MAtched
Adapters
With this method, you use two precision matched adapters which are “equal.
n
lb be equal,
the adapters must have the same match,
ZO,
insertion loss, and electrical delay. The adapters
in most HP calibration kits have matched electrical length, even if the physical lengths appear
different.
NON-INSERTABLE DEWCE
1.
TRANSMISSIOf4
CAL USING
ADAPTER A
2 REFLECTION CAL USING
ADAPTEP
R
LENGTH OF
ADAPTERS MUST BE
EQJAl
3. MEASURE
DUT
USING
ADAPTER
6.
pg6136d
Figure 5-15. Calibrating for Noninsertable Devices
‘Ib
use this method, refer to Figure 5-15 and perform the following steps:
1. Perform a transmission calibration using the first adapter.
2. Remove adapter A, and place adapter B on port 2. Adapter B becomes the effective test
port.
3. Perform a reflection calibration.
4. Measure the test device with adapter B in place.
The errors remaining after calibration with this method are equal to the differences between
the two adapters that are used.
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Optimizing Measurement Results