Check the Calibration
A good first check of the calibration is to measure the
transmission and reflection characteristics of the longer air
line. Connect the air line between Port 1 and Port 2 and
view the
magnitude and phase and the
magnitude.
The air line should exhibit low insertion loss and linear
phase. The
should be constant over the entire
frequency range.
2-7 Line with Short Circuit
2-7 Line Magnitude and Phase
For a second check, connect the 2-7 Line to Port 1, then
connect the Short circuit to the end of the air line, and view
the reflection response.
Select:
S
D
O M A I N
TIME BAND PASS
View the
response. Use the marker to measure the
responses at 0 seconds (a rough measure of effective
directivity) and the mismatch at twice the length of the air
line (a rough measure of effective source match). The trace
should appear as shown below. If not, the calibration has
not been performed correctly or the calibration devices are
defective.
Plot of Time Band Pass with Shorted Air Line
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