12.
Press
CAL
SEQ
4
ST
ART
5
on
the
preselector.
Selected
com
b
teeth
are
measured
b
y
the
sp ectrum
analyzer
section.
An
y
v
ariation
b et
w
een
the
measured
com
b
to
oth
amplitude
and
the
v
alue
stored
in
the
preselector
section
is
corrected
b
y
an
in
ternal
preselector
section
gain
adjustmen
t.
The
CAL
SEQ
LED
ashes
while
the
calibration
routine
runs.
Note
After
calibration,
the
CAL
SEQ
LED
stays
on,
indicating
that
the
system
is
calibrated
o
v
er
the
curren
t
frequency
range.
If
the
frequency
range
is
increased
b ey
ond
the
calibrated
frequency
range,
the
light
turns
o
to
indicate
an
uncalibrated
state.
Ho
w
ev
er,
the
CAL
SEQ
light
do es
not
turn
o
when
parameters
other
than
the
frequency
range
(start
and
stop
frequency)
are
c
hanged.
Therefore,
y
ou
may
ha
v
e
an
uncalibrated
state
while
the
CAL
SEQ
light
is
on.
Be
sure
the
receiv
er
is
calibrated
for
the
curr
ent
instrumen
t
settings.
13.
Disconnect
the
preselector
section's
com
b
generator
output
and
reconnect
the
signal
source
to
receiv
er
INPUT
2 .
Use
the
same
cable
during
measuremen
ts
that
y
ou
used
for
calibration;
the
system
has
comp ensated
for
the
loss
in
this
cable.
Remem
b er
to
accoun
t
for
the
losses
in
the
calibration
cable
if
y
ou
do
not
use
that
same
during
the
actual
measuremen
t.
Using
other
cables
may
in
tro duce
an
amplitude
error.
14.
Set
the
sp ectrum
analyzer
span
to
1
MHz
and
cen
ter
frequency
to
100
MHz.
HP
8572A
EMI
Receiv
er
User's
Guide
Making
Typical
Measurements
4-11