RCA used Valensi's concept as the basis of all of its developments, believing it to be the only proper solution to the broadcast problem. However, RCA's early sets using mirrors and other projection systems all suffered from image and color quality problems, and were easily bested by CBS's hybrid system. But solutions to these problems were in the pipeline, and RCA in particular was investing massive sums (later estimated at $100 million) to develop a usable dot-sequential tube. RCA was beaten to the punch by the Geer tube, which used three B&W tubes aimed at different faces of colored pyramids to produce a color image. All-electronic systems included the Chromatron, Penetron and beam-index tube that were being developed by various companies. While investigating all of these, RCA's teams quickly started focusing on the shadow mask system.