Chapter 11 2-Port Phase Testing
98
CellAdvisor JD720C User's Manual
requires you to perform a new calibration.
4
To set the number of measurements to be averaged, complete the following steps:
a
Select the input box next to the
Average
.
b
Enter a value between one and five.
5
To enable the
Interference Rejection
feature, select
On
.
NOTE
Default setting is
Off
. It is recommended to use this feature only when you suspect
interfering signals in the area as it slows down measurement.
6
For JD725C and JD726C users with the option 001 Bias Tee installed.
To use the Bias Tee,
complete the following steps:
a
Select
On
for the
Bias Tee
.
b
Enter a value between
12
and
32
with 1 V step, as you desire.
NOTE
If you have set this Bias Tee to
On
, the instrument will supply a DC bias of set level
(12
– 32 V) from the
RF In
port to an active device, such as Tower Mounted Amplifier
(TMA) or Low Noise Amplifier (LNA), through the transmission line, eliminating the
need of an external power supply.
7
Tap the
Apply
button in the lower-right corner of the setup screen to save the change(s).
Performing calibration
Perform the O-S-L-Thru Calibration by pressing the
CAL
hard key. The instrument displays
on-screen instructions for you to follow through. See
“Performing 2-port calibration” on page
40 for more information.
Making a measurement
Once the calibration is done, the instrument is now ready to make a measurement.
Procedure
1
Disconnect the calibrated extension cable from the
RF In
port of the instrument.
2
Connect your DUT between the extension cable and the
RF In
3
Your measurement result is displayed on the screen in real time.
