#)#
--
John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
Call (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, VideoGames)
www.flippers.com
"Old pinballers never die, they just flip out"
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