How are live televised broadcast done?

all the cameras are sent to a mixing board that has switches to choose which camera to bring up to the preview window and what graphics to load.

The audio just like the video goes through a mixer

The tricaster is one example of a mixing board

it is like Kevin says it wasn't always as simple as it is today , today its all digitize computerized pretty much everyone involved is an engineer to one degree or another ..

when I was much much younger I went to the new school of contemporary radio and television I always thought being DJ weather forecaster of camera man would be funny and great .

check it out it was great the only college of its type in the US as I know just dedicated to this , if nothing else you will find there site interesting all the fields of study you have to go through for various jobs in the field including computer programming and IT engineering degrees and more ..

http://www.thenewschool.us/

this is where a lot of my knowledge, degrees ,education came from in the many area's including computers and programming graduated started when I was 16 years old in 1976 finished in 1981 including 2 years at a local community college required as part of the training..

finished with a degree in electronics engineering , first class radio telephone operators licence, a degrees in computers and programming, advertising, ad writing, editing , a degree in broadcasting both radio and television..

land me a job in radio, college and commercial stations doing oldies and disco, cable setting up and keeping things running for local access, I was a VJ about 2 year before there was an MTV for a bit Remember " wayne's world" there was a certain amount of reality to that for a short time.. it was also the begining of my interest in computer and Networking through radio :)