The UK digital terrestrial broadcast platform -- branded as Freeview -- consists of six DVB-T standard multiplexes and one multiplex supporting DVB-T2 for HD.
The platform is compliant to the DVB-T standard, and uses a UK specific profile of MHEG-5 to provide Interactive Services. MythTV supports both standards and can be received using a standard DVB-T capture card.
A full channel list can be found on the Digital TV Group's website. It is oft reported that channel ordering is incorrect with MythTV and Freeview; UK Channel Assignments covers rearranging channels.