VISUAL
TECHNOLOGY
INCORPORATED,
RAILROAD
AVENUE,
DUNDEE
PARK,
ANDOVER,
MA
01810
7.5
TV
MONITOR
PCB
REMOVAL
AND
INSTALLATION
In
order
for
the
TV
monitor
PCB
to
be
removed
it
is
necessary
to
remove
the
rear panel and
top
cover,
or
remove
the
rear panel and the logic
PCB.
Disconnect
the
cable connecting the
logic
PCB
and
the
TV
PCB
at
the
TV
end. Disconnect
the
yellow
and black
connector
and
the
blue and red
connector
connecting
the
TV
PCB
to
the
yoke
from
the
TV
PCB, and
the
flyback
transformer
cable
from
the
TV
PCB.
Unplug
the
connector
assembly
from
the
end
of
the
picture
tube. Squeeze and disconnect
the
black
wire
at
the
top
corner
of
the
picture
tube.
Slightly
tip
the
unit
and squeeze and press
four
plastic standoffs extending
through
the
base
plate.
Lower
the
unit
onto
its feet and remove
the
TV
PCB.
Remove
the
four
plastic standoffs
from
the
PCB
by
squeezing
the
locking
tab
and remove. Reinstall these
four
standoffs
into
the
base
plate.
Installing
the
TV
PCB
is
accomplished
by
pressing
the
PCB
into
place on
the
four
plastic
standoffs, pressing
the
board
until
the
locking tabs snap
into
place. Plug
the
CRT
socket
onto
the
CRT. Plug
the
flyback
connector
onto
the
board. Plug
the
yellow
and black
yoke
connector
onto
the
board adjacent
to
the
two
wire
wound
coils. Plug in
the
blue and red
yoke
connector
into
the
other
socket, and plug in
the
PCB
edge connector. Connect
the
black
wire
from
the
CRT
socket assembly
onto
the
ground finger tab
at
the
top
front
corner
of
the
CRT.
CAUTION
When installing
the
yoke
and
flyback
connectors observe orienta-
tion.
Each
of
these connectors can
be
installed backwards. When
they
are installed back-
wards considerably
more
force
is
required.
7.6
CRT
AND
FLYBACK
REMOVAL
AND
INSTALLATION
Before removing
the
picture
tube
it
is
necessary
to
discharge the tube.
With
an
insulated
handled
screwdriver
short
out
the
high voltage lead
to
the
tube.
Carefully
lift
the
top
edge
of
the
high voltage
connector
and insert
the
end
of
the
screwdriver.
Cause
the
screwdriver
shaft
to
touch
the
sheet metal bracket and
the
contact
of
the
high voltage
connector
simul-
taneously. The high voltage
connector
can
now
be
removed
by
rocking
it
while
pulling
it
up. Disco':lnect
the
yoke,
ground
wire, and
the
tube
socket assembly
as
described in section
7.5.
While
holding
the
lower
front
edge
of
the
picture
tube
in one hand, remove
the
four
mounting
screws, and remove
the
picture
tube. The
picture
tube
neck should
not
be
subjected
to
any pressure
or
shock. Store
the
picture
tube
on its face. The
fly
back trans-
former
can
now
be removed
by
unpluging
it
from
the
TV
PCB
and removing
two
mounting
screws. When installing
the
picture
tube
install
the
lower
two
screws first. Insert
the
ground
finger between
the
mounting
bracket
and the
topipicture
tube
mounting
tab. Install
the
top
two
screws and
connect
the
cables.
Be
sure
that
the
black ground
wire
is
installed!
7.7
TV
MONITOR
ADJUSTMENTS
Refer
to
Figure 7-3
for
the
location
of
the
adjustments.
Brightness
Control:
Adjust
it
so
that
the raster lines are visible.
Horizontal
Phasing
Control:
With
a line
or
more
of
data on
the
screen adjust
the
phasing
control
to
center
horizontally,
the
line
of
data
with
the
raster area.
Brightness
control:
Reduce
the
brightness
until
the
raster
just
disappears.
The
following
adjustments are best performed
with
a screen
full
of
the
letter
H.
Vertical
Size:
Adjust
so
that
the
total
height
is
6.00
±
.25
inches
(152.4
±
6.4
·mm)
41
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