the video filter to Narrow (large
the hardware video filter switch and the software Video Filter combobox must be set.)
the Measure Components
Dialog. You do not have to perform any scan or make any particular
other than the video.
the type of fixture
the DUT is to be mounted in, Series or Shunt.
the impedance (R0) of
the fixture, generally 50 ohms.
the component type.
the Series Fixture
attach a Short—i.e. a direct, low impedance connection between the
the fixture. A brass strip is frequently a good choice. For the Shunt
calibration is done with an Open, which in this case means simply
nothing to the fixture.
Calibrate. The MSA
will perform a very quick calibration at 9 frequencies from 100 kHz to
the Short (if
attached) and attach the DUT. Click Measure. The MSA will repeatedly
the component and update the display. During the measuring process, the
of the Measure button changes to Stop.
the component and
attach other components, as desired.
done, click Stop.
Measurement will stop at the end of the current 9-point sweep.
desired, click the –Freq
or +Freq buttons to show the measurement at other frequencies.
12.When finished, click Done.
are made at 9 frequencies, and the MSA chooses to display the one that
be at the best frequency for that value component. It is possible for
measurement frequency to be as low as 100 kHz. At such low frequencies,
may be components in the TG signal near the first IF frequency of the
can distort measurements. Therefore, it is a good idea to place a low
filter on the TG output or the MSA input. The highest measurement
40 MHz, so the filter should have a corner frequency anywhere from 50
900 MHz, and should attenuate signals in the 1000-1100 MHz range by at
is an image of the Component Measurement dialog, measuring a 2006 pF capacitor (per AADE meter).
accuracy seems to be 2% or better--frequently better than 1%--over a
range. For a fairly crude Series Fixture, which should be best for
impedances, that range is about 5 ohms to 100 kohms;
for capacitors, 20 pF to 0.1 uF,
and for inductors 150 nH
least 1 mH. A more precise shunt fixture,
should be better for low impedances, had a range for resistors from 3
ohms to 1
kohm (and was respectable below 1 ohm); for
capacitors, 15 pF to 1 uF;
and for inductors 100 nH to at least 1 mH. Both fixtures could measure much smaller
the accuracy standard is loosened to 10%. Smaller components can also
measured much more accurately if they are soldered directly onto the
fixture, rather than attached to a connector.
large inductors with ferrite or iron cores may not be measured
their losses are too high at the measurement frequency. Furthermore,
inductors may have parasitic capacitance high enough to create a
frequency low enough to interfere with measurement. One such inductor
had a resonant frequency lower than 100 kHz, the lowest measurement
and therefore appeared to the MSA to be a capacitor rather than an
with large losses, or any components whose self-resonant frequency
with measurement, are better handled by the RLC analysis available in