Local and national officials of the National Assn. of Broadcast Employees and Technicians on Monday protested a reported weekend poll by members in New York, Chicago and Washington to determine if the union's full membership should vote on a disputed NBC contract proposal. Officials worried that the poll's results could undermine the union's bargaining position. Carrie Biggs-Adams, president of the union's Local 53 in Burbank, said she didn't expect the union's overall strategy to be affected. Union negotiators will discuss the matter Wednesday. The strike, longest in the union's history, began June 29.