Operating instructions
LINE
.
The
LINE
position
connects
a
sample
of
the
power-
line
voltage
from
the
mainframe
to
the
trigger
circuit
.
Line
triggering
is
useful
when
the
input
signal
is
time-
related (multiple or
submultiple)
to
the
line
frequency
.
It
is
also
useful
for
providing
a
stable
display
of a
line-
frequency
component
in
a
complex
waveform
.
EXTERNAL
.
The
EXT
position
connects
the
signal
from
the
EXTTRIG
IN
connector
to
the
trigger
circuit
.
The
external
signal
must
be
time-related
to
the
displayed
waveform
for
a
stable display
.
An
external
trigger
signal
can
be
used
to
provide
a
triggered
display
when
the
internal
signal
is
either too
low
in
amplitude
for
correct
triggering
or
contains
signal
components
on
which
triggering
is
not
desired
.
It
is
also
useful
when
signal
tracing
in
amplifiers,
phase-shift
networks,
wave-shaping
circuits,
etc
.
The
signal
from
a
single point
in
the
circuit
can
be
connected
to
the
EXT
TRIG
IN
connector
through
a
probe
or
cable
.
The
sweep
is
then
triggered
by
the
same
signal
at
all
times
and
allows
amplitude,
time
relationship,
or
waveshape
changes
of
signals
at
various
points
in
the
circuit
to
be
examined
without
resetting
the
TRIGGERING
controls
.
The
-
10
pushbutton
attenuates
the
external
trigger
signal
by
a factor of
10
.
Attenuation
of
high-amplitude
external
trigger
signals
is
desirable
to
increase
the
effective
range
of
the
LEVEL
control
.
TRIGGER
SLOPE
The
TRIGGERING
SLOPE
switch
(concentric
with
the
TRIGGERING
LEVEL
control)
determines
whether
the
trigger circuit
responds
on
the
positive-
or
negative-going
portion of
the
trigger
signal
.
When
the
SLOPE
switch
is
in
the
(+)
(positive-going)
position,
the
display
starts
on
the
positive--going
portion
of
the
waveform
(see Fig
.
1-4)
.
When
several
cycles
of
a
signal
appear
in
the
display,
the
setting
of
the
SLOPE
switch
is
often
unimportant
.
However,
if
only a certain portion of
a
cycle
is
to
be
displayed, correct
setting
of
the
SLOPE
switch
is
necessary
to
provide
a
display
that
starts
on
the
desired
slope
of
the
input signal
.
TRIGGER
LEVEL
The
TRIGGERING
LEVEL
control
determines
the
voltage
level
on
the
trigger
signal
at
which
the
sweep
is
triggered
.
When
the
LEVEL
control
is
set
in
the
+
region,
the
trigger
circuit
responds
at a
more
positive
point
on
the
trigger
signal
.
When
the
LEVEL
control
is
set
in
the
-
region,
the
trigger
circuit
responds
at
a
more
negative
point
on
the
trigger
signal
.
Figure
1-4
illustrates
this
effect
with
different
settings
of
the
SLOPE
switch
.
To
set
the
LEVEL
control,
first
select
the
TRIGGERING
MODE,
COUPLING,
SOURCE,
and
SLOPE
.
Then
set
the
LEVEL
control
fully
counterclockwise
and
rotate
it
clockwise
until
the
display
starts
at
the
desired
point
.
HORIZONTAL
SWEEP
RATES
The
TIME/DIV
switch
provides
calibrated
sweep
rates
from
5
seconds/division
to
10
nanoseconds/division
in
a
1-2-5
sequence
.
The
VARIABLE
TIME/DIV
control
must
REV
A
MAR
1981
be
in
the
calibrated position
and
the
MAG
switch
set
to
X1
to
obtain
the
sweep
rate
indicated
by
the
TIME/DIV
switch
.
However,
the
mainframe
CRT
readout
will
display
the
appropriate
sweep
rate
.
The
VARIABLE
TIME/DIV
control
includes
a
two-position
switch
to
determine
if
the
sweep
rate
is
calibrated,
or
uncalibrated
.
When
the
VARIABLE
control
is
pressed
in,
it
is
inoperative
and
the
sweep
rate
is
calibrated
.
When
pressed
and
released
outward,
the
VARIABLE
control
is
activated
for
uncalibrated
sweep
rates,
to at
least
the
sweep
rate
of
the
next
slower
position
.
A
calibrated
sweep
rate
can
be
obtained
in
any
position
of
the
VARIABLE
control by
pressing
the
VARIABLE
control
.
This
feature
is
particularly
useful
when
a
specific
uncalibrated
sweep
rate
has
been
obtained
and
it
is
desired
to
switch
between
calibrated
and
uncalibrated
displays
.
TIME
MEASUREMENT
When
making
time
measurements
from
the
graticule,
the
area
between
the
second
and
tenth
vertical lines
of
the
graticule
provides
the
most
linear
time
measurements
(see Fig
.
1-5)
.
Position
the
start
of
the
timing
area
to
the
second
vertical
line
and
adjust
the
TIME/DIV
switch
so
the
end
of
the
timing
area
falls
between
the
second
and
tenth
vertical
lines
.
SECOND-VERTICAL
TENTH-VERTICAL
LINE
LINE
t
v
SWEEP
MAGNIFICATION
-TIME
MEASUREMENT
AREA
Operating
Instructions-71387
+44-+-
C
1752-06
Figure
1-5
.
Area
of
graticule
used
for
most
accurate
time
measurements
.
The
sweep
magnifier
can
be used
to
expand
the
display
by
a
factor of
10
.
'The
center
division
of
the
unmagnified
display
is
the
portion
visible
on
the
crt
in
the
magnified
form
(see
Fig
.
1-6)
.
The
equivalent
length
of
the