@XSK.The set box ia basically a receiver.You need it to decode the digital waves.About 20channel are available once u install one.The 1st phase which was implemented in dec/jan2010 covers a radius of 140km from nairobi.
The Digital Video Broadcasting(DVB-T) technology bn in existence since late 80s.most of the set box targeting the mass market are mature.
Comes in two forms, SD or HD type.A HD receiver cn decode both SD&HD transmissions.Currently all channels are free to air.might take another 10yrs or more to get pay channels.Most of europe,asia and Africa use or will use DVB-T technology.
these gadgets also available for vehicles/computers. see
http://www.alibaba.com/member/ke108524083.html