4613_WLS

Page 671 of the Fall issue of the Sears Roebuck catalog lists this tube as a "Multivalve" tube and it was made by the Emerson Radval Corp, 25 West 43rd St, New York. The type number of the tube is EM3VA. This company had very close ties with the Cleartron Vacuum Tube Co of 28, 44th St, New York and it is understood that they had interconnecting doors (or a yard) at the rear of each building). According to Tynes' "Saga of the vacuum Tube", Emerson literature for this tube was printed by Cleartron. As was typical with Cleartron tubes, the tip of the "Multivalve" has been flattened at the top, during manufacture.The tube is a triple triode with the second and third plate and grid connections from two sets of binding posts mounted on a bakelite disc attached to the top of the UX base. The tube is also listed in the Spring 1929 catalog.