Operation
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© 2017 Pico Technology
pv106ug r1
Impedance conversion for devices that are not 50 Ω
The measurement enhancement window
The
Bandwidth
setting refers to the receiver bandwidth. Maximum sweep speed is achieved with the highest
(140 kHz) setting. On the other hand, the widest dynamic range (lowest noise floor) is achieved with the
lowest value, 10 Hz. Note that the bandwidth setting used during calibration determines the maximum
dynamic range achievable during measurements. So, consider this when carrying out a calibration. For
example, if you need to carry out measurement over more than, say 90 dB dynamic range, then use a 500 Hz
or less bandwidth setting when calibrating.
The
Port 1 Level
sets the test signal level. The default value is +3 dBm as this gives best overall
measurement accuracy. However, it may be necessary, particularly when measuring active devices (e.g.
amplifiers) to reduce the test level. For maximum dynamic range, then use the highest power setting. For
best measurement accuracy it is recommended that the calibration is carried out at the same test level as it
is intended to use for the measurement. Whenever the test level is different to that used for the calibration, a
‘?’ will be added to the calibration status indicator on the Status Panel (Fig. 6.1)
The
Reference Plane
facility allows the reference plane of each parameter measurement to be arbitrarily
moved away from the calibration plane. The value entered applies to the measurement parameter (S
11
, S
21
,
S
12
or S
22
) displayed on the active channel. Note that the same plane value will be used for all other
measurements on that same parameter regardless if they are on the active channel or not.
The
Auto Reference
automatically moves the reference plane. It uses the measurement on the active
channel. This feature is particularly useful, for example, when measuring microstrip devices and it is
necessary to remove the effect of the connecting input and output lines. It takes the effective dielectic
constant value entered to correct the displayed value. Refer to
Reference plane extension and de-embedding
for more details.
Note:
The reference plane must be at 0 mm for the Auto Ref function to work correctly. Also, Enhancement
window changes only take place when the instrument is sweeping.
