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Figure 69: Verifying VHF Duplexer Isolation — Connecting Duplexer Cable Assembly
5.10.4.7.1
Verifying VHF Duplexer Isolation
Procedure:
1
Connect test equipment as shown in
Figure 68: Verifying VHF Duplexer Isolation — Connecting
2
Observe and note the level in dBm as shown on the service monitor.
3
Connect the test equipment to the duplexer as shown in
Figure 69: Verifying VHF Duplexer
Isolation — Connecting Duplexer Cable Assembly on page 175
4
Observe and note the level in dBm as shown on the service monitor. (If no number is displayed,
consider isolation to be greater than 105 dB, which exceeds the specification.)
5
Subtract the absolute number noted in step 4 from the number noted in step 2. The difference
should be less than 75 dB to meet specification for isolation.
6
Repeat steps 1 through 5 for Low-Pass/High-Notch cavities with the following exceptions:
a
Set service monitor for Rx or Tx frequency, whichever is higher.
b
Connect service monitor to Low Pass duplexer input (cavity #1).
MN003286A01-E
Chapter 5: GTR 8000 Base Radio Optimization
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