,.
�
If any work
has been performed
on
the SC 502
power supplies.
th
e
n the
+20
V.
-20
V and
+5 V
power
supplies must be checked
to be within 0. 2 V of
the
correct voltage
immediately after turn-on and
before the warm-up
period. See
step 1
for power
supply adjustments.
5.
A
l
l
o
w
1 5
mi nutes for
the
SC 502 to
warm-up
and
stabilize.
Adjustment
Procedure
NO TE
The
tabbed
foldout page labeled
"Adjustment
Locations "
contains
illustrations
showing
the
loca
tion of each
adjustment
in
this procedure.
1.
Adjust
+20 V ·
and
-20 V
Power Supplies
R925
and R947
(Trigger Circuit Board)
NOTE
Adjusting
the
+20 V and -20
V
power supplies
with
the 0. 1% dc
voltmeter
is
adequate
for oscilloscope
operation;
however.
if the
supplies are adjusted
this
way
the
output CAL peak-ta-peak
square-wave
voltage cannot be
guaranteed
to be within 1%. If a 1%
or
less calibrator
output amplitude
is
required.
then
the
+20
V
and
-20 V
power supplies
must
be
adjusted
with
a
dc voltmeter
having at least a 0. 01 %
accuracy.
Connect
the dc
voltmeter
between
the +20 V test poi nt
and the
ground
test
poi nt. Adjust +20
V.
R925 for
a
voltmeter
reading
of
+20 V ±0.06 V.
Disconnect
the
voltmeter
f
r
o
m the
+20
V
test
poi nt
and
connect
it
between
the
-20
V
test
poi nt and
the
ground
test
poi nt.
Adjust
-20 V, R947
for
a
voltmeter
readi ng
of
-20 V ±0. 1 V.
Disconnect
the
voltmeter.
2. Check +5 V
Power
Supply
Connect
the dc
voltmeter
between
the +5 V test poi nt
and
the ground test
poi nt.
Check
for
a
voltmeter
readi ng
of
+5.07 V
±0.08 V.
REV
MAY 1982
Calibration Procedure-SC 502
Adjustment
Procedure
3.
Adjust
Beam
Current
R8r3 (F
& I
Circuit Board)
�
To avoid
possible damage
to
the
crt phosphor. do
not allow a bright
spot
to remain stationary for an
extended
period
of
time within the viewing
area.
Connect
the positive
l ead of
the dc
voltmeter to
the
beam current
test
point (located
on mai n
circuit board)
and
the
voltmeter
negative lead
to
a
chassis
ground.
Set
the
voltmeter
to
measure about 2 V
ful l
scale.
Set
the SC
502
SECONDS/DIV
switch to A M P,
the
horizontal
POSITION
control
to
positi on
the spot
off
the
crt viewi ng
area, and the
I NTENSI TY
control
fully
clockwise.
Adjust
Beam,
R873
for a
v
o
l
t
m
eter
readi ng
of 0.40 V
±O.01
V.
Disconnect
the
voltmeter and turn
the
I NTEN
SITY
control
to its
midrange
position.
4.
Adjust Astigmatism
R899
(F
& I Circuit
Board)
Connect
a
test lead from CH
1
to
the
CAL connector.
Trigger the
osci lloscope
and
adj
u
st
FOCUS control R899
(Astigmatism) and
the
I NTENSITY
control
for
a clearly
focused
waveform.
Remove the test
lead.
5.
Adlust Trace Rotation R895 (F
& I Circuit
Board)
Set
the
SC 502
SECONDSIDIV
switch
to .5
m.
Position
the
SC
502
trace
to the center
horizontal
graticule
l ine.
Adjust
Trace,
R895 until
the
crt trace is
parallel
to the
center
horizontal
graticule
li ne.
6.
Adjust Geometry R897,
F & I Circuit Board
(Below
SN
B039280)
NO TE
Geometry adjustment
will c
a
u
se some
change
in
sweep timing.
Connect 0.5
ms time-markers
form
the
properly ter
mi
nated time
mark generator
to t he CH
1
i nput
connector.
Trigger
the display and
adjust CH
1
POSI TION
fully ccw.
Adj ust Geom
R897
for
mi nim um bow
or
ti lt of the
vertical
li nes, using
the vertical
graticule li nes
as the
reference.
T
h
e
adjustment
of
R897
may have to be a
compromise
to
bring
all
p
o
i
n
ts
within
the 0. 1
maj or
division
or
less
tolerance.
Discon nect the time-mark
generator.
4-1 1
Summary of Contents for SC 502
Page 1: ...SC 502 OSCILLOSCOPE ...
Page 2: ......
Page 9: ...SC 502 1878 1 The SC 502 Oscilloscope xi REV APR 1982 ...
Page 10: ...Verso Filler Page z z ...
Page 32: ...Verso Filler Page z z ...
Page 34: ...Verso Filler Page z z ...
Page 63: ...Section 6 SC 502 OPTIONS There are no options available at this time REV A APR 1980 6 1 ...
Page 84: ...Beam R873 C473 Ext Bal R535 CH 1 Vert Po R335 CH 2 Vert Pos R394 ADJUSTft TP980 5 ...
Page 125: ...REV MAR 1 984 ...
Page 126: ...SC 502 m m o ...
