Nostalgia Television will test the waters of interactive TV in coming weeks with the introduction of a new gameshow, “The Memory Bank.”While several TV producers have been experimenting with the interactive genre , “The Memory Bank” is believed to be the first full-length program of this type on a cable programming service. Scott Sternberg is producing the trivia gameshow, which allows viewers to play at home through their touchtone phone. Sternberg, a former producer of “The Hollywood Squares” and “The Newlywed Game,” is also the exec producer of another Nostalgia gameshow, “Let’s Go Back” and “Dancin’ to the Oldies.” Viewers will participate by calling a 900-number at the start of the program. They can record their multiple choice answers on the telephone keypad through four rounds of questions. During the rounds, they can withdraw from the game, take winnings or advance to higher levels. The producers will shell out cash and prizes to winners. Nostalgia will debut “Memory Bank” on Nov. 19 at 7 p.m., but it has not yet decided if that timeslot will be its permanent home. Senior VP of programming Frank Jett said the network will test the show on different days and in various dayparts. Still under consideration is whether it should air once a week or as a strip. It is noteworthy that a cable web aimed at older audiences will be the first to try out this new technology. Jett rejects the notion that the 45-plus crowd is not a likely target to embrace an interactive program.