U3022AH10
Troubleshooting the Test Set
3.
Using the Multiport Mode (Option 551), verify the PNA firmware is correct and the Test Set file is
loaded into the PNA. Refer to
"Network Analyzer Requirements" on page
4.
Using the I/O Command values, confirm that the correct address and data values are being
used. Refer to
the address and data value tables on page
5.
6.
Front Panel R and S Indicator LED Check.
a.
Check that the Test Set controller board "Controller Status LEDs" are ON. Refer to
. If the LEDs are OFF, remove the switch driver board and see if the LEDs come on. If the
LEDs are still OFF, replace the controller board.
b.
If the status LEDs are ON and the front panel Active LED is ON, suspect the Front Panel LED
board or the ribbon cable and replace as needed.
7.
Check the DC +21 Vdc switch drive voltages on the switch driver board by connecting a voltmeter to
one of the Jxx locations as shown in
. Do not disconnect the RF switch connector in order
to keep the switch in place as a load for the following voltage measurement.
a.
Measure Pin 3 to Tp1 = +21 Vdc voltages. If +21 Vdc is abnormal, suspect the switch driver
board.
b.
If the +21 Vdc is okay, measure the switch drive line voltage. You should measure > -21 Vdc.
c.
If the voltages are not normal, suspect a faulty RF switch.
Source and Receiver Path Test
If you suspect an RF signal path problem within the Test Set, the following procedure is
provided to check all RF signal paths through the Test Set.
Before beginning this procedure, you should complete the following steps:
•
Install the Test Set I/O interface cable between the PNA and the Test Set on the rear panel.
•
Remove the front panel RF interface cables and reinstall the PNA front panel U-shaped cables.
•
You will need two
26.5
GHz
3.5
mm RF Flex cables and a
3.5
mm f/f adapter.
Equipment Setup
•
Power ON both the Test Set and the PNA-X.
•
Preset the PNA-X, setting the PNA-X to Standalone Mode.
•
Confirm the frequency range is set to 10 MHz to 26.5 GHz.
•
Connect RF Flex cables to PNA Ports 1 and 2. Connect the cables together with a 3.5 mm
adapter.
•
Configure the PNA-X to measure S21 and normalize the response trace.
•
Set the PNA to Interface Control Mode with front panel keys:
Trace/Chan > Channel > Hardware Setup > Interface Control -OR-
(Instrument > Setup > Internal Hardware > Interface Control...)
. In the drop-down window,
select the Enable Interface Control box.
U3022AH10 User's and Service Guide
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