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If
Hardware
Error
Messages
(7000{7999)
Occur
7078
Tune
+
Span
This
hardware
error
occurs
when
the
voltage
at
A10U17
pin
11
(A10
power
supply/driver
)
drops
below
+2.48
V
.
When
this
occurs
,
A10U11
pin
13
goes
to
a
positive
rail
of
about
+11
V
.
This
is
sent
to
the
A12
controller
where
the
error
condition
is
reported.
T
o
solve
this
problem:
1.
V
erify
that
the
Tune
+
Span
signal
is
actually
getting
to
the
RF
section.
2.
If
correct,
check
the
output
of
A10U17
pin
13.
3.
If
the
output
is
a
negative
voltage
,
there
is
a
problem
on
the
A12
controller .
(Refer
to
\Troubleshooting
the
A12
Controller ".)
4.
If
it
is
not
a
negative
voltage
,
troubleshoot
the
A10
power
supply/driver
.
(Refer
to
\Troubleshooting
the
A10
P
ower
Supply/Driver
".)
4-8
T
roubleshooting
Summary of Contents for 70908A
Page 7: ...Servicing at a Glance vi ...
Page 19: ......
Page 44: ...Figure 2 1 Main Menu Softkeys Module Veri cation Software 2 19 ...
Page 45: ...Figure 2 2 Mass Storage Menu and Parameter Menu Softkeys 2 20 Module Veri cation Software ...
Page 47: ...Figure 2 4 Test Menu Softkeys 2 22 Module Veri cation Software ...
Page 55: ......
Page 61: ......
Page 94: ...Troubleshooting the A3 SYTFMD Figure 4 5 Discriminator Output Waveform Troubleshooting 4 33 ...
Page 125: ......
Page 139: ......
Page 205: ......
Page 209: ...Test 01 Flatness Figure 8 2 Equipment Setup for Test 01 Flatness 8 4 Module Veri cation Tests ...
Page 267: ......
Page 271: ...Front Panel Figure 9 2 Front Panel Removal Replacement 1 of 2 9 4 Replacing Major Assemblies ...
Page 272: ...Front Panel Figure 9 3 Front Panel Removal Replacement 2 of 2 Replacing Major Assemblies 9 5 ...
Page 274: ...Rear Panel Figure 9 4 Rear Panel Removal Replacement 1 or 2 Replacing Major Assemblies 9 7 ...
Page 275: ...Rear Panel Figure 9 5 Rear Panel Removal Replacement 2 or 2 9 8 Replacing Major Assemblies ...
Page 284: ...A3 SYTFMD Figure 9 10 A3 SYTFMD Removal Replacement Replacing Major Assemblies 9 17 ...
Page 294: ...A7 2nd Mixer Figure 9 17 A7 2nd Mixer Removal Replacement Replacing Major Assemblies 9 27 ...
Page 329: ......