As you were flipping through the channels on your TV today, you may have noticed something different about channel 70.

For the longest time it's been a rebroadcast of Seven's main signal but today it made the change to 7HD.

A spokesperson for the Seven Network has confirmed to DeciderTV that the new 7HD channel will provide different programming for different states.

In Melbourne and Adelaide 7HD on Ch70 will provide a simulcast of the main Seven channel, meaning viewers in those states will be able to enjoy Seven's AFL coverage in HD for the first time.

However in Sydney, Brisbane and Perth, 7HD on Ch70 will provide a simulcast of 7Mate content, meaning viewers in those states will continue to miss out on viewing Seven's main channel content in High Definition.

As part of the change, 7Mate (channel 73) will revert to being and SD channel.

The new 7HD channel is also available for Foxtel metro customers on channel 207, while the SD version of 7Mate is on channel 188. Foxtel customers may need to perform a rescan to find the channels.

Commencing this weekend viewers across all metro areas will be able to watch AFL games on the new 7HD channel.

What this means for Seven's coverage of the Rio Olympic games is yet to be confirmed.

Spokespersons for Prime TV and Foxtel have been approached for comment.

by Kevin Perry and Steve Molk