Digital Region Overlap
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:
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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.
12:42 PM
Harlow
hiya bob i live in harlow essex CM19 5SN....have recently installed a slx 48 element aerial on roof..i have run roof lead to philex 4 way booster from there to lounge freeview tv and bedroom humax 9200t freeview pvr to freeview tv..if aerial leads (with or without booster) are connected straight to freeview tvs there is no problem.but if i put aerial thru humax box the ITV,C4,5,MORE channels are stored(manually)but then if i try to record and watch another tv channel or playback something on hdd the humax loses that itv ,c4,c5 more...the humax signal detection shows 23% strength and 100% quality...aerial is pointing to CP ,but should i be useing hemel.sandy heath,bishops stortford or which transmitter?? i am sure this is a aerial prob
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tony's: mapT's Freeview map terrainT's terrain plot wavesT's frequency data T's Freeview Detailed Coverage
tony: Your strongest signals come from Crystal Palace, and you should be getting very good reception.
Did you use satellite-grade cable to connect the aerial to the first TV point?
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2:02 PM
hi there.
why is it when the weather is not so great. a bit windy, and i lose all my itv channels. bbc seem ok.
i have freeview channels only.
am located in the village of Cubert in Cornwall.
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11:59 AM
RIGHT DONE WHAT IT SAYS ON HERE AND STILL NO joy still have itv wales and s4c but never had this problem before the manual scan dosnt help and I dont no what the multiplex thing is all about and I cant watch them 800 s channels as its all filth
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Stephen: The 800-899 channel range is not for "fith", that is 90-99.
800-899 is for dupliate regional versions of channels.
If you want, you can delete all the channels and add in the five/six/seven multiplexes yourself.
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9:31 PM
Redditch
I have purchased one of these DVB T mini tv box by Neostar. Good receiption but cannot get the 5 terrestrial channels. I live in the B98 7LL Sutton Coldfield.
Any ideas
Thanks
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Alan's: mapA's Freeview map terrainA's terrain plot wavesA's frequency data A's Freeview Detailed Coverage
11:10 PM
Craigkelly transmitter, location KY6
After second stage DSO I can't receive mux NEW7 channels, appear to have a group K aerial, as all other muxes have good reception. Which option would be best, get a wideband aerial fitted, a group C/D diplexed to the existing K band or replace the K band aerial with a logic periodic?
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11:12 AM
Bob W. NEW7 does not exist at present, if it ever will. The whole question of local tv services is still under discussion, there is serious doubt as to whether it would be viable.It is also worth noting that in the event of additional services becoming available they would be transmitted at much lower power than the other muxes, and targeted at specific areas. The gain curves for tv aerials show a K band peaks around C52 so would be better than a wide band aerial of similar size for receiving NEW7 if it did become available in your location.
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