U3022
B
H10
High Power Measurements
Selecting REF Attenuator Value
This procedure will select the attenuator value to be installed in the RCVR R1 IN (REF 1) or
RCVR R2 IN (REF 2) paths. The attenuators will be installed from the external coupler ARM and
the REF Inputs.
1. Measure the external coupler ARM power.
2. Add attenuator to ensure the power level does not exceed the optimum REF INPUT level.
Refer to your PNA-X specifications to optimize power levels to the REF ports.
For example:
•
Measured power at the external coupler’s ARM –5 dBm
•
The optimum PNA-X receiver power level
–15 dBm
3. Calculate the amount of attenuation used between the external CPLR ARM and
RCVR R1 IN.
Equation
3 REF IN Attenuation Example
4.
Connect the 10 dB attenuator (calculated from the example) to the external CPLR ARM. If
the power level is less than −15 dB an attenuator is not required.
5.
Measure the attenuator output power.
6.
Verify that the power measured in the previous step is within the acceptable limits (–15
dBm for the RCVR REF IN).
7.
Turn Off the booster amplifier and connect the external coupler ARM to the REF INPUT
(RCVR R1 IN or RCVR R2 IN). Refer to
–15
dB
(
) – –5
dB
(
) = –10
dB
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U3022BH10 User's and Service Guide
