Technical Notes

Frequency Response Measurements

The Frequency Response or Analog Network Analyzer can measure Magnitude and Phase which allows measurements for the following applications:

  • Filter characterization including Insertion loss, passband and stopband frequencies
  • Component characterization including impedance and resonant frequencies
  • Bode style plots for loop gain/feedback stability analysis of amplifiers, power supplies and control systems
  • Bandwidth of input and output stages

Graph of the Frequency Response of a 10.7 MHz Bandpass Filter

Graph: Frequency Response

Basic Setup:

Basic Setup

The analyzer has two input channels for ratioed, transfer function measurements.

To obtain a circuit's transfer function, the analyzer's source and channel A are connected to the circuit's input node while channel B is connected to the circuit's output node.

The source signal, which provides the stimulus for the circuit under test, can be injected into the circuit either directly or AC coupled using a transformer. The frequency sweeps can be either logarithmic (for Bode type plots) or linear.