The Federal Communications Commission has voted to permit cable companies to encrypt television signals to prevent theft by consumers. Encrypting basic cable signals, a practice banned before the FCC ruling last Friday, may require consumers without cable boxes to acquire them. The FCC said the change would “adversely affect a small number of cable subscribers” with TV sets that are directly hooked up to cable connections, as opposed to being controlled remotely through boxes. According to the agency, cable operators and consumers will benefit, on the whole, as the decision will greatly reduce the need for cable providers to dispatch employees to households to disconnect illegal cable service.