How do i measure an RF Attenuator? Last Updated: 20/08/2014
How to measure an RF Attenuator Using a DSA815-TG Spectrum Analyzer This document provides step-by-step instructions on using the Rigol DSA-800 series of Spectrum Analysers to measure the characteristics of an RF Attenuator.
NOTE: The DSA must have a Tracking Generator to effectively perform the following test.
How to normalize the trace (Optional for accuracy)
Many elements in an RF signal path can have nonlinear characteristics. In many cases, these nonlinear effects on your base measurements can be minimized by normalizing the instrument.
A. Connect tracking generator output to RF input using the same cabling that you will be using to test your device. Any element, like an adapter, used during normalization should also be used during device measurement as any changes to the RF signal path could effect the accuracy of the measurement.
B. Enable the tracking generator by pressing the TG button > TG On
C. Store the reference trace by pressing the TG button > Normalize > Stor Ref
D. Enable normalization by pressing the TG button > Normalize > Normalize On. Also set the Norm Ref Lvl to 0dB as shown below
How to measure the Attenuator
1. Connect the tracking generator output to the filter input using the appropriate cabling and connectors.
2. Connect the filter output to the instrument RF input.
Image showing the TG and RF in of the DSA815-TG spectrum analyser 3. Set the tracking generator amplitude to 0dB by pressing the TG button and the TG Amplitude. You can use the keypad or wheel to enter the correct value.
4. Enable the Tracking generator by pressing the TG button > RF Source ON
5. You can now enable the Marker function to measure the attenuation characteristics of the filter . 6. Press Marker Fctn > N dB BW and set the function to the amplitude of interest. In this example, we are measuring the 3dB Bandwidth of our filter
7. You should now be able to change the dial on the attenuator and test it at each level.