Freeview reception has changed?
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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?
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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, 5 March 2012
S
Sue Moss10:18 AM
Was the Lark Stoke transmitter out of action the evening of Sunday 4th March? When we switched on reception was intermittent then stopped altogether. This morning 5th March, the transmission is okay.
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Tuesday, 6 March 2012
S
stephanie7:43 PM
Dartford
Hi, i have a Sony Bravia 40" TV with built in freeview. Today the digital channels are not appearing or guide is not showing. Analogue channels are. i have re tuned 3 times and nothing comes up. I recieve the signal from Crystal Palace.
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stephanie's: mapS's Freeview map terrainS's terrain plot wavesS's frequency data S's Freeview Detailed Coverage
P
Pete8:25 PM
Hi, we have updated our sky multi-room - 2 boxes from (Sky+ and Sky) to (Sky+DH and Sky).
Prior to updating everything was working once we changed the Sky+ to SkyHD+ the TV in the second room will not show Sky only showing freeview.
Both sky boxes are in one room where both cables come into the house the sky HD+ is working in this room. The second room should be served by the ordinary Sky through the aerial system and operated by a magic eye.
I'm sure when we changed the box we wired it up the same.
Both TV's are Sony. Can any one help = a diagram of how to set it up would be helpful.
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J
jb3811:27 PM
Pete: Just to clarify as two interpretations can be taken from what you have said, are you meaning that the Sky+ box was changed to a Sky+HD version and with the ordinary Sky box still in situ? or is it that you are now using a Sky+HD box and with the other being Sky+? the ordinary Sky box not now being used.
Should this be the case then "if" the Sky+ box is now being used in place of the ordinary Sky box did you remember to go into its installers menu and switch the RF2 power on as well as set its RF output channel to that previously used by the ordinary Sky box? The installers menu accessed by pressing "Services" then "4-0-1-select" (on some its 0-0-1-select) this done in a smooth continuous sequence and which is best achieved if not looking at the screen whilst doing so.
The only thing I did wonder about is that as both the Sky+HD and Sky+ boxes each require two feeds from the dish was an extra co-ax run from the dish? as you were only using three before, Sky+ (2) and the ordinary Sky box (1)
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Wednesday, 7 March 2012
J
jb387:33 AM
Pete: Also meant to say, that "if" your Sky+ box is a later Amstrad DRX595 type then these do not have RF modulators fitted in them likewise nothing about this aspect seen in the set up menu, the only way of getting over the problem being to purchase a separate RF modulator from sources such as Maplin etc.
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Tuesday, 13 March 2012
D
Dave10:26 PM
Any idea why I can't get BBC and some other Freeview from Heathfield today (13 March)?
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Saturday, 24 March 2012
L
Lesley10:53 PM
ITV3 reception is showing signal average quality zero and in fact there is no picture for several minutes at a time or a broken up picture with noise. At other times the picture and sound are fine. We are in south Reading. Now we have "no signal". Some days there is no problem. Why is ITV3 so unreliable. Other channels are fine.
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Sunday, 25 March 2012
J
Joanna Mason7:14 AM
I am getting no signal on most channels at the moment. BBC1 started for a couple of minutes then broke up and now says 'no signal' as do most other channels. - ITV 3 is working. I have done re-scans. What could be the problem pease?
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P V9:20 AM
Correction to my last posting, I have "No Event Information" on menu for each (Freeview) HD channel and "No Signal" when those channels are selected. I am using the Crystal Palace transmitter as far as I am aware.
09:20 25.3.12
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