does anyone know how to get a white line across text like the USA basketball logo?
Draw the shape which is to be knocked out (a line in the example) in a layer above the logo. The colour doesn't matter because it will be made invisible.
Double-click in the space to the right of the layer's name in Layers panel to open its Layer Style window where advanced blending can be modified.
Set Fill Opacity to zero and Knockout to "Deep" or "Shallow" depending on whether the knockout should be limited to a containing Group.