HP 8753D - Page 80

3.
Substitute a
thru for
the device
and perform
a response
calibration by
pressing:
4
CAL
5
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CALIBRATE MENU
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RESPONSE
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THRU
4. Reconnect
your test
device.
5. T
o better
view the
measurement
trace
,
press:
4
SCALE
REF
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AUTO
SCALE
Notice
that
in
Figure
2-29
the
SA
W
lter
under test
has considerable
phase shift
within
only
a
2
MHz
span.
Other
lters
may
require
a
wider frequency
span to
see the
eects
of
phase
shift.
The
linearly
changing
phase
is
due
to
the
device's
electrical length.
You
can measure
this
changing
phase
by
adding
electrical
length (electrical
delay) to
compensate for
it.
Figure
2-29.
Linearly
Changing
Phase
6.
T
o
place
a
marker
at
the
center
of
the
band, press:
4
MARKER
5
and
turn
the
front
panel
knob
or
enter
a value
from the
front panel
keypad.
7.
T
o
activate
the
electrical
delay
function,
press:
4
MARKER F
CTN
5
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MARKER
!
DELAY
This
function
calculates
and
adds
in
the
appropriate
electrical delay
by taking
a 6
10%
span
about
the
marker
,
measuring
the 1
 ,
and computing
the delay
as the
negative of
1

/1frequency
.
Making Measurements 2-31