Opt.003 ASTM 2520 Method

The ASTM 2520 is described in “Test methods for complex permittivity (Dielectric Constant) of solid electrical insulating materials at microwave frequencies and temperatures to 1650°, ” ASTM Standard D2520, American Society for Testing and Materials

It is also described in Keysight's Application Note: Basics of Measuring the Dielectric Properties of Materials

An X-band fixture that conforms to ASTM Standard D2520

When Resonant Cavity Methods (Opt. 003) is selected from the Measurement Launcher, the following dialog appears:

Select ASTM 2520.

Cavity / Sample Volume

Click in the numeric field for each of the volumes to start the Volume Calculator dialog.

Select the units for the physical measurements.
Select the geometry of the Cavity / Sample (Round or Rectangular).
Enter dimensions::
- For Round, enter the Height and Diameter.
- For Rectangular, enter the Height, Length, and Width.

Calculate Fc - Calculates the frequencies at which a waveguide with specific dimensions becomes resonant. Learn more about this dialog.

Set (Frequency) Range and other measurement parameters

The dialog box shown below will be displayed when you click Set Range with either the ASTM or Split Post methods selected.

Set the Power level of the measurement.
Set the IFBW and number of points for the measurement. A lower IFBW (bandwidth) improves signal to noise ratio, but also increases the measurement sweep time.
Set the start and stop frequency of the sample measurement. The search frequency range should be set so the resonance of the empty fixture and the fixture with the sample appear as shown below.

Cavity and Sample F and Q

Remove the sample from the cavity, then click Measure to trigger a measurement of the empty cavity’s resonant frequency and Q.

Then replace the sample in the cavity and click Measure.

This range can be setup manually and then read by clicking on the “Read Analyzer” button. Once a measurement is triggered the software will zoom in to the measured resonance as shown.