Agilent Technologies HP 83711B Service Guide

Troubleshooting
8. Change
the oset
synthesizer frequency
to the
failing
frequency
or
frequencies
indicated
by the
self test
using
the
oset
freq
function.
For
example,
to
set
the
oset
synthesizer
frequency
to
13.000
MHz:
a. Press
4
SPCL
5 .
b. Press
4
63
5 on
the numeric
keypad,
then
terminate
the
entry
by
pressing
4
Hz
5 (ENTER).
c.
Press
4
13
5
on
the
numeric
keypad.
d.
Press
4
MHz
5
.
9.
V
erify
that
the
measured
frequency
is
exactly
as
shown
in
the
following
table
plus-or-minus
one
count
and
that
the
voltage
at
J3
pin
2
remains
at
a
TTL
high
level.
If
the suspected
frequency
or
frequencies
as
well
as
the
voltage
level
is
correct,
continue
with
the
next
step
.
If
a
suspected
frequency
or
the
TTL
voltage
level
is
incorrect,
replace the
YO
loop
and
oset
synthesizer
assembly
.
Oset
Synthesizer
Frequency
Oset
Synthesizer
Frequency
13.000
MHz
26.500
MHz
14.749
MHz
13.000
MHz
14.750
MHz
26.500
MHz
19.499
MHz
19.500
MHz
19.500
MHz
19.499
MHz
10.
Disconnect
the
frequency counter
from
J1
and
connect
an
oscilloscope
to
it.
11.
V
erify
the output
levels
of
the
signal
at
J1
at
the
suspected
oset
frequency
.
They
should
be
TTL
levels
.
If the
output
levels
are
at
TTL
levels
,
the
Y
O
loop
and
oset
synthesizer
assembly
is
functioning
correctly
.
If the
levels
are
incorrect,
replace
the
Y
O
loop
and
oset
synthesizer
assembly
.
Note
If this
troubleshooting
procedure
has
determined
that
the
Y
O
loop
and
oset
synthesizer assembly
is
functioning
correctly
but
the
self
test
still
fails
,
the
only
malfunction on
the assembly
is
likely
in
the
self-test
circuitry
on
either
the
Y
O
loop
and
oset
synthesizer
assembly
or
the
microprocessor
assembly
.
Y
ou
can
optionally
isolate
and
replace
either
the
Y
O
loop
and
oset
synthesizer
assembly
or
microprocessor
assembly
to
restore
self
test
functionality
.
Troubleshooting 1-19

Agilent Technologies HP 83711B Specifications

General

Brand	Agilent Technologies
Model	HP 83711B
Category	Test Equipment
Language	English