menuMENU    UK Free TV logo Freeview

 

 

Click to see updates

Digital Region Overlap

If you can get a Freeview signal to your box or TV from more than one transmitter, you will get extra channels.

If you can get a Freeview signal to your box or TV from more th
published on UK Free TV

The old analogue TV signals provided lots of nations and regions for the public service channels, and these have large areas of overlap. Places like Yeovil, Basingstoke, Colwyn Bay, King's Lynn, York and Berwick could choose the BBC and ITV services they watched.

The old low power digital TV signals were at very low levels and reception of signals from more than one transmitter was a rare event.

All Freeview boxes automatically scan the available broadcast frequencies looking for channels, and they do this from C21 to C69. Whilst scanning, if a duplicate version of a channel is found, such as another BBC One region, they are placed in the 800-899 channel range.

The 800-899 is easy to access by pressing CH- from 1, and in most programme guides is just a single scroll up.

The transmitters in Wales also put Channel 4 on "logical channel number" 8, because the fourth position is reserved for S4/C.

Quite a few people that use the Winter Hill or Mendip transmitters (or one of the relay transmitter) will probably find that they will now have:

  • 1 BBC One Wales
  • 2 BBC Two Wales
  • 3 ITV1 Wales
  • 4 S4/C
  • 8 Channel 4
  • 16 QVC
  • 72 CITV
  • 86 S4/2
  • 801 BBC One West/North West
  • 802 BBC Two England
  • 803 ITV1 West/Northwest
- or -
  • 1 BBC One West/North West
  • 2 BBC Two England
  • 3 ITV1 West/Northwest
  • 4 Channel 4
  • 16 QVC
  • 72 CITV
  • 86 S4/2
  • 801 BBC One Wales
  • 802 BBC Two Wales
  • 803 ITV1 Wales
  • 804 S4/C


What can I do about this?


There are basically three options.

OPTION 1: Live with it. If the signals are strong enough you get a few extra channels (S4/C has English subtitles). There are techniques for sorting out the channel numbers below, but any future automatic scan will restore the channels to the order you now find them in.

OPTION 2: You can clear the all of the channels from the box and manually scan for the multiplex from only one transmitter. For the details, see the transmitter pages

OPTION 3: If the Freeview box has no "manual add" option, the only technique left is to pull out the aerial, start the automatic scan and insert the aerial just before the lowest channel number appears. For example, Winter Hill this is C54.

Some Freeview boxes will show a "percentage complete" as they scan, under this scheme C21 is "0%", C22 is "2%", C42 is "42%", C54 is about "66%".

Even if you manual scan, many boxes will scan during the night for new channels and may still add channels in the 800-899 range.

Help with Freeview, aerials?
How do I get a test card with Freeview1
I would like to know if it is possible to receive UK terrestrial Freeview servic2
I have been told I would receive too much singal from my Freeview tansmitter as 3
Can my Freeview box receive more than one BBC and ITV region?4
Is it true that my 87 year old mother is entitled to a FREE upgrade when the ana5
[][][
In this section
Official aerial installers guide to the TV spectrum future1
Which free digital TV system will give me the most reliable reception?2
High pressure causing channel loss through "Inversion"3
Freeview reception has changed?4
Two frequency interference 5
Single frequency interference6

Comments
Tuesday, 27 September 2011
Liz Falconer
1:35 PM

jb38: Benny London:

I can't find anyone in my area who has STV HD. I did post on local forum but haven't had a reply.

Benny I don't get the channels in their proper place at all so just deleting the extra 800 channels won't work.
I do have the latest firmware on my PVR and all the other channels are working perfectly so can't be the television.
My tv is a Panasonic and not that old.

I really appreciate your input though.

It's just really frustrating not knowing why this is happening to one channel only. I know this to be a fact as I've gone through them all.

link to this comment
Liz Falconer's 13 posts GB
Liz Falconer
8:13 PM

Benny I forgot to say that I tried changing the v-format and that made no difference so am completely stumped. :(

link to this comment
Liz Falconer's 13 posts GB
J
jb38
sentiment_very_satisfiedPlatinum

9:54 PM

Benny London / Liz Falconer:

Benny London: No, I am not in the least offended! as what you have said is quite valid regarding HDMI difficulties when used with certain types of equipment, the reason though that I didn't bring that issue into the equation was because of the problem being on a single channel, as HDMI compatibility problems don't in the general run of things single out a particular channel to cause a problem on.

There in again, when dealing with digital signals all sorts of odd problems can strike!

Liz Falconer: I think you should have a look in the phone book for a TV shop located in Wick and give them a tinkle to enquire if they have heard of any problem with STV HD from the Rumster Forrest transmitter, as this point really needs to be verified, because if its definitely not a fault at the transmitter then it has to be the boxes, because good as Humax boxes may well be, and I have three, they are not without their faults.



link to this comment
jb38's 7,179 posts GB
Liz Falconer
11:29 PM

Okay this is getting weird!
I was watching STV HD and there was no flicker and then noticed the STV logo has gone!!!
Still can't tune into Mux Channel 24 but wonder whether this is connected since it contains STV?
I am trying to find out about the Rumster Forest transmitter.
I'll just be happy if the flickering stays away! :)

link to this comment
Liz Falconer's 13 posts GB
B
Benny London
11:36 PM

Liz Falconer: Digital TV has a very complex set of standards which allow for a multitude of variations in formats. Consequently, there can be all manner of differences between TV channels, differences between programmes on the same channel, and even differences during an individual programme as it goes in and out of commercial breaks. Often, transmitted streams don't even comply with the standard. HD streams have the additional hassle of copy protection, which is a whole can of worms in itself.

Generally, boxes cope pretty well with the many complex tasks they have to do, but occasionally certain channels will not work on certain boxes. Such is the nature of digital TV.

It's likely there is something specific to the STV HD stream which is tripping up your equipment, and this can occur anywhere in the path from tuner to screen.

I can't obviously analyse the transport stream from this far away(!!) but I'd be astonished if the streams for the individual HD channels were all formatted identically. Or that the data streams presented to the TV had identical formats for every channel.

If I were in your position, I would definitely want to try the Hummy with a different telly. It's a matter of eliminating possibilities and trying to pin the problem down to a specific piece of equipment. (BTW I assume you have HDMI directly from Hummy to Panny. You're not going via an amplifier are you?)

Regarding your tuning problem... You could try attenuating the RF signal while you auto-retune (a lead with only 1 wire connected might do). The idea is to get the signal from the aerial so weak that the Humax can only just about pick up the contents tables from the desired transmitter but won't detect any other transmitters. Afterwards, you can put the normal lead back again.

Don't forget to unplug the Hummy before you fiddle with the aerial connection. That warning notice on the cover is there for a reason!

link to this comment
Benny London's 2 posts GB
Wednesday, 28 September 2011
Liz Falconer
11:25 PM

Benny: Well the flickering has stopped on STV HD so I am really hoping it stays away.
I do wonder whether they have been working on this channel as the STV HD was visible during part one of a programme, visible in part two and missing again in part three!
Yes the HDMi is direct to the telly and not via an amp.

To be honest I don't really feel like moving the hummy to another telly as I have a back problem.

I do have all the channels tuned in correctly apart from Mux Channel 24. I might indeed try the attenuator as you suggest. Thanks!

link to this comment
Liz Falconer's 13 posts GB
Thursday, 29 September 2011
Liz Falconer
1:10 PM

jb38: Benny:

Well I've just found out that the flickering on STV HD was a broadcast fault which has now been sorted! Would have been nice if they'd told their viewers!

I still can't get Mux Channel 24 to tune in properly but think I will wait until this weird weather ends before trying again in case this is interfering with the signals.

Thanks ever so much for your help both. :)

link to this comment
Liz Falconer's 13 posts GB
J
jb38
sentiment_very_satisfiedPlatinum

2:31 PM

Liz Falconer: Thanks for the update, the content of somewhat confirming my earlier mentioned suspicion of your problem being caused by a broadcast fault, albeit still with the lesser possibility of a problem existing with the Humax.

Anyway, as far as Mux Ch24 is concerned, I would like you to blank out anything stored using the scan without the aerial procedure, then manually tune in Mux Ch24 "only", as the box only having that channel stored is a better way to test things, giving an update once done as far as the signal strength / quality is concerned.



link to this comment
jb38's 7,179 posts GB
Wednesday, 9 November 2011
B
Bob Loader
sentiment_satisfiedBronze

12:44 AM

Thanks Mike for your reply (2 Nov). Most of the time I have perfect reception, 10 on the signal "quality". However during the poor reception periods the level goes to zero. The main BBC channels are not affected.
I thought you may have some idea if they were still working on individual multiplexes
Yes I do receive Wrekin signals quite strong, I can see the Wrekin but I prefer to use the Sutton transmiter direct

link to this comment
Bob Loader's 40 posts GB
Saturday, 26 November 2011
B
Brian Thwaites
2:19 PM
Chelmsford

very usefu service.......thanks a lit.

Have discovered the BBC and a few others in the 800 region but channel 12 (yesterday) has disappeared...please is it still on air or not available on Sudbury???

link to this comment
Brian Thwaites's 1 post GB
Select more comments

Your comment please
Please post a question, answer or commentUK Free TV is here to help people. If you are rude or disrespectful all of your posts will be deleted and you will be banned.







Privacy policy: UK Free Privacy policy.