Performing (and Calibrating) a Basic Return Loss Measurement

Performing (and Calibrating) a Basic Return Loss Measurement
Select the desired frequency range and calibrate the test set (using calibrated Open, Short, and Load connectors) for a return loss measurement.

Step
Notes

1
Mode

2
[Antenna/Cable]

3
[Return Loss]
The return loss measurement takes a few seconds to load.

4
[Start Freq]

5
Enter the start frequency using the numeric keypad.

6
[Hz], [kHz], [MHz], or [GHz]

7
[Stop Freq]

8
Enter the stop frequency using the keypad.
The stop frequency should be larger than the start frequency.

9
[Hz], [kHz], [MHz], or [GHz]

10
Check whether your analyzer has already been calibrated over the frequency range that you wish to measure. If it is already calibrated over the correct frequency range, you can omit the next step (Step 11) and go straight to Step 12.
The analyzer displays its calibration status on the top left of the measurement screen. You only need to re calibrate if you:
power off the test set
change the start frequency to a new value that lies below the start frequency of your previous calibration
change the stop frequency to a new value that lies above the stop frequency of your previous calibration
change any of the jumper leads that you used for the calibration
change any of the attenuators that you used for the calibration
change the type of cable specified under the [Cable Type] menu key in the Distance to Fault measurement.
For more information, see "Calibration - Minimizing your Workload"

11
If your analyzer is uncalibrated, or has been calibrated over an unsuitable frequency, press [Calibrate]
Follow the instructions of the Calibration Wizard. The test set will calibrate over the desired frequency range.

12
Connect the antenna feedline and antenna.
Connect the antenna feedline cable to the RFout/SWR port.

13
[Level]
Below the Return Loss display is a table displaying the Frequency, the Return Loss, and the Standing Wave Ratio (SWR) of the best and worst return losses. These values may be changing rapidly. To isolate a signal, use a single sweep, or apply averaging to the trace data.

If the Return Loss trace is not visible, you can change the reference level, or use Autoscale to have the test set select a reference level for you.

To choose Autoscale, press [Autoscale].
To set the reference level manually, press [Ref Level], enter a value using the numeric keypad, then press [dB].

NOTE: If the Return Loss measurement looks suspect (less than 5 dB), you may want to perform a Distance to Fault measurement to determine if a noticeable fault exists and where it may be located. For more information see "Distance to Fault"


	Step	Notes
1	Mode
2	[Antenna/Cable]
3	[Return Loss]	The return loss measurement takes a few seconds to load.
4	[Start Freq]
5	Enter the start frequency using the numeric keypad.
6	[Hz], [kHz], [MHz], or [GHz]
7	[Stop Freq]
8	Enter the stop frequency using the keypad.	The stop frequency should be larger than the start frequency.
9	[Hz], [kHz], [MHz], or [GHz]
10	Check whether your analyzer has already been calibrated over the frequency range that you wish to measure. If it is already calibrated over the correct frequency range, you can omit the next step (Step 11) and go straight to Step 12.	The analyzer displays its calibration status on the top left of the measurement screen. You only need to re calibrate if you: power off the test set change the start frequency to a new value that lies below the start frequency of your previous calibration change the stop frequency to a new value that lies above the stop frequency of your previous calibration change any of the jumper leads that you used for the calibration change any of the attenuators that you used for the calibration change the type of cable specified under the [Cable Type] menu key in the Distance to Fault measurement. For more information, see "Calibration - Minimizing your Workload"
11	If your analyzer is uncalibrated, or has been calibrated over an unsuitable frequency, press [Calibrate]	Follow the instructions of the Calibration Wizard. The test set will calibrate over the desired frequency range.
12	Connect the antenna feedline and antenna.	Connect the antenna feedline cable to the RFout/SWR port.
13	[Level]	Below the Return Loss display is a table displaying the Frequency, the Return Loss, and the Standing Wave Ratio (SWR) of the best and worst return losses. These values may be changing rapidly. To isolate a signal, use a single sweep, or apply averaging to the trace data. If the Return Loss trace is not visible, you can change the reference level, or use Autoscale to have the test set select a reference level for you. To choose Autoscale, press [Autoscale]. To set the reference level manually, press [Ref Level], enter a value using the numeric keypad, then press [dB].