Agilent Technologies HP 83711B Service Guide

Troubleshooting
2. Use
the direct
control function
to set
the suspected
failing bit
of
the
D
A
C
(U8)
on
the
YIG
Driver assembly
(A9) high
while setting
all other
DA
C bits
low
.
Direct
control
addresses
are
shown in
the following
table.
Bit
P
osition
Oset
Disconnect
A
ddress
Oset
Disconnect
V
alue
D
A
C
A
ddress
D
A
C
V
alue
256 57 96 49 256
512 57 96 49 512
1024 57 96 49 1024
2048 57 96 49 2048
4096 57 96 49 4096
8192 57 96 49 8192
For
example,
to
set
the
512
bit
position
on
the
D
A
C
high
while
setting
all
other
bits
low:
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
oset
disconnect
address
by
typing
4
57
5
on
the
numeric
keypad,
then
terminate
the
entry
by
pressing
4
Hz
5
(ENTER).
d.
Enter
the
oset
disconnect value
by typing
4
96
5
on
the
numeric
keypad, then
terminate
the
entry
by
pressing
4
Hz
5
(ENTER).
e.
Press
4
SPCL
5
.
f. Press
4
60
5 on
the
numeric
keypad,
then
terminate
the
entry
by
pressing
4
Hz
5 (ENTER).
g. Enter
the
D
A
C
address
by
typing
4
49
5 on
the
numeric
keypad,
then
terminate
the
entry
by
pressing 4
Hz
5 (ENTER).
h.
Enter the
D
A
C
value
by
typing
4
512
5
on the
numeric
keypad,
then
terminate
the
entry
by
pressing
4
Hz
5
(ENTER).
3.
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
7.
4.
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).
5. Measure the voltage at TP6 on the microprocessor assembly
. If the
voltage is within the
tolerance shown in the following table
, replace the microprocessor assembly
.Ifit
is missing
or out of tolerance
, continue with the next step
.
Bit
Position
MUX Output V
oltage
(max/min)
256 0.12 V/ 0 0.07 V
512 0.168 V/0 V
1024 0.24 V/0.048 V
2048 0.336 V/0.12 V
4096 0.673 V/0.288 V
8192 1.202 V/0.841 V
1-22 Troubleshooting

Agilent Technologies HP 83711B Specifications

General

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