[denton]

I think a dirty feed is piggybacking off the feed that's going straight to air, where you have to work around existing presentation and CAs in the hope you'll get a clean transition to the programme you're going to show. I'm sure someone with more expertise than myself will explain it better.

I think a dirty feed is piggybacking off the feed that's going straight to air, where you have to work around existing presentation and CAs in the hope you'll get a clean transition to the programme you're going to show. I'm sure someone with more expertise than myself will explain it better.

The thing is Salford is not set up as a region  - which simply “opts out” of the network feed from London. Instead, Salford is part of the BBC’s disaster recovery scenario - so it is actually a second playout which runs separately and in parallel to the “network” London feed. Therefore, it is more akin to a second network feed, and is set up that way on purpose in case London has issues and has to cut to Salford’s feed.

Due to this, it will not be routine to “put the London feed” on air, although perhaps they should regularly do it for this Question Time live preview!

It requires some extra thinking, since BBC One North has not been created as a new service but as a way of making better use of existing DR infrastructure.

I believe that’s a simple explanation of what is going on, anyway. Someone who works at the BBC may understand in more detail.

Network BBC One plays out from London with the exact same schedule also running simultaneously and in tandem from the DR facility in Salford. Whichever site is on air is called the Leader, with the other called the Follower. The director controlling the Leader (and therefore the Follower) can be in either London or Salford... as can the live announcer. Or at least that's my understanding of how the Leader/ Follower arrangement works.

BBC One North is different from the DR, though also based in Salford. In practice it works a bit like the Nations' playout, taking the network programmes from the programmes only Clean Feed. That Clean Feed occasionally also contains "on the day" trails such as Question Time and Match of the Day, to be on the Clean Feed they need to have been enabled in the network schedule.

A dirty feed is the entire output of a network (programmes, trails, announcements).