Privately-owned Nottingham cable telephone and television services company Diamond Cable Plc has ordered three more System X exchanges from GEC Plessey Telecommunications Ltd as part of a new UKP230m five-year programme to expand coverage of its franchises in central and eastern England: the investment will create 200 jobs in 1994; Diamond has seven franchises in all, which operate 10,000 telephone lines and reach 32,000 homes with cable television, and they cover Grimsby, Grantham, Newark, Melton Mowbray, Mansfield, Lincoln and Nottingham; Diamond also plans to offer pay-per-view videos and interactive games later this year, and banking and education packages.