menuMENU    UK Free TV logo Freeview

 

 

Click to see updates

Freeview reception has changed?

Why should my Freeview reception change when I have not changed anything?

Why should my Freeview reception change when I have not changed
published on UK Free TV

From time to time people find that their Freeview box, integrated set (idTV) or Personal Video Recorder (PVR) has lost many channels without any apparent changes.

There are a number of factors to consider

Freeview 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 channels

First 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 aerials

The 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.

Cables

Make 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.

Aerial

For 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 problems

There 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?
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
Digital Region Overlap4
Two frequency interference 5
Single frequency interference6

Comments
Tuesday, 14 February 2012
E
EmlynUwchCych
5:57 PM
Llandysul

We have had no Freeview signal at all for the past 48 hours. We get our pictures from the Preseli mast.

link to this comment
EmlynUwchCych's 1 post GB flag
EmlynUwchCych's: mapE's Freeview map terrainE's terrain plot wavesE's frequency data E's Freeview Detailed Coverage
J
jb38
sentiment_very_satisfiedPlatinum

8:17 PM

EmlynUwchCych: Work in progress all of this week at Preseli which is liable to cause interruptions to service, but I doubt if this would be for any more than about 30 minutes or so at the most.

If your screen is still blank select BBC1 and carry out a signal strength check, as although there may not be any picture showing the signal will still be there, but just at a level not high enough to resolve a picture.

This said assuming that you did make the mistake of carrying out a re-tune on seeing a blank screen, as the only thing that this action achieves is to lose everything already stored in the memory, and which necessitates frequent re-scans being made in an attempt to recover the channels lost.

By the way, you are also predicted to be able to receive Freeview from the Preseli relay PSB only (limited channels) transmitter called Llandyfriog, this located at roughly 2 miles away, although with your aerial being horizontally mounted for Preseli this would cut you chances down of receiving it, Llandyfriog transmitting a vertically polarised signal.

link to this comment
jb38's 7,179 posts GB flag
J
jb38
sentiment_very_satisfiedPlatinum

9:25 PM

EmlynUwchCych: Just in case you are wondering, the third paragraph should have been "This said assuming that you did "NOT" make the mistake" etc, etc.

link to this comment
jb38's 7,179 posts GB flag
Saturday, 18 February 2012
Mike Feeney
12:23 AM
Brentwood

Lost Mux 1 and 2 completely; BBC1 analogue signal poor. Digital channels tuned in are all good.
Is something going on with the Crystal Palace transmitter that we are not being told about? Anyone else in the Brentwood area affected or is it just me?
Tried all the retuning etc. - just lost more channels today!

link to this comment
Mike Feeney's 1 post GB flag
Mike's: mapM's Freeview map terrainM's terrain plot wavesM's frequency data M's Freeview Detailed Coverage
Sunday, 19 February 2012
Thursday, 23 February 2012
P
Phil Smith
11:25 PM
Calne

My location is SN11 0QD.
I have a digital high gain aerial with 5 top and bottom elements.
My TV is a Panasonic TH-37PX70BA with a built in freeview tuner.
I also have a PVR, Panasonic DVD DMR-EX95 again with its own freeview tuner.
On both freeview tuners I can no longer receive the following channels: 8 Channel 4 , 11 PICK TV, 19 Dave, 20 Really, 29 E4+1, 46 Challenge, 49 Food Network
I have also had intermittent problems with:
12 Yesterday, 15 Film 4, 18 4Music, 21 VIVA, 24 ITV.
All were received in the past with no problems.
I have run the tests to exclude any Local analogue interference. I have also zeroid the TV and freewiew tuners before retuning them again.
I switched to Freeview fairly early so my aerial is pointed/lined up to the Mendip transmitter.
Since the Calne transmitter is now broadcasting digital, do you think I would receive the missing channels if I re-aligned my aerial to the Calne rather than Mendip transmitter?
If not, any other ideas how I can get the missing channels again.
Kind Regards
Phil

link to this comment
Phil Smith's 2 posts GB flag
Phil's: mapP's Freeview map terrainP's terrain plot wavesP's frequency data P's Freeview Detailed Coverage
Friday, 24 February 2012
A
Angela
8:32 AM

After a storm freeview hymax box wouldn't work. Satellite has been realigned but can't get hymax box to take the postcode( using a UK one obviously) does anyone know why ? Our house is an hour from the coast in Charente- Maritime. Used to work fine with an Ipswich post code.

link to this comment
Angela's 1 post FR flag
Sunday, 26 February 2012
Briantist
sentiment_very_satisfiedOwner

1:44 PM

Angela: I presume you have a FreeSAT box, rather than FreeVIEW - if so the postcodes are provided to the set-top box by the satellite signal, so it could be that the dish is not aligned to the correct satellites.

link to this comment
Briantist's 38,915 posts GB flag
P
Pamela
1:58 PM

Have no sound on free view boxes in SE19, does anybody know why? Help!!

link to this comment
Pamela's 1 post GB flag
S
sharealam
sentiment_satisfiedSilver

3:06 PM

pamela,have you checked your scarts leads they might have come loose or you might need to unplug and replug at the mains socket.

link to this comment
sharealam's 226 posts GB flag
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.