We have BBC 1 and 2 available along with Channels 3 (ITV), 4 and 5. The BBC channels are paid for by our TV liscence which in 2011 is £145.50 a year. An increase of nearly 50 pounds on 1999's figure (according to http://www.mediauk.com/). This pays for the BBC's broadcasting costs all across their company including radio which means thier main channels do not carry advertisments. The other channels carry advertisments to fund their broadcasts.
The BBC
14 years after the BBC was founded by Scotsman John Reith the first TV broadcasting system was set up.
Originally two systems were set-up and used on alternative weeks but eventually the 'Marconi-EMI's 405-line system' was chosen and used through until the 1960's. 405 referred to the 'lines' used in the 'interlace'.
The broadcasts originally where few and far between but the popularity boosted quickly and widely.
Broadcasting standards.
These in basic are how analog TV signals are encoded to send and recieve correctly. For example PAL is the one used in UK, along with most of Europe, Asia and Austrilasia. This runs alongside our power supply which is 50Hz persecond. So channel broadcast 50 fields (of alternative lines) with at the speed of 0.02 seconds become undetectable and merge together to form 25 frames. It also contains contains 625 lines of resolution. With NTSC, used throughout America and other countries the two main differences are that the electrical supply is 60Hz so in response there are 60 fields and 30 frames created. Also the resolution is smaller with 525 lines. Because of these reasons, the two cannot be played on differently set players. They may need to cut out or add frames which seems jerky and the set may compensate for the number of lines with black lines.'http://www.wisegeek.com/what-is-the-difference-between-ntsc-and-pal.htm'
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