Freeview reception has changed?
Brian Butterworth published on UK Free TV
There are a number of factors to considerFreeview is broadcast on digital multiplexes. This means that, once broken down into a stream of bits, each television channel is combined into a single transmission of 1s and 0s. This means that reception is of the multiplex first if this is lost it affects all the channels in the multiplex in the same way.
The signal strength received by the box or TV for a particular multiplex from a given transmitter determines if the data can be received or not. So, a poor signal results in no data, an adequate signal in perfect data and a low signal in either none or all.
Poor digital signal levels do not result, as they do with old-fashioned analogue television, in a sub-standard picture or sound. Poor signals often result in a perfect data-stream, but are prone to periods of no reception. Sometimes this will be for hours, but can also be several times a minute when caused by induction from fridges, freezers, central heating systems, two-stroke scooters, baby monitors and so on.
If you have lost ALL your Freeview channelsFirst disconnect the aerial lead from the Freeview box or TV set and reconnect it and then follow this reset procedure to scan for channels again. If this does not result in services being restored, check the Freeview transmitters page to see if there are any engineering problems with your local transmitter.
How to check all cables, connectors and aerialsThe RF connectors need to be in very good condition to work. There are two general types:
Factory-fitted connectors are very reliable as they cannot easily be taken apart, but they can be damaged by wear and tear. On the female-type the central section is often composed of two parts which can often be forced apart, resulting in a poor connection you can push them back together if this has happened with a pair of tweezers. On male connectors if the central pin is damaged, you will need a new cable. If there are any loose partials in the connector, remove them.
Another problem with these cables is that quite easy to sprain the connector at the back which causes little obvious external damage, but disconnects the internal connection. This happens often when a set-top box is pushed backwards into a cabinet.
Hand made cables can also suffer from similar problems to factory made ones and they are also prone to accidental damage from a cable being pulled. If such a connector is not firmly attached to the cable, the connector may need refitting.
CablesMake a visual check of the cables. There are a few basic checks:
If the cable has been slashed or cut, it will not be very effective or reliable. If such a cable is fitted externally, this can allow rainwater to enter the cable and this will reduce the signal levels.
You can easily damage an RF cable by crushing it, for example in a door. If the outside of the cable has a permanent kink in the cable or has been very tightly looped, this could be the site of damage.
AerialFor reliable and effective Freeview reception, a rooftop aerial is required. It is hard to make a visual check of such an aerial without putting yourself in potential danger.
You can make a visual check of the route between the aerial and the transmitter. Any form of obstruction will damage the digital signals. In particular trees coming into leaf, as these will leech the signal before it reaches your aerial. This applies to both trees adjacent to the aerial and at a distance.
Another common problem in cities is building work. A large crane will often change position many times during the day, and if this is between your aerial and the transmitter this can reduce the signal levels in an unpredictable way.
If your system uses a booster, the power may have failed. Check the fuse to the power to the booster.
Weather problemsThere are two main weather problems that effect Freeview reception.
The Inversion Effect: please see What is the Inversion Effect and why does it effect my Freeview TV reception?
Wind: high winds sometime can dislodge the aerial this results in a poor signal.
Rain: poor or old cables can fill with water and this results in a poor signal. If this happens, the cables will require replacement.
Help with Freeview, aerials?
Monday, 11 June 2018
Bury St. Edmunds
Hello there.... freebview changed last week in East Anglia and how I have lost the bbc channels.
I have actioned the scan and reset and full installation many times during the week but the first channel to come up in itv.
Postcode is IP31 3QS
I have also tried a booster with the tv.
The lounge tv is fine .. bbc is there but on the kitchen tv, ( same aerial ) no bbc channels at all
Could you help please ?
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Tuesday, 12 June 2018
If one TV is getting the BBC channels well then that suggests either a poor connection to the one having problems, or it has a fault (but probably not likely, though should be considered).
Try disconnecting the aerial feed to the troubled TV and refit all the plugs and sockets (poor contact can cause this problem). Then do a retune without the aerial connected followed by a retune with the aerial plugged in. Then check the signal strengths for all the channels, it needs to be between 60% and 85%. Any higher or lower will cause prioblems. Remember that different make/model sets have different tuners, some being more susceptible to overload than other or being less sensitive so needing more signal.
There is also the poissibility that your aerial may not now be ideal for the currently transmitted signals, you now need a wideband type, as COM7 and COM8 are now on channels 55 and 56.
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Saturday, 30 June 2018
Sunday, 1 July 2018
Monday, 2 July 2018
You should be getting good reception of all channels available from the Sudbury transmitter. That is just 35km (under 20 miles) away and there are no significant hills between.
Please check that your TV is tuned correctly to the Sudbury transmissions. They are on channels 44, 41, 47, 58, 60 and 37. The main BBC SD transmissions are on the BBCA multiplex on channel 44. There is no known problem with the transmitter, else there would the thousands of complaints - but there aren't.
So you could have a problem with your equipment. Start by checking all the aerial cables and connections and then ensure you are correctly tuned by using the manual tuning facility of your TV (see the User Manual for how to do that). Whilst checking you are using the correct channels, look at the signal strengths being reported on that same settings page. It needs to be between 60% and 85% strength (not quality). If it is higher than you have too much signal, but that is unlikely. If it is too low then you need the assistance of an aerial installer to correct the low signal strength.
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Sunday, 15 July 2018
Monday, 16 July 2018
You should not have done a retune at all! That will never bring back missing channels. It is highly likely that the current weather is causing your loss of some channels.
You will now need to manually retune to regain the chanels your wiped. Put your post code into the Digital UK Coverage Checker at Digital UK - Coverage checker scroll down to the details for the Newhaven transmitter and not the channel numbers. Use to to manually tune your TV, your User Manual will tell you how.
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Tuesday, 17 July 2018
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