Voices

PBS Expands Online Video Offerings

PBS revamped its online video offering Wednesday, adding full-length episodes from shows such as “Antiques Roadshow” and “Nova,” as it attempts to broaden its audience and sponsorship opportunities. The public broadcaster is aiming for younger viewers who don’t tune in to “Masterpiece Theater” on television, but — it hopes — will be interested in its programming if it’s more accessible on the Web.