HP 8341b User Manual

FREQUENCY
(14)
If
the
UNLK
annunciator
is
not
on,
and
the
RF
output
signal
frequency
is
incorrect,
refer
to Section
IV
Performance
Test,
Frequency
Range
and
CW
Mode
Accuracy.
This
test
checks
all
of the divider
bits
that
program
the
various
phase
lock
loops.
The
test
indicates which
phase
lock
loop
is
causing
the
problem
and
which
bit
or
bits
are incorrect.
After
you
isolate
the faulty
loop,
refer
to
the
appropriate
functional
group
troubleshooting.
POWER
(15)
The
RF
output
should
meet
the
specifications
for
maximum
leveled
power,
power
accuracy,
and
flatness.
Maximum
Leveled
Power
For
problems
related
to
maximum
leveled
power,
refer to
UNLEVELED
ANNUNCIATOR.
Flatness
NOTE:
Before performing
the
following
procedure,
use
the
SHIFT
M4
diagnostic
test
to
help
isolate
the
cause
of
an incorrect
power
condition.
1.
The
flatness
adjustments
in
Section
V,
Adjustments, improve
overall
flatness
by
varying
the offset
and
slope correction
factors.
If
the
frequency response
has
large
variations,
the
problem
is
proba¬
bly
in
the
associated
RF
path.
Refer to
the
RF
section
functional
group.
2.
If
the
RF
power
level
is
low
at
10
MHz
and
increases
with
frequency,
suspect
the
RF
output
connector.
This
connector contains
a
series
capacitor
that
can
exhibit
this
symptom.
To verify
that
the
problem
is
the
RF
connector:
a.
Remove
the
front
panel (see
the
front
panel
—
rear
panel
functional
group).
b.
Disconnect
the
SMA
cable
to the
RF
connector,
and
remove
the
RF
connector.
c.
Measure
the
power
level
at
the
cable.
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|
CAUTION
j
Be
extremely careful when
disconnecting
or connecting an
SMA
cables
from
a
mating
3.5
mm
connector
(RF
attenuator).
The
SMA
cable
center
conductor
must
align
with
the
3.5
mm
connector
center
conductor.
If
there
is
any
axial
force on
the
cable when
disconnecting
the
SMA
fitting,
the
3.5
mm
connector center
conductor
can
be
damaged.
Remove
any
axial
force on
the
cable
by
first
disconnecting
the
end
of
the
cable
that
does
not
mate
with
the
3.5
mm connector,
or
by
removing
the
mounting
screws
of
the
device
having
3.5
mm
connector.
HP
8340B/41B
Assembly-Level
Service
Overall
Instrument
Troubleshooting
A-43

HP 8341b Specifications

General

Frequency Range	10 MHz to 20 GHz
Spurious Output	≤ -60 dBc
Input Impedance	50 Ω
Output Impedance	50 Ω
Operating Temperature	0 to 55 °C