Tektronix 2247A

Basic Applications
the
display
reduces
the
users’
ability
to
make
an
accurate
reference
setting.
(Triggering
on
the
negative
slope
of
the sine
wave
may
position
the
waveform
correctly
within
the
graticule
area
for
ease
in
measure-
ment
when
viewing
a
single
cycle
of
the
reference
signal.)
5.
Press
the
TIME
button
to
display
the
Cursor
measurement
choices.
6.
Select
J
PHASE
J.
A
second-level
phase-measurement
menu
Is
then
displayed
with
three
cholces:
«+
PHASE
-x3
to
continue
the
phase
measurement,
I
SET
360°>1
to
set
the
360
degree
reference,
and
360°
TRACKS
A
TRIG
PERIOD,
which
is
an
alternative
to
using
k-
SET
360°-1.
When
360°
TRACKS
A
TRIG
PERIOD
Is
selected,
the
phase
measurement
will
alternate
between
a
C/T
measurement
of
the
A
trig
period
and
the
delta
Time
measurement.
7.
Assume
the
present
reference
setting
Is
not
correct
(if
It
were,
selecting
\¢
PHASE
|
again
continues
the
measurement
using
the
present
reference
value).
Press
l¢
SET
360°]
to
activate
the
ref-
erence
setting
function.
The
position
of
the
displayed
cursors
when
k-
PHASE
-|
Is
again
selected
defines
the
full
waveform
period
(360
degrees).
8.
Position
the
first
vertical
cursor
to
the
point
that
the
reference
waveform
crosses
the
center
horizontal
graticule
line
In
the
positive
direction
(see
Figure
5-5A).
The
Horizontal
POSITION
control
may
be
used
as
necessary
to
center
the
waveform
period
in
the
viewing
area.
9.
Position
the
delta
cursor
to
the
second
positive
crossing
of
the
center
horizontal
graticule
line
by
the
reference
waveform
as
shown
In
Figure
5-5A.
10.
Select
#-
PHASE
-
to
continue
with
the
phase
measurement:
the
ref-
erence
value
will then be
saved.
11.
Apply
the
phase-shifted,
sine-wave
signal
to
be
measured
to
the
CH
2
Input
connector
using
a
10X
attenuator
probe,
and
turn
CH
2
VERTICAL
MODE
on
to
display
the
signal.
12.
Set
the
VOLTS/DIV
and
VOLTS/DIV
VAR
controls
to
match
the
ampill-
tude
of
the
phase-shifted
signal
to
that
of
the
reference
waveform
as
shown
In
Figure
5-5B.
Use
the
VERTICAL
POSITION
control
as
necessary
to
align
the
two
waveforms
vertically.
13,
Reposition
the
second
cursor
to
the
first
positive
crossing
of
the
phase-
shifted signal,
and read
the
phase difference.
2247A Operators
fe
r
er
EO