HP 8340b User Manual

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R31TP1:
CN
4530
MHz
M
and
N
Divide
Numbers
=
24
Test
Point
Frequency
=
3.333333
MHz
Figure B-13.
Signal
at
A31TP1
15.
Measure
the
frequency
at
A33J1
(the
counter
should
still
be
connected
in
the
configuration
described
in
step
7).
If
the
frequency
is
unstable,
proceed
to
step
18.
If
the
frequency
is
stable,
proceed
to
step 16.
NOTE:
If
the
frequency
out
of
A33J1
is
unstable,
it
is
still
possible to
check
the
operation
of the
M
Divider
on
the
A31
assembly.
To
do
this,
you
will
need
a
synthesized
source
(LO)
which
can
produce
a
376.000000
MHz
CW
signal
(for
example,
an
HP
8340A,
8341A,
8340B
or
8341
B).
Set the
LO
for
376.000000
MHz,
power
level
3
dBm,
and
connect
the
DUT's
10
MHz
REF OUTPUT
to
the
LO's
EXTERNAL FREQUENCY
STANDARD
input.
Disconnect
A31W2
from
A33J1
and
connect
the
source
to
A31W2.
With
this
input
signal,
A31TP2
should
measure
4
MHz
(with
an
M
Divide
number
of
24)
and
the
its
amplitude
should
be
similar
to
A31TP1.
16.
Using
the
frequency measured
in
step
15
and
the
following
formula,
calculate
the
frequency
which
should
appear
at
A31TP2
(Note:
the
divisor
of
6
in
the
following
formula
will
only work
when
the
M
Divide
Number
is
24):
FA31TP1=(400MHZ-Fs,epl5)/6
17.
Connect
Channel
1
of
the
oscilloscope
to
A31TP2
and
set
the
oscilloscope's
TIME/DIV
as
appro¬
priate
for
the
frequency
you
calculated
in
step
16.
Determine
if
TP2
is at the
frequency
calculated
in
step
16
and
the amplitude
is
similar
to
A31TP1.
If
the
signal
at
TP2
is
bad,
replace A31.
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|
CAUTION
j
In
the
M/N
Loop
adjustment
procedure,
you
will
be
connecting
a
DC
power
supply
to
TP1
(TUNE),
located
on
the
cover
of the
A33
M/N
output
assembly.
It
is
critical that
you
do not apply
a
positive
voltage
to
this
test
point.
Application
of
a
positive voltage
may
damage
the
tuning diodes
on
the
A32
VCO. Ensure
that
you
only
apply
a
negative
voltage
to TP1.
HP
8340B/41B
M/N
Loop
Assembly-Level
Troubleshooting

HP 8340b Specifications

General

Brand	HP
Model	8340b
Category	Inverter
Language	English