TV Answer Inc of Reston, Virginia has commissioned Hewlett-Packard Co to manufacture an electronic decoder that will attach to a television set and turn it into an interactive system with messages and responses delivered by radio. Users will be able to go home shopping, respond to surveys, pay bills, order home-delivered meals and buy groceries. Television listings and an easy way to program VCRs will also be featured.Hewlett-Packard plans to make over 1.5m of the remote control-activated boxes, to be built around an 8088 with 4Mb of memory and will be about $700. The US Federal Communications Commission has set aside a part of the radio spectrum for such services, and TV Answer expects a licence by year-end. aging receiver that picks up messages from Skytel Corp’s satellite transmission net.