Home TV signal boosters
A Freeview signal booster, also known as an aerial amplifier can help improve digital TV reception in fringe areas which get a weak Freeview signal from a distant DTT digital TV transmitter or where nearby hills or nearby obstructions like tall buildings cause poor reception.
Several different types of TV signal boosters are available and all have different applications:
TV Distribution Amplifier
Whichever type of TV amplifier you choose, to get the best results in improving Freeview reception quality, we recommend fitting the digital TV signal booster as close as possible to your TV aerial, rather than behind your TV, where it will offer far fewer benefits.
The best products for this purpose are often referred to as masthead amplifiers. These can give excellent results compared to set-back boosters as they amplify the signal at the aerial before the coaxial cable feeder losses take effect.
This DIY self-help guide gives detailed advice on choosing and installing masthead signal boosters as well as fitting distribution amplifiers for distributing Freeview or Sky TV around your home. If you are planning to install a loft distribution amplifier (loft box) our loftbox installation tips will prove useful.
If Freeview reception is poor on your indoor aerial, we recommend that you read our tips on choosing and installing a loft TV aerial before you buy a Freeview signal booster. This advice will help you to improve Freeview reception by accurately aligning and positioning your digital TV aerial, rather than unnecessarily fitting signal boosters.
By choosing and installing the best TV aerial, aligning it accurately and fitting low loss PF100 Coaxial Cable, you'll often achieve better Freeview reception than by installing aerial amplifiers (signal boosters) onto an existing poor aerial installation. Old aerials in particular are often fitted with lossy, inferior quality coaxial cable which may have suffered weather damage and water ingression. Fitting an aerial amplifier or signal booster to such installations is quite pointless.
If, after improving your TV aerial installation and realigning your aerial, you still get poor Freeview reception then a signal booster may help, particularly if you have a long coaxial cable down lead.
If you're using an indoor loft TV aerial, or the coaxial cable from a roof mounted aerial enters your loft before being fed downstairs, consider fitting the signal booster inside your loft. Fit the amplifier about 1 - 2 metres from the aerial for best results. However, as a general rule, only fit a digital TV compatible aerial amplifier if upgrading your existing aerial or re-aligning it failed to sufficiently improve Freeview reception.
Alternatively, if you have an external aerial on your roof, then a Masthead TV aerial amplifier fitted at the aerial will provide the greatest improvement and benefit for boosting Freeview reception, as it will amplify the UHF digital TV signal before any coaxial cable downlead loss is suffered.
The effectiveness of a TV aerial amplifiers is governed to a large extent by where they are installed and how well they are designed. A professional TV amplifier with a very low noise figure (< 3dB), moderate signal gain (10 to 15dB) and good strong signal handling will always significantly outperform a cheap booster.
This guide helps you to choose the best signal booster for Freeview DTT TV. If you currently suffer Freeview picture breakup or the picture freezing on one or more Freeview channel, then read on for more advice and technical help.
Contrary to some popular public opinion, a Freeview signal booster should only be used in poor digital TV reception areas of the UK. Signal boosters will not improve TV reception in strong signal areas, nor will they help reduce analogue TV picture ghosting. When an aerial amplifier is used in a good TV reception area it only serve to increase the likelihood of experiencing television interference (TVI) and will degrade overall reception quality. Such use often leads to annoying patterning on the UHF channels used for Sky TV, Freeview or a Video recorder.
Improve TV Reception
Bear in mind that a TV aerial amplifier fitted to a poor indoor aerial, is absolutely no substitute for fitting a high gain external digital TV compatible aerial. In fact a quality un-amplified roof top mounted aerial nearly always outperforms an amplified indoor TV aerial for Freeview and analogue reception and suffers much less interference!
It is extremely unwise to cascade two or more digital TV signal boosters (I.E. to use more than one Freeview signal booster chained together) as this can cause signal overload at the TV and lead to poor television interference immunity.
Despite our advice on the negative effects of cascading TV amplifiers, it is perfectly acceptable to fit a masthead amplifier at your TV aerial (powering it up the coaxial cable) and then to feed the RF output of your Sky+ box to a separate distribution amplifier (loft box), as these devices have just enough signal amplification to counter the coaxial cable losses of a typical TV aerial installation. In these circumstances, it is advisable to fit a masthead amplifier with no more than 10dB of gain to avoid interference problems.
The least effective type of digital TV signal booster is the cheap "set back" type which is fitted close to your television (pictured right). As the name suggests this type of TV aerial amplifier is connected at your television - between your television and the aerial face plate in your viewing room.
A set back Freeview signal booster will either have a 240V power supply or be powered by batteries. Since the UHF tuner inside a modern TV or Freeview Set Top Box is better designed and has a lower noise figure than a cheap signal booster, all set-back TV signal boosters really achieve is to amplify the noise and make Freeview reception worse! They also make your TV significantly more prone to interference from nearby radio transmitters like Tetra, Taxi bases and Amateur Radio enthusiasts.
In short, don't waste your money by buying a cheap TV aerial amplifier which you just intend to install in your living room behind your TV. You will find it ineffective and problematic. By far the best signal booster or amplifier is a masthead fitted type (described below).
Digital Coaxial Cable
By far the best Freeview signal booster is a fully screened digital TV compatible masthead aerial amplifier which should be installed close to the TV aerial, powered up the coaxial cable by means of a separate masthead power supply unit (included with the Wolsey amplifier) situated behind your main TV.
If you have an indoor TV aerial then the masthead amplifier should be fitted in the loft into the coaxial cable line, about 1 metre from the aerial. A masthead TV amplifier is usually powered up the coaxial cable from a separate mains power supply close to your TV.
Choosing the best TV signal booster depends largely on where you live and the strength of your Freeview DVB-T aerial signal. In general a medium gain aerial amplifier with a gain of about 10 - 15dB and a maximum noise figure of 3dB is a good choice. Our advice is to avoid buying a high gain TV signal booster as these increase the risk of suffering television interference problems (TVI) and TV signal overload which can make reception worse. If you suffer TVI from Tetra masts or other sources and have an aerial amplifier fitted, please refer to our TV interference tips page for advice.
More expensive types of Freeview compatible digital TV aerial amplifier sometimes incorporate advanced GaAsFet devices which benefit from high gain and very low noise as well as having excellent interference rejection. GaAsFet masthead amplifiers can really help boost extreme fringe area Freeview reception and solve DTT reception problems. This type of signal amplifier is ideal where Freeview picture breakup or freezing is experienced.
Masthead TV amplifiers (masthead digital TV signal boosters) can significantly improve Freeview reception in weak signal areas, giving far more improvement than a set back TV signal booster. The reason for this is a masthead amplifier amplifies the UHF digital TV signal right at your aerial, before any signal is lost by the coaxial cable downlead. This improves the all-important signal-to-noise ratio of your aerial system and boosts digital TV reception in weak signal areas.
Even if your Freeview TV aerial is external - mounted on your roof, the coaxial cable may enter your loft or run down the external wall of your house. Hence it may still be possible to carry out a DIY installation of a masthead aerial amplifier by connecting it as close as possible to your TV aerial, even if you can't physically get onto your roof to mount it right on your TV aerial mast. The closer the unit is mounted to the aerial (using the shortest length of coaxial cable) the more effective it will be at improving Freeview digital terrestrial TV reception.
Available with 4, 6 or 8 outputs the popular Slx distribution amplifier (pictured left) is suitable for boosting and distributing both Freeview digital TV and Sky around your home.
When used as a Sky TV distribution amplifier it is not fitted into the TV aerial feed, but fed by coaxial cable from the 2nd RF outlet on the rear panel of the Sky box.
The amplifier usually gets its 12V DC power from the Sky Digibox itself and is often mounted in the loft of a house from where it feeds a UHF signal to each TV in the house.
An installer menu option exists in the Sky box in order to turn on the power feed to a distribution amp. The Sky installer menu enables this function, which is essential to make the system work.
The Slx distribution amplifier is compatible with a Sky TV remote extender (Slx TV Link) often referred to as a 'magic eye' or 'remote extender'.
This allows you to change Sky TV channels in any room of your house by using a standard Sky remote control. Previous distribution amplifiers prevented the Sky TV link remote extender from working by blocking the infra red command signal from the Sky box to the Slx TV link remote eye (extender).
The latest generation of SLx distribution amplifiers solve these problems, and feed up to 8 TV's.
The loft box also acts as an aerial amplifier, providing a small amount of UHF signal gain to each TV to help counteract coaxial cable losses. Used in conjunction with the SLx TV link - Magic Eye IR Extender, this provides a cheap Sky TV distribution system with the convenience of being able to change Sky channels from any 'magic eye' equipped room.
Please note that you will need to buy one Slx TV Link for each room and will also need the following accessories when installing the distribution amplifier (unless you buy the kit above):
It is also worth noting that Philex offer a 4 Room Digital TV Distribution Kit with Digital by-pass (when available) which contains everything you need to distribute Sky TV and Freeview to 4 rooms. This includes the loft box and all TV link accessories. The kit does not include addition Sky+ remote controls, so if you need these they must be ordered separately.
We welcome your suggestions to improve the content of this signal booster page. Please use to send us your own tips regarding Freeview signal boosters or masthead aerial amplifier installation. However, we are unable to answer questions due to time constraints.
About The Author
Written by Steve Larkins.