4957D/E/F Microwave Analyzer Quick Start Guide
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The measured power readings are displayed in two ways, dial and number, and the latter
also offers display in dB or uW.
3.5 Measuring the Electrical Length of Cables or Other DUTs in the
VVM Mode
The VVM mode of 4957D/E/F is a very convenient tool to ensure the phase matching of
RF cables. It is mainly used to measure the electrical lengths of cables or other DUTs.
This mode can directly replace a vector voltmeter and has the same flexible and
convenient operation interface as the vector voltmeter. The results of single port electrical
length measurement are displayed in amplitude and phase formats, while the results of
all port are only displayed in the amplitude format.
The test steps are shown as follows:
1. Mode selection
Connect the cable under test or another DUT to the network input port 1 of the analyzer
as shown in Figure 3.9. Press [Mode] after startup and preheating, then select the
VVM
mode with the touch screen, and press [OK] to complete.
Figure 3.9 Measurement connection of the VVM mode
The interface of the VVM mode is shown in the figure:
Figure3.10 Test interface of the VVM mode
Microwave Analyzer
S11
DUT
Device
under test
