Agilent Technologies 8719ET Service Manual page 233

8719ET/20ET/22ET
8719ES/20ES/22ES
RF Network Analyzers
2. The following components may be at fault. Refer to the overall block diagram at the end
of Chapter 4 for information.
A25 (switch)
3. Since the analyzer phase locked in low and/or mid band, all of the phase lock circuitry is
working, so look for low power as a cause of phase lock errors.
4. Check power at the output of A25 switch at J3.
• If the power is less than +5 dBm, check the insertion loss of A25 switch and the
associated cabling.
• If the power out of the A25 switch is greater than +5 dBm, the problem is probably
above 24 GHz. Proceed with the next steps.
5. Check all RF cabling and connections.
• If any of the cables or connectors are bad, have them repaired or replaced.
• If the cables and connectors are good, replace the A54 YIG 2. If high band problems
still persist, then replace the A58 M/A/D/S.
Service Guide
A6 (source switch) A58 M/A/D/S A54 YIG 2
Source Troubleshooting
Band-Related Problems
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