4 Audio Generator Functions98 Keysight U8903A User’s GuideThe variable phase waveform menu is shown as follows.Figure 4-5 Variable phase waveform menuThe variable phase waveform may be configured with the following parameters.– Frequency– Amplitude– Phase → 1Phase → 1 refers to the phase of the selected channel with reference to channel 1.Dual sine waveformThe dual sine waveform group allows you to generate a composite waveform thatis the summation of two independent sine waveforms. Dual sine waveforms areuseful in testing the intermodulation distortion characteristics of an audio system.To select a dual sine waveform, press Waveform > Dual Sine.