Agilent Technologies N5241A, Руководство по обслуживанию

Страница: 118 / 354

4-38 Service Guide N5242-90001
Troubleshooting PNA Series Microwave Network Analyzers
Measurement System Troubleshooting N5241A/42A
WARNING Procedures described in this document are performed with power
supplied to the product while protective covers are removed. Energy
available at many points may, if contacted, result in personal injury.
4. With the covers off, plug in the analyzer and turn on the power.
CAUTION Do not operate the analyzer with the outer cover removed for more than
30 minutes, as this could cause the analyzer to overheat which could result in
costly damage.
Checking the A23 and A24 Mixer Brick Receiver Outputs
Set the network analyzer for an S11 measurement with a CW frequency of 1 GHz.
1. Locate the following flexible cables at the receiver IF outputs of the mixer brick(s).
• 2-port models
— Receiver A; W51 of A23
— Receiver R1; W52 of A23
— Receiver R2; W53 of A23
— Receiver B; W54 of A23
• 4-port models
— Receiver A; W51 of A23
— Receiver R1; W52 of A23
— Receiver R2; W53 of A23
— Receiver B; W54 of A23
— Receiver C; W55 of A24
— Receiver R3; W56 of A24
— Receiver R4; W57 of A24
— Receiver D; W58 of A24
2. Disconnect the flexible cable at the suspect receiver.
3. Connect the spectrum analyzer to the suspect receiver connector.
4. The measured signal on the spectrum analyzer should be at 7.61 MHz.
• If the measured signal is present, continue testing at “Checking the A20 IF
Multiplexer Board” on page 4-39 .
5. If the measured signal is missing on the R1 receiver, continue testing at “Checking the
A33 Reference Mixer Switch” on page 4-39 .
If the measured signal is missing on any receiver (other than the R1 receiver noted
above) and the analyzer does not have receiver attenuators, replace the A23 or A24
mixer brick, whichever is appropriate. Refer to
“Removing and Replacing the A23 and
A24 Mixer Bricks” on page 7-34 .