From the List <<Positions>> Choose Parasternal Short PA (Left parasternal View, Short axis of the heart at the level of Pulmonary artery) or find the same position with 3D Transducer.
Click Button <<Calculations>> Click Tab <<PA St >> Click Radio Button <<C>>
Click the button <<CW>> to move to Continuous Wave Spectral Doppler (CW).
Place Control Volume between the leaflets of the Pulmonary Valve and click.