. - '
I n
the
A C
c
o
u
p
l
i
n
g position, the
d c
c
omp
o
n
e
nt
of
t
h
e
signal
is
blocked
by
a
c
a
p
a
c
i
t
o
r
i n
the I nput
circuit.
The
l ow-frequency
-3
dB
p
o
i n
t
in
t
h
e
AC
positi on
is
a
b
o
u
t
1 0 Hz.
Therefore,
some low-frequency attenuation can
be
expected
near
this
f
r
e
qu
e
n
c
y
limit.
Attenuation
i n
the
form
of
w
a
v
e
f
o
r
m
tilt
will also appear in
square
w
ave
s
that have
low-frequency
c
o
m p
o
n
en
ts
.
The
AC
coupl i ng position
provides the best
display
of
signal s
with
a
dc
com ponent
that is
m uch l
a
r
g
e
r
than the
ac component.
The
DC
c
o
u
p
li
ng position can
be
u
s
e
d
for most
applications.
This
p
o
s
i
t
i
o
n
allows measurement
of
the dc
com ponent of
a
s
i
g
na
l
and m ust
be
used
to
d
i
s
pl
a
y
S
i
g
n
a
l
s
below
about
50 Hz
to
a
vo
i
d
the
a
tt
e
n
u
a
t
i
o
n
that would
occur
u
s
i
n
g
ac
coupli ng.
The
GND
positi on
provides
a ground
reference
at
the
i nput
without
the
need
to
externally ground the
probe.
The
signal applied
to
the
p
r
o
b
e
is
i
n
t
e
r
n
a
l
l
y
disconnected
from
the i nput c
i
r
c
u
i
t
and connected to
ground
through
a
1 MO
resistor. The am pl ifier input
c
i
r
c
u
i
t
is held at g
r
o
u
n
d
potential.
In
the
GND
position, connecti ng the
input
S
i
g
na
l
to
ground
through
a
1 MO
resistor
f
o
r
m
s
a
prechargi ng
network.
This
network allows the
i
n
p
ut
coupling capacitor
to
charge
to
the average dc voltage
level
of the
s
i
g
n
a
l
applied
to
the probe.
S
i
n
c
e
this
takes
place
i n
t he
GND
position o f
the AC-GND-DC
switch,
a n y
large
voltage
transients aCCidental ly g
e
n
e
r
a
t
e
d
will not
be
applied
to
the
amplifier
input.
The
pre-charge
network
also p
r
o
v
i
d
e
s
a
measure
of
p
r
o
t
e
c
t
i
o
n
to
the external ci rcuit
by reducing
the
current levels
that
can be
drawn from
the
external
circuitry
during capacitor charging.
The
f
o
l
l
o
w
i n
g
procedure
should be
u
s
e
d
whenever the
pr
o
be
ti p
is
connected
to
a
Signal source having
a diff
e
r
e
n
t
dc
level
than that previously ap
p
lie
d
.
1 . Be
f
o
r
e
connecting
the p
ro
b
e
ti p to
a Si gnal
s
ourc
e
,
set
the
AC-G N D-DC
switch
to
GND.
2.
T
o
u
c
h
the
probe tip
to
oscill oscope chassi s
g
r
o
u
n
d
.
Wait
s
ev
e
ra
l
seconds
for the
i
n
p
u
t
cou pling
capacitors
to
discharge.
3.
Connect the p
r
o
b
e
tip to
the
s
i
g
n
al
s
o
ur
c
e.
4.
Wait several seconds
for
t
h
e
I nput c
o
u
pl
i
n
g
c
ap
a
cit
o
r
to
charge.
5.
Set
the
AC-
G
N
D-
DC
switch to
AC.
The display
will
remai n
on
screen so
t
he
ac
c
o
m p
o
ne
n
t
of
the
signal
can
be measured
in
the
normal
manner.
@ MAY
1 980
OperaUng
Instructlons-SC 502
Trigger Source
Internal
Triggering.
For
m ost
applications
t
h
e sweep
can
be
tri ggered
internally.
I n
the
CH
1
and
CH
2
pOSitions
of
the
trigger
SOURCE
switches, th
e
trigger
si gnal
is
obtai ned from
t
h
e vertical deflection
system.
For
dual
trace
displays. s
p
e
ci
a
l consi derations
m
u
s
t
be
m ade
to
provide
the
correct
display.
Refer to
the Dual-Trace
Operation
explanation in the
Vertical
Display
portion
of
the Basic
O
p
e
r
a
t
i
n
g
i nstructions
for dual-trace tri ggering
information.
Un. Triggering.
LI N E
p
o
s
i
t
i
o
n
of
the
SOU RCE
s
w
i
t
c
h
is
achieved by
simultaneously
d
e
p
r
es
s
i n
g
the
CH
1
and
C H
2
b
utt
o
n
s
.
The
LI N E
position
connects
a
sam pl e
Of
t
h
e
power-line voltage to the
i nput
of
the Tri gger
generator.
Li ne
triggeri ng
is
useful
when the i nput
s
i
g
n
a
l
is
time
r
e
l
a
t
e
d (multiple)
to the line frequency.
I t
is
al so usef u l for
providing
a
stable display
of
a li ne-freq uency
com ponent
i n
a
c
o
m
p
l
e
x
waveform.
External
Triggering.
An
external signal connected
to
the
EXT IN
c
o
n
n
ect
o
r
can be used
to
tri gger
the
sweep
in
the
EXT
p
O
Si
t
i
o
n
of
the
SOU RC E
switch. The
external
Signal must
be
time-related
to
the
d
i
s
p
l
a
y
e
d
signal
f
o
r
a
stable d
i
s
p
lay
.
An external trigger signal
can
be
used
to
p
r
o
vi
d
e
a
triggered display
when
t
h
e
i nternal si g nal is
too
l ow
in
a
m
p
l
i
t
u
d
e
for
correct
tri ggeri ng, o
r
contai ns
undesirable
Signal com ponents.
It
is
also
useful
when
s
ign
a
l traci ng
in
a
m p
l
i
f
i
e
r
s
,
phase-shift
networks,
wave
shapi ng
circuits,
etc.
The signal
from
a
S
i
n
g
l
e
poi nt in
the
c
irc
u
i
t under test
can be
connected
to the
external
tri gger
i
n
p
ut
co
n
n
e
c
t
o
r
t
hr
o
ug
h a
ca
b
l
e
or
signal
probe.
The
s
w
ee
p is
th
e
n
triggered by
the
same
signal
at
all
times and
allows
am
pl
i
t
u
d
e
,
time
relationshi p,
or waveshape
changes
of
s
i
gn
a
l
s
at various
pOi nts
in
the circuit
to
be
exami ned
without
reseUing
t
h
e trigger
controls.
Trigger Coupling
Two methods of coupling
the
trigger
signal
to
the
trigger
circuits
can
be
sel ected
with the tri gger
COUPLING
switches.
Each
method
permits s
e
l
e
ct
i
o
n
or
rejection of certai n f
r
eq
u
e
n
c
y
com ponents
of
the tri gger
s
ig
n
a
l
to
obtai n
s
e
l
ec
t
i
v
e
triggering.
AC Coupling.
The
AC
p
o
s
iti
o
n
blocks the
dc
com po
nent
of
the
trigger
Signal.
Signals
with
low-frequency
components below
about
50 Hz
are
aUenuated.
I n
general ,
ac coupling
can be
u
s
e
d for most
applications.
Ho
w
e
v
e
r
,
if the trigger
s
ig
na
l
contai ns unwanted
frequen
cy
components,
t
h
e
LF
REJ
COUPLI NG
switch
may
p
r
o
v
i
de
a
beUer d
i
s
pl
a
y
.
Low-Frequency RejeCt.
-
The
IF REJ
p
o
s
i
t
i
o
n
passes
al l
high-frequency
s
i
g
n
a
l
s
above
about
5
kHz.
Dc is
rejected
and
s
i
g
n
al
s
below
about
5
kHz
are
aUenuated.
When
2·7
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 ...
