PicoVNA 106 6 GHz Vector Network Analyzer
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© 2017 Pico Technology
pv106ug r1
The
Effective Dielectric
of the device under test can be entered so that the displayed Reference Plane
extension values (shown on the Enhancement Window) are corrected accordingly when the Auto Ref button
is clicked. The default value is 1.0 and the maximum value allowed is 50.0.
Note:
The reference plane extension value shown in the
main window
on the markers display panel on the
right is the reference plane extension as shown in the Enhancement window.
The
de-embedding
facility is explained in detail in
Reference plane extension and de-embedding
.
The
System Z
0
Conversion
facility allows measurements, which are always taken in 50 Ω, to be converted to
another impedance selected by the user. This feature can be useful, for example, for measuring 75 Ω
devices. The value of Z
0
entered must be real (purely resistive) and must be within the range of 10 Ω to 200
Ω. Whenever this facility is selected, an indicator is displayed on the top right corner of the graphics display
as shown in the second figure below.
Note
that when requested, impedance conversion will performed on
the
live measurement
and any stored
memory trace
.
There are two possible ways of using the
System Z
0
Conversion
facility. For example, 75 Ω devices can be
measured using the techniques illustrated below.
Possible techniques for measuring 75 Ω devices.
Impedance matching pads can be used to measure a connectorized device.
A discrete device mounted on a 50 Ω test jig is somewhat simpler to measure.
The steps necessary for each of the two techniques illustrated in the figure above are as follows:
75 Ω device with connectors
i.
Connect
50 Ω to 75 Ω impedance matching networks
(e.g. matching pads) at the ends of the cables
connected to ports 1 and 2.
ii. In the
Enhancement
window, check the
Convert System Zo
box
iii. Check
External Zo match
to indicate external matching networks in use
iv. Enter
75
in the
Convert System Zo
value box and click
Apply
v. Proceed to calibrate using a
75 Ω calibration kit
vi. Connect the DUT and
start the measurement
75 Ω device mounted on 50 Ω test jig
i.
In the
Enhancement
window, uncheck the
Convert System Zo
box
ii. Calibrate at the ends of the test cables using a 50 Ω calibration kit
iii. Apply de-embedding to remove test jig effects. See
Calibration kit
for some suggestions.
iv. In the
Enhancement
window, check the
Convert System Zo
box
