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aerial' for analogue reception, but as they are generally unsuitable for Freeview reception, they have now generally been replaced by the Yagi type.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, 4 June 2011
S
Steve10:39 PM
- Freeview on Oxford TV transmitter | ukfree.tv - independent free digital TV advice -
John - If you look at the transmitter page; BBC is 16QAM and ITV 64QAM with same strength.
Put simply; they are trying to put 4 times as much through the ITV.
Will probably solve itself in September with switchover. You might find a cheap booster will help now. (LL145HD)
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Sunday, 5 June 2011
J
John7:03 AM
Aylesbury
Steve - Thanks for that info Steve. I already have a powered splitter box, should that do the same job as a cheap booster?
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John's: mapJ's Freeview map terrainJ's terrain plot wavesJ's frequency data J's Freeview Detailed Coverage
K
KMJ,Derby12:23 PM
John: Your signal strength and quality suggest that there is nothing wrong with your signal, it is most likely intermittent interference being picked up. If you have any fly leads are these also good quality double screened coax? Is it possible to match the break-up with any equipment turning on or off, or something being used in the locality such as a lawn mower or power tools? If the interference is being picked up by the aerial amplifying the signal further will not improve matters and could result in too much signal being delivered.
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S
Steve2:34 PM
Peterborough
John - if you are not using the powered splitter box and start to it will probably help if a booster amp would have helped. And if you are already using it a booster will probably not help.
KMJ's points make sense. If you haave two outlets fron the aerial does the problem occur in both?
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Steve's: mapS's Freeview map terrainS's terrain plot wavesS's frequency data S's Freeview Detailed Coverage
J
John8:56 PM
Aylesbury
KMJ / Steve. Thanks very much for those comments. I have checked the fly leads and they are the good quality ones. Today it seems a lot better so I do agree with you in that it maybe an outside influence or possibly just atmospherics. Also, I ran into someone from the other side of our town who said they were having the same thing yesterday so my money is on the weather. Thanks again for the advice.
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John's: mapJ's Freeview map terrainJ's terrain plot wavesJ's frequency data J's Freeview Detailed Coverage
Monday, 6 June 2011
D
david roberts10:02 PM
i live in new milton hampshire post code is bh25 and the signal is terrible can any one help. regards dave
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Tuesday, 7 June 2011
S
Steve1:03 AM
dave - with so little information; no-one can help.
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Sunday, 12 June 2011
R
roy12:55 PM
Malvern
i live in Great Malvern wr142tl
Can i receive freeview from malvern transmitter from indoor aerial
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roy's: ...
S
Steve1:20 PM
... UK digital TV reception predictor
As you seem to be on top of the transmitter you can probably receive with no aerial at all - or a sketchley loop.
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Monday, 13 June 2011
roy: You are predicted to get excellent reception - from a rooftop aerial. Indoor aerials are not reliable for Freeview reception, even very close to the transmitter as you are.
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