Deaf Mosaic 310.  National Theatre of the Deaf 20th Anniversary season, including excerpts from "The Dybbuk" and interviews with performers Andy Vasnick, Perry Lee, Elena Blue and Sandi Inches, along with NTD founder David Hays; wildlife painter Louis Frisino; "Sound and Silence," a model exhibit on deafness at the Capitol Children's Museum; marathon runner Flo Vold on her preparations for a big race; Alice Cogswell, the first deaf student in America, is profiled by "Deaf Portrait."  [January, 1988]