Technical data

4-34 Service Guide N5230-90025
Troubleshooting PNA Series Microwave Network Analyzers
Measurement System Troubleshooting N5230C
Checking the A6 Multiplier Output, All Bands
Perform this procedure if you observe a problem in all bands in all receivers.
1. Refer to the block diagram at the end of this chapter and to “Top Cables, All Options Except 146/246” on
page 6-14. Locate the flexible cable W3, at the A6 multiplier board.
2. Disconnect W2 from the A6 board.
3. Connect the spectrum analyzer to the open connector.
4. Set the network analyzer for a 2 GHz CW frequency and observe the spectrum analyzer measurement.
• The spectrum analyzer should measure a signal at 2 GHz (plus the 7.66 MHz offset).
5. If the signal is not present and the signals are present from “Checking the A7 Fractional-N Synthesizer
Output, Bands 5 through 17,” replace the A6 multiplier board. Refer to “Removing and Replacing the A5
through A10 Boards” on page 7-16.
6. If the signal is present, reconnect cable W3, and then continue with “Checking the A9 Fractional-N
Synthesizer Output, Bands 0 through 3” on page 4-34.
Checking the A9 Fractional-N Synthesizer Output, Bands 0 through 3
Perform this procedure if you observe a problem in bands 0 through 3 in all receivers, or in the A and B
receivers for Options 146 and 246.
1. Refer to the block diagram at the end of this chapter and to “Top Cables, All Options Except 146/246” on
page 6-14. Locate the flexible cable W5, at the A9 fractional-N synthesizer board.
2. Disconnect W5 from A9J101.
3. Connect the spectrum analyzer to A9J101.
4. Set the network analyzer for a 500 MHz CW frequency and observe the spectrum analyzer measurement.
• The spectrum analyzer should measure a signal at 507.66 MHz.
5. If the signal is not present and the 5 MHz reference signal is present from “Checking the A10 5 MHz
Reference Output, All Bands,” replace the A9 fractional-N synthesizer board. Refer to “Removing and
Replacing the A5 through A10 Boards” on page 7-16.
6. If the signal is present, reconnect cable W5, and then continue with “Checking the A9 Fractional-N
Synthesizer Output, Band 4” on page 4-34.
Checking the A9 Fractional-N Synthesizer Output, Band 4
Perform this procedure if you observe a problem in band 4 in all receivers, or in the A and B receivers for
Options 146 and 246.
1. Refer to the block diagram at the back of this chapter and to “Top Cables, All Options Except 146/246” on
page 6-14. Locate semirigid cable W4, at the A9 fractional-N synthesizer board.