Why are there so few channels on Freeview compared to Sky and Virgin Media?

The answer to this question is very simple, there is not enough bandwidth.

Most internet users are aware of the term "bandwidth", where you can download only a limited number of files due to "bandwidth limitations".

Bandwidth also applies to television signals, Sky and Virgin Media have a lot of bandwidth, much more than Freeview.

Virgin Media have more bandwidth due to their extensive fibre optic cable network, fibre optic cable is able to transmit many phone calls, web pages and television signals at once, providing more cables are layed it can provide an unlimited amount of bandwidth.

Sky, quite obviously, sends television signals via satellite signals, which are actually microwaves. Microwaves are a form of electro-magnetic radiation as is television and radio signals used to transmit Freeview and traditional analogue signals.

The higher up the electromagnetic spectrum the higher wave bandwidth, microwaves can transmit more than television and radio signals.



Links
Freeview
Freeview Channels
Wikipedia: Freeview