Wednesday, September 30, 2009

Freeview Retuning

For those with Freeview it would have been difficult to avoid those annoying boxes that seem to appear every time you change channels telling you about the re-tuning that needs to be done today. It got mentioned on both GMTV and Breakfast this morning along with some explanation; but for those still left puzzling here's the reason.

To start with a little bit of technical information is required. All the channels are split into groups called Muxes (singular: Mux, short for multiplexer) these are internally labelled as 1, 2, A, B, C, and D and are in order of strength.

BBC gets Mux 1 to itself, this is to ensure that anyone able to get Freeview can at least get the BBC services which they are, after all, paying for. ITV and Channel 4 divvy up Mux 2, and every other channel gets spread throughout the lower Muxes.

For those paying attention you might have noted the absence of channel Five. Now those of a certain age might well remember the problems when this channel was introduced. Essentially back in the day when the most common connection between a VCR and the TV was the aerial lead, you had to tune in the TV to the frequency the VCR was sending down the aerial. Guess what frequency they used to broadcast this new channel? Not quite but damn close to that used by the majority of VCR equipment. Add to that the fact that as a lower strength frequency meant that a lot of the country couldn't get channel Five you 'd think that when it came to the new shebang that is digital someone would take note of history.

Nope, Five was shoved into Mux A which parts of the country still couldn't get.

So this great re-tuning is to shunt Five from its dismal hole up into the numbered Muxes with the big boys. At the same time they're clearing out Mux B ready for the HD broadcasts that pretty much no-one in the country has the equipment to receive and can't buy yet (but HD caught a lot of people on the hop and it's good forethought so no real negatives from me)

The price to pay is that to make room some of the numbered Mux channels such as ITV3 will be moved down to a letter Mux, which some can't get. So some parts of the country will gain a couple and lose a couple of channels.

However all the major channels won't move, so BBC1 etc. won't suddenly go blank on you.

Now for their stated reason as not to interrupt peak viewing they're performing this switch at noon today. Fair enough except for all those trying to record something that occurs between then and when they get home from work that might be on one of those channels doing the Mux Shuffle. This is not helped by the small fact that no official documentation has been released to state which channels are moving or to where. So if you're recording something on one of the minor channels (or Five) at these times cross your fingers in the hopes of recording it.