Troubleshooting
6.
Measure the
voltage at
TP4 on
the YIG
Driver assembly
.The
voltage should
be
within
the
tolerance
shown in
the table
.If
it is
missing or
isn't within
tolerance,
replace
the
YIG
Driver
assembly
.If
it is
within tolerance
, check
the continuity
of the
ABUS cable
(W9)
with
an
ohmmeter
and
replace
it if
necessary.
7.
Use
the
direct control
function to
cause the
analog multiplexer
on the
YIG Driver
assembly
to
switch the
\no connect"
input to
its output.
a.
Press
4
SPCL
5
.
b.
Press
4
60
5
on
the
numeric keypad,
then terminate
the entry
by
pressing
4
Hz
5
(ENTER).
c.
Press
4
48
5
on
the
numeric keypad,
then terminate
the entry
by
pressing
4
Hz
5
(ENTER).
d.
Press
4
0
5
on
the
numeric keypad,
then terminate
the entry
by
pressing
4
Hz
5
(ENTER).
8.
Measure the
voltage at
TP4 while
disconnecting
the
ABUS
cable
from
each
of
the
other
assemblies
(one at
a time).
The voltage
will
change
to
a
non-negative
value
when
the
ABUS
cable
is removed
from the
assembly that
is
loading
the
ABUS
down.
Replace
the
assembly
that
is loading
the ABUS
down. If
no
change
is
noted
after
the
ABUS
cable
has
been
disconnected
from all
assemblies,
replace the
ABUS
cable
.
Low/High
Band
V
oltage
Errors
Error Group Description
19
=4
YIG
Driver Low
Band
voltage
check
19
=
20
YIG
Driver
High Band
voltage check
1.
Install
the
YIG
Driver
assembly
in
the
service
position.
Refer
to
the
procedure
\YIG
Driver
Board
Assembly
A9"
in
Chapter
5
of
this
manual.
2.
Set
the
synthesizer
output
frequency
to
the
frequency
shown
in
the
following
table
for
the
pertinent
error
reported.
Error
Message
Number
Output
Frequency
D
A
C
Output
V
oltage
(max/min)
19
=
4
4
GHz
0.314
V/0.237
V
19
=
20
12
GHz
0.915
V/0.766
V
3.
Use
the
direct
control
function
to
disconnect
the
oset
voltage
from
the D
AC.
a.
Press
4
SPCL
5
.
b.
Press
4
60
5
on
the
numeric
keypad,
then
terminate
the
entry
by
pressing
4
Hz
5
(ENTER).
c. Enter the oset disconnect address by typing
4
57
5
on the numeric keypad, then terminate
the entry by pressing
4
Hz
5
(ENTER).
d. Enter the oset disconnect value by typing
4
96
5
on the numeric keypad, then terminate
the entry by pressing
4
Hz
5
(ENTER).
4. Measure the
voltage at TP6 on the microprocessor assembly (A3) with a voltmeter (connect
the voltmeter ground lead
to A3TP4). If the voltage is between 0 to 5 volts
, continue with
the next step
.If
the voltage is a negative voltage
, continue with step 8.
5. Use the direct control function to cause the analog multiplexer (U22) to switch the SENSE
line to its output.
a. Press
4
SPCL
5
.
b. Press
4
60
5
on the numeric keypad, then terminate the entry by pressing
4
Hz
5
(ENTER).
c. Press
4
48
5
on the numeric keypad, then terminate the entry by pressing
4
Hz
5
(ENTER).
d. Press
4
1
5
on the numeric keypad, then terminate the entry by pressing
4
Hz
5
(ENTER).
Troubleshooting 1-23
To Next Page
Loading...
Need help?
General
