Like most cable TV networks around the world, Wharf relies on a combination of mediums, including optical fibre, copper wire and microwave signals. Out of the 1.5 million Hong Kong homes that Wharf said could potentially receive cable television, more than two-thirds receive broadcasts that are first beamed via microwave to an antenna on top of an apartment building or estate centre. The signal is then sent along coaxial cable to viewers' homes. Though Wharf said it was busily digging to add more optical-fibre lines around the SAR, now less than one-third of the total number of cable TV-ready homes - about 400,000, according to William Kwan, who is overseeing the cable modem effort - are now connected via a Hybrid Fibre-Cable (HFC) network. In HFC networks, where data is transmitted from data centres via fibre-optic cable, which can support higher bandwidth than coaxial cable, to individual buildings or neighbourhoods. Only those 400,000 homes wil be able to use HFC-ready cable modems.