U3020AS16
Service Information
1-
Front Panel Input Port LEDs
1.
If the Input Port LEDs do not operate when you have executed a Port
Selection command on the Test Set continue with the following
procedure:
a.
If you have determined that the RF switch is operating, either by an
audible sound or by an RF
S21
port measurement,
remove the top
cover of the instrument.
b.
Ensure that the ribbon cable going from the Controller Module
I/O
port to the front panel LED board
is
properly in place.
c.
Measure the three labeled output power supply voltages on the
Controller Module at the green connector.
d.
If any voltages are not present, the Controller Module Power Supply
will need to be replaced.
e.
If the Power Supply voltage are all present, suspect the front panel
Input Port LED board or the Controller Module I/O section.
RF Switch is
n
ot Switching
1.
If the RF
s
witches are not operating
,
continue with the following
procedure:
a.
Determined if you can hear an audible switching sound.
b.
If an audible sound is heard, but the switch is not being properly
control in order for the correct Port to be selected, it is possible that
the instrument Power On preset set has been corrupted.
c.
for support in
recovering this preset
set.
d.
If no audible sound is heard, remove the top cover of the
instrument.
e.
Insure that the ribbon cable connections at the distribution board
and
switch are properly in place.
f.
Measure the three labeled output power supply voltages on the
Controller Module at the green connector.
g.
Measure the DC-DC Converter input (12 Vdc) and output (24 Vdc).
h.
If any voltages are not present, the Controller Module Power Supply
will need to be replaced.
36
Keysight U3020AS16 User's and Service Guide
