Freeview reception - all about aerials
Updated 8th January 2014.
Your ability of receive all the Freeview transmissions depends on the suitability of aerial
- the design style,
- the "group", and
- its physical location.
Standard type - Yagi aerial
The standard type of TV aerial is known as the Yagi aerial. It is mounted on a pole, and consists of a rod with a reflector (shown green) at the back and many spiky elements (in grey) at the front. The connecting cable connects to the element nearest the reflector, known as the driver (shown in blue).
These Yagi aerials are directional and so pick up signals best from a transmitter that the rod points towards. The more elements the aerial has, the better it picks up a signal and becomes more directional.
A standard-type aerial is all that is required for digital TV reception in most places. These antennae have between 10 and 18 elements and a single reflector. These are recommended for new installations for good digital television reception, but will more often than not function perfectly in good reception areas.
Typically these aerials are designed to receive only some transmission frequencies - see "groups" below.
High Gain aerials
These aerials are designed for poor digital reception areas, and have two reflectors. For maximum signal strength, some digital high gain aerials have up to 100 elements. Since the switchover to digital-only transmissions back in October 2012, most UK households now have good quality digital TV signals.
A more expensive aerial is only required where the signal strength is low, but can often provide the whole Freeview reception where it might otherwise be impossible.
The CAI (that represents aerial installers) has four standards for digital TV aerials. The highest standard "1" is for homes on the fringes of coverage areas, intermediate standard "2" is suitable for use within the coverage area; minimum standard "3" is for good coverage conditions.
These aerials can be either wideband, or receive only selected frequencies - see "groups" below.
Grid
You may haved used a 'Grid aerial' for analogue reception, but as they are generally unsuitable for Freeview reception, they have now generally been replaced by the Yagi type. However in some places a Grid aerial installation may work for Freeview: otherwise replace with a standard Yagi aerial.
Indoor
Indoor aerials are generally not suitable for Freeview reception. In areas of good signal strength it is often possible to receive some transmissions. Even where an aerial works, people often find that may get interruptions to their viewing (or recording).Loft mounted
Loft mounted arrivals are not generally recommended for Freeview reception, as the roof tiles and plumbing will degrade the signal. Some compensation for this loss of signal can be made by using satellite-grade cable to connect the set top box to the aerial.Positioning
The best position for a TV aerial is mounted outdoors, as high from the ground as possible, pointing directly at the transmitter. The signal can be blocked by hills and tall buildings. It should be positioned away from any other aerials.Horizontal or vertical?
The transmitter will either use vertical mode which requires the elements of your aerial to be up-down, or horizontal mode which requires them to be level with the ground.Groups
Both analogue and digital television is transmitted the same group of transmission frequencies (known as channel 21 through to 60). A coloured marking on the aerial shows the group.To create the best possible analogue picture, TV transmissions from adjacent transmitters have been designated to several different groups of frequencies. By using an aerial that receives only the channels in the correct group, the analogue picture can be kept free from interference.
To receive Freeview transmissions from the same transmitter it has been sometimes necessary to use frequencies that are not part of the transmitter's normal group. When this has occurred, the aerial will need to be replaced with a "wideband" aerial (also known as group W) - one that covers every group.
As Ofcom is planning to move the TV frequencies again - perhaps as soon as 2018 - it may be wise to use a wideband aerial if you can to ensure you can keep viewing Freeview for many years to come.
Help with Television sets?
Saturday, 20 August 2011
K
kenny12:42 AM
I live in boldon tyne and wear ne360pu and signal on itv channels is breaking up, bbc ok, do I need a better aerial, this has started in last two weeks
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Wednesday, 24 August 2011
K
Kevin Regan6:07 PM
Chelmsford
Hi I have just fitted a new aerial on a pole on the side of my house to go with my new tv which has Freeview. The aerial is pointing towards the Sudbury transmitter. I live in the CM2 9JT area, I can only receive about 20 channels. I have tried all the different forms of tunning but still no luck. Should I use a meter to set my aerial up. Hope you can help, many thanks Kevin.
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Kevin's: mapK's Freeview map terrainK's terrain plot wavesK's frequency data K's Freeview Detailed Coverage
kenny: I would have a look at Single frequency interference | ukfree.tv - independent free digital TV advice .
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Steve P9:40 PM
Kev R - are they all on one or two multiplexes? Have a look at the Sunbury page here.
You have strong options!
UK digital TV reception predictor
You need kit and expertise to set the aerial up properly for weak signals. Much harder than it was with analogue, as there is delayed response.
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Thursday, 25 August 2011
P
Phil Clarke4:10 PM
Hi, I'm using a old standard aerial (18 element - flat reflector plate) in close proximity to Chesterfield transmitter. Don't think it is wideband !
Getting all FReeview channels on two tv's with a basic splitter in cable - except those on channel 43 (CITV etc.) Signal reported as 9% very poor quality. Does anybody know if a wideband aerial would solve this?
thanks
Phil
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KMJ,Derby4:46 PM
Phil Clarke: If the problem is being caused by the use of a group A aerial - (does it have a red stopper at the end of the boom?)-then yes a wideband, or a group K, would give improved reception of the COM muxes. However if the problem is interference, possibly from Emley Moor which is using this frequency until 7th September 2011. It should be noted that the COM muxes from Chesterfield are currently being transmitted at reduced power.The Digital UK postcode checker shows reception improving in September when Emley Moor stops using the same frequencies as Chesterfield and again on 12th October 2011 when power is raised on the COM muxes to 400W
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KMJ,Derby4:52 PM
Phil Clarke: Typo, should say: However if the problem is interference.......then a replacement aerial might not make any difference.
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Steve P6:02 PM
Phil C - Unless you are greatly troubled by what you do not get, I suggest waiting until all areas anywhere near you, or to tx used by you, have completed changover.
Anything you do now may eventually prove ineffective or wasted.
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David Corrick10:17 PM
Cardiff
I live cardiff cf140rp which uses thw wenvoe
transmitter
I Currently have a wide range aerial on the chimney stack of my Bungalow
Tuned to wenvoe I receive channels
c41 c42 c44 c45 c49 I cannot pick up C47
I am also picking up c54 from mendip transmitter. The quality of picture varies from day to day and during a day and I also get distorted sound some of the time.
bbc 1 and bbc 2 wales are the best channels but they sometimes break up. We Live in the country but the is a large tree 50 mtrs away from the aerial blocking the direct line of site of the transmitter.
DOI stick with freeview or change to freesat
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David's: mapD's Freeview map terrainD's terrain plot wavesD's frequency data D's Freeview Detailed Coverage
Friday, 26 August 2011
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Jim F12:32 PM
David Corrick: C47 on Wenvoe carries the HD channels only - you'll need a Freeview HD telly (or digibox) to receive it ("HD ready" on the TV doesn't mean it has a Freeview HD tuner, just that it has HDMI sockets).
At 13km from the transmitter, you're more likely to be getting signal overload causing the picture break-up, even with the tree in the line of sight, but traffic on the M4 motorway might affect your signal.
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