NBC president stepping down

NBC president Fred Silverman, whose three-year battle to boost ratings failed to lift the network from its No. 3 position, resigned, saying he had failed to get support from the new head of RCA, NBC's parent company.

A spokesman said RCA would issue a statement "on NBC management" later. A network source said Grant Tinker, former husband of Mary Tyler M oore and head of MTM Productions, would replace Silverman.