Page 84
DC CALIBRATION
POWER SUPPLY CIRCUIT BOARD
( L( Place
the
POWER
switch
in
the
ON position.
Turn
the
front
panel
INTENSITY control fully
counterclockwise.
Refer
to
Pictorial 5-3 (Illustration Booklet, Page 24) for
the
following steps.
(.
/(
Adjust
the
INTEN BIAS control clockwise (as
viewed
from
the
front panel)
until
the
trace
is
visible (the trace
may
already
be
visible).
Then
adjust
the
control
back
counterclockwise
until
the
trace
disappears.
(
U'
Adjust
the
ASTIG control:
Turn
the
INTENSITY control
clockwise
until
the
trace
appears
.
Turn
the
TIME/CM
switch
to
the
EXT IN
x 10 position.
Center
the
spot
with
the
HORIZ POS con-
trol.
Adjust
the
ASTIG
control
and
front
panel
FOCUS control
until
the
dot
is small,
round
·,
and
as clear as
possible
.
HORIZONTAL CIRCUIT BOARD
[
vJ
Use
the
front
panel
HORIZ POS control
and
!
center
the
spot
on
the
screen.
( )
Connect
the
negative
voltmeter
lead
to
the
/
chassis
of
the
Oscilloscope.
'(
/ )
Set
the
voltmeter
to
measure
1.5 volts
DC.
Refer
to
Pictorial 5-4 (Illustration Booklet, Page 24) for
the
following steps.
NOTE:
In
the
following steps,
when
a step calls for
an
adjustment
of zero volts,
make
the
adjustment
to
zero
volts
±50
millivolts.
Touch
the
voltmeter
probe
to
TP1
and
adjust
the
ZERO ADJ control for zero volts.
(
1'
Measure
the
voltage
at
TP2
and
adjust
the
INPUT ZERO control for zero volts.
v-('
Set
the
voltmeter to
measure
5 volts
DC
.
(
~
easure
the
voltage
at
TP3
and
record
the
read-
i
ide
this
step.
It
should
be
approximately
5 volts
.8
to
5.2).
Measure
the
voltages
at
TP4
and
TP5. Adjust
the
front
panel
HORIZ POS control
until
both
test
points
are equal.
Then
adjust
the
BIAS
AD]
control
until
the
test
point
voltages equal the
meter
reading
you
recorded
in
the
previous
step.
VERTICAL CIRCUIT BOARD
( /
set
the
voltmeter
to
measure
1.5 volts
DC.
Refer to Pictorial 5-5 (Illustration Booklet, Page 24) for
the
following steps.
(
~
Measure
the
voltage
at
TP6.
Then
adjust
the
Y2
DC
BAL control for zero volts.
(
~
Measure
the
voltage
at
TP7
and
adjust
the
Yl
·
DC
BAL control for zero volts.
[J
Placethefrontpanel
Yl,
Y2,
CHOP,ALTswitch
in
the
ALT position.
Two
traces
should
be
on
the
screen.
If
necessary,
use
the
Yl,
or
Y2
POS
controls
to
position
the
traces
near
one
another.
(
vf
Rotate
the
Yl
VARIABLE control fully counter-
clockwise. Place
your
finger
on
the
CRT
to
mark
the
new
location
of
the
Yl
trace
line
if
it
moved.
Return
the
Yl
VARIABLE control
to
its
CAL
position.
Then
adjust
the
Yl
DC
BAL control to
move
the
Yl
trace
to
the
location
marked
by
your
finger. Repeat
this
procedure
as
many
times as necessary
until
the
trace
no
longer
moves
when
you
rotate
the
Yl
VARIABLE con-
trol.
If
the
trace
did
not
move
initially,
no
ad-
justment
of
the
DC
BAL control is
needed.
(
1'
In
the
same
manner,
check
the
Y2
trace
line
and
adjust
the
Y2
DC
BAL control.
To Next Page
Loading...
