HP 8340b User Manual

RF
Path
Assembly-Level
Troubleshooting
RF
path
troubleshooting
consists
of
checking
the
power
output
of
each microcircuit against
the
limits
specified
on
the
RF
path
block
diagram. Because
the
ALC
loop
is
open
during
power
measurements,
the
instrument
is
in
an
unleveled
condition.
NOTE: The
acceptable
power
limits
for
each
microcircuit
in
the
RF
path
are
dependent on
a
spec¬
ified
input
level.
The
minimum
input
levels
are
indicated
on
the
block
diagram.
1.
To
initialize
the
instrument, press
[INSTR
PRESET] [CW]
[XX.XX]
[GHz].
The
actual
frequency
depends
on
whether
you
wish to
check
the
low
or
high
band.
2.
To put
the
instrument
in
an
unleveled
condition, press
[XTAL]
leveling.
3.
Check the RF
path
frequency
dependence
across
all
bands
by
controlling
the
frequency
with the
front panel
knob.
Verify
the
full
frequency bands.
MP5
SCREW
(t
PLACES)
MPB
WASHER
(4. PLACES)
MP4
SCREW
(14
PLACES)
J2
MOD INPUT
FROM W24
AND
A62
MOTHERBOARD
J14-
3.7GH2
OUTPUT
TO
W9
AND
A9
LOW
BAND
MODULATOR J1
MP3
DONUT
RF1
SHIELD
(UNDER
COVER
PLATE)
MP7
NUT
(5
PLACES)
MP8
WASHER
(5
PLACES)
Figure
H-8.
A8
3.7
GHz
Oscillator
HP
8340B/41B
RF
Path
Assembly-Level
Troubleshooting

HP 8340b Specifications

General

Brand	HP
Model	8340b
Category	Inverter
Language	English