In 1930, in an effort to provide cinemas with the means to show live programs, Lee DeForest (the inventor of the audition tube and developer of sound-on-film systems) began a three-year effort to build a hybrid electronic film recorder and projector. The plan was for cinemas to receive the programs on multiple radio frequencies. The recorder/projector would use a conventional 35MM intermittent motion gate and carbon arc lamp. The film would be special blank stock coated with a thin conductive metallic coating. A complex mechanism of spinning needles would cover the frame in a raster-like motion while burning tiny holes in the metallic coating with high-voltage sparks. Although never publicly demonstrated, lab reports claimed it was capable of 75 lines resolution at "near-photographic" quality.