The MSA as a
Component Meter

Updated Dec 16, 2009
The Function of Component Meter provides a simple way to measure resitors, capacitors and inductors, much like an RLC meter.

Test Results of Component Measurement with the MSA, 10/24/09. a PDF file by Sam Wetterlin.
Analysis of Components with the MSA, 11/6/09. a PDF file by Sam Wetterlin.

 The steps in using this feature are:
1.     Set the video filter to Narrow (large capacitor). (Both the hardware video filter switch and the software Video Filter combobox must be set.)
2.     Open the Measure Components Dialog. You do not have to perform any scan or make any particular settings, other than the video.
3.     Select the type of fixture the DUT is to be mounted in, Series or Shunt.
4.     Enter the impedance (R0) of the fixture, generally 50 ohms.
5.     Select the component type.
6.     For the Series Fixture attach a Short—i.e. a direct, low impedance connection between the terminals of the fixture. A brass strip is frequently a good choice. For the Shunt Fixture, calibration is done with an Open, which in this case means simply attaching nothing to the fixture.
7.     Click Calibrate. The MSA will perform a very quick calibration at 9 frequencies from 100 kHz to 40 MHz.
8.     Remove the Short (if attached) and attach the DUT. Click Measure. The MSA will repeatedly measure the component and update the display. During the measuring process, the label of the Measure button changes to Stop.
9.     Remove the component and attach other components, as desired.
10. When done, click Stop. Measurement will stop at the end of the current 9-point sweep.
11. If desired, click the –Freq or +Freq buttons to show the measurement at other frequencies.
12.  When finished, click Done.
Measurements are made at 9 frequencies, and the MSA chooses to display the one that seems to be at the best frequency for that value component. It is possible for the measurement frequency to be as low as 100 kHz. At such low frequencies, there may be components in the TG signal near the first IF frequency of the MSA that can distort measurements. Therefore, it is a good idea to place a low pass filter on the TG output or the MSA input. The highest measurement frequency is 40 MHz, so the filter should have a corner frequency anywhere from 50 MHz to 900 MHz, and should attenuate signals in the 1000-1100 MHz range by at least 30 dB.
Below is an image of the Component Measurement dialog, measuring a 2006 pF capacitor (per AADE meter).




Measurement accuracy seems to be 2% or better--frequently better than 1%--over a broad range. For a fairly crude Series Fixture, which should be best for higher impedances, that range is about 5 ohms to 100 kohms; for capacitors, 20 pF to 0.1 uF, and for inductors 150 nH to at least 1 mH. A more precise shunt fixture, which 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 components if the accuracy standard is loosened to 10%. Smaller components can also be measured much more accurately if they are soldered directly onto the test fixture, rather than attached to a connector.


Very large inductors with ferrite or iron cores may not be measured accurately if their losses are too high at the measurement frequency. Furthermore, such inductors may have parasitic capacitance high enough to create a self-resonant frequency low enough to interfere with measurement. One such inductor actually had a resonant frequency lower than 100 kHz, the lowest measurement frequency, and therefore appeared to the MSA to be a capacitor rather than an inductor.


Inductors with large losses, or any components whose self-resonant frequency interferes with measurement, are better handled by the RLC analysis available in Reflection mode.