Freeview modes
Brian Butterworth published on UK Free TV Two of the Freeview multiplexes (collections of channels) broadcast in one mode known as "64QAM mode, FEC=2/3,", and the other three broadcast in another mode called "64QAM mode, FEC=3/4".
The " FEC=2/3" mode provide a more reliable signal than a "FEC=3/4" mode signal at the same power level, but there is a trade-off that means less digital data can be carried.
This diagram shows the current channels carried on the Freeview system. The wider the box, the more bandwidth is used to carry the pictures. The more bandwidth used for a service, the better the picture quality.
Boxes split horizontally denote channels that occupy the bandwidth at different times of the day.
The third line shows the configuration of the BBC "B" multiplex switchover which is used for HD and is in another mode DVB-T2 256QAM.
64 QAM (3/4) mode
In this mode, the digital TV signal is transmitted in groups of 64 symbols. The "forward error correction" is 2/3, and this results in a bitrate of 24M.1b/s (megabits per second). This can be used to carry up to eight simultaneous television channels.64 QAM (2/3) mode
In this mode, the digital TV signal is transmitted in groups of 16 symbols. The "forward error correction" is 3/4, and this results in a bitrate of 27.1Mb/s. This can be used to carry ten simultaneous television channels.Help with Television sets?
Saturday, 1 December 2012
S
Sam D10:50 AM
Hi I live in postcode area HU32HP
On thurday I got a new toshiba tv with built in free view. Before that I was using a freeview box which picked up all the channels but since plugging the new tv in the only channels that are getting picked up are the bbc channels which are still poor quality, I've also tried plugging my freeview box into the tv but that's not picking any channels up at all now
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Sam D: Royal Mail lists 47 addresses within that postcode. On Google I can see a tower block and that is it.
If you are using a communal aerial system, then if it is that which is at fault, then you need to notify whoever is responsible which might be your landlord.
If neighbours are also affected, then this obviously adds considerable weight to this being a possibility.
It may be that only some neighbours are affected.
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Saturday, 5 October 2013
G
Guy12:40 PM
WE seem to have recently lost PSB Channels on 2 TVs but receive it okay on a third. ITV1, ITV2 & Channel 5 affected.
We have a signal booster in the loft and we have tried auto retuning the affected TVs) both Fergusons with internal freeview receivers. Bit still we have not recovered the missing channels. Any suggestions?
SN4 7 postcode.
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Guy:
If your working tv is receiving through a digi box then you may have an issue with your reception.
A tv tuner needs a minimum of 45db to work correctly
A digi box needs a minimum of 40db to work correctly
This difference means that a digi box will perform better than a tv tuner.
Also some tv brands can cope better with poor reception.
You could try moving the tv that doesn't work to the same location where you have a working tv, if your channels work in that location then there are issues with wiring to the other locations
regards
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jamie's: mapJ's Freeview map terrainJ's terrain plot wavesJ's frequency data J's Freeview Detailed Coverage
Sunday, 4 May 2014
J
Josie Bailey7:00 PM
when i try to rescan my logik L22DVDB20 television it freezes at 19%
I have tried it in other rooms of the house where televisions are OK, but it still freezes at 19%. Consequently I have lost quite a few channels
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J
jb388:33 PM
Josie Bailey: Try removing the aerial "before" carrying out and auto tune and check if the scan still freezes at 19% or possibly carries on to 100%, if it does complete a full scale scan then reconnect the aerial followed by carrying out a normal auto-tune.
If though its found that the situation has not changed, then carry out a "first time installation" as described on page 26 of your manual, should you still have it?
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Sunday, 6 July 2014
J
Jackson G2:21 AM
Based in Newcastle Upon Tyne.
Would this explain a strange issue - Samsung TV about a year old, all '4' channels when selected, restart the TV and cut out. Happened first with 4music but now spread to e4, More4, Film4. Only one that works is normal channel 4. Any suggestions?!
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jb389:53 AM
Jackson G: The problem referred to could point to a software glitch having occurred in the TV therefore you should try carrying out a "first time installation" on the set, this also being known as a "default setting" / "manufacturers reset" or similar sounding name, as problems of an odd nature such as described are frequently rectified by using this procedure.
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Monday, 7 July 2014
J
Jackson G10:49 PM
Hi there - your suggestion did not work however thank you for your quick and informative response - way faster and more helpful than Samsung! We have found out both e4 channels have a poor signal (3%) so are considering a booster? We still don't really understand, as the picture is 100% okay for 5-10 seconds before cutting to black and restarting the television!
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Tuesday, 8 July 2014
J
jb3812:31 AM
Jackson G: Thanks for the update, however in view of the fact that the situation has remained the same even after having carried out the reset on the TV then this somewhat complicates the issue, therefore I would like to know the outcome of the following test.
Remove the aerial input from the TV followed by selecting any of the problem channels mentioned, (E4 / More4 / Film4) which of course will not result in a picture!, the reason for the test being to find out if the TV still cuts out then restarts when any of the channels mentioned are selected, or only does so when the actual signal being received?
By the way, all of those problem channels are transmitted on the same multiplex, namely PSB2 (C54 - 738.0Mhz) "including" the channel you report as being OK, channel 4. On the other hand E4+1 is broadcast on COM5 (C59 - 778.0Mhz), does selecting this latter channel also affect your TV in a similar fashion to the others containing 4?, and is the 3% signal strength you report referring to this channel?
As far as signal strength is concerned, it would be of assistance to have knowledge the location you reside in within the Newcastle area, as there are quite a few reception dead spots to the North of the Pontop Pike transmitter.
Finally, could you please indicate the model number of Samsung in question.
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