Self Help Topics

• TV & Radio Interference
  • TV Interference (TVI)
  • Scart Cable Interference
  • Computer RFI
• TV Servicing Tips
  • Grey Scale Alignment
• UK DAB Radio
  • Improve DAB Reception
  • London DAB Radio
  • Pure Evoke 2S Review

 

Improving Freeview Reception

This self-help guide provides advice on how to improve TV reception and install loft TV aerials for best results. Included are troubleshooting tips to solve common Freeview reception problems, as well as help to diagnose faults and set top box installation issues, like missing Freeview channels.

Guidance is also offered on how to improve your existing TV aerial installation and when to use a Freeview signal booster to get the best reception.

Freeview Coverage: UK Post Code Check

Approximately 98.5% of the population can receive Freeview via their TV aerial. Freeview aerial requirements vary by region depending on transmitter frequencies used. You can check Freeview coverage in your area and find out whether you need an aerial upgrade, by entering your postcode at the Freeview Website. Useful digital terrestrial TV coverage maps and predictions are also available by entering your postcode at the Wolfbane Website.

Before buying an TV with integrated Freeview or a set top box, be sure to check the likelihood of getting reliable reception using the postcode checker above. The digital TV postcode check errs on the side of caution, so many fringe areas which still have poor digital terrestrial TV coverage, may be able to get reasonable DTT reception if an external high gain aerial is used.

Freeview Television Channels

There are around 51 free terrestrial digital TV channels broadcast free to air (FTA) on Freeview, together with up to 12 HD channels. Additional channels are available for an optional monthly subscription payment and require a compatible TV or set top box.

For those unfamiliar with the Freeview TV service, here is an up to date Freeview channel list of all free to view television channels and a list of Freeview digital radio stations. The official site also provides a handy Freeview channel guide in PDF format.

Problems with Low Cost Digital TV Adaptors

Cheap Freeview receivers are now available under £40 which include a UHF modulator - making them suitable to convert any TV to digital - even an old TV set without a Scart connector.

However, if you buy the cheapest Freeview box you can find in a local supermarket, it probably won't have a built-in UHF modulator and will be a relatively unknown brand. Cheaper Freeview boxes can suffer poor Freeview reception in weak signal areas, including picture breakup problems and freezes due to low quality components and poor design. This can lead to much worse susceptibility to impulse noise interference from electrical appliances.

Whilst a log periodic TV aerial can help reduce this type of impulse interference, it still pays to spend a little more to get a higher specification set top box with improved interference immunity and better poor signal performance.

Most budget Freeview boxes must be connected to a TV using a Scart cable, as they produce no modulated RF Output signal via the 'UHF loop through' sockets.

Distribution of digital terrestrial TV channels from a cheap Freeview receiver is then only possible by purchasing a RF Modulator from Amazon. The Modulator provides a programmable RF output on UHF Ch21 - Ch68 which will feed a separate TV distribution amplifier to distribute Freeview TV around the home to other rooms. Just connect the Modulator to an unused Scart output on the Freeview receiver or set top box and use the Modulator's RF output to feed a Loft Distribution Amplifier.

If your TV is old and hasn't got a Scart connector, the Modulator can also be used to add Freeview services via your UHF aerial feeder. Just connect your aerial to the input of the modulator and its RF output to your TV, then connect the Modulator to the TV Scart output of your Freeview receiver or budget set top box using a Scart cable - job done!

Compatibility with Old 4:3 TV's

The UK Freeview service is fully compatible with old 4:3 aspect ratio televisions. Most set top boxes support TV aspect ratio settings of 16:9, 14:9 pan scan (compromise), 16:9 letterbox and 4:3. The TV aspect ratio setting is set during set top box installation by on-screen menus, which are provided even on cheap Freeview receivers. However, for best results the use of a 16:9 widescreen television is preferable as most UK digital TV channels now transmit their programming in 16:9 format.

The disadvantage of using a 4:3 TV with Freeview or Sky digital TV are considerable. Viewing must either be made in 16:9 letterbox mode (with black margins above and below the picture) or alternatively, in 4:3 picture mode where the picture is adapted to fill the 4:3 screen, resulting in about 20% of the sides of the picture being cut off. This can result in screen captions and words being cut off at the edges of the screen.

Freeview TV Distribution Amplifiers

If you wish to use a Loft Box Distribution Amplifier to distribute Freeview digital TV to other televisions around your home, make sure you buy a Freeview receiver which has a built in "UHF modulator". The UHF signal generated by the Freeview receiver's UHF modulator provides Freeview channels on a selectable UHF TV channel and this can then be feed a TV distribution amplifier. To avoid interference to existing analogue TV channels, a video recorder or Sky Digibox, it is important to set the Freeview receiver UHF modulator to an unused UHF channel in your area. For troubleshooting help read our Digital TV Retuning article.

How to Install Freeview Receivers

When installing Freeview receivers, the aerial connection of the receiver ("ANT. IN") should be connected directly to your TV aerial, which must be capable of receiving all of the digital terrestrial TV channels (DVB-T multiplexes) broadcast in your area.

To get the best results, the Freeview receiver should be the first RF loop through device in any chain of equipment. This ensures that the Freeview digibox gets the best signal quality (avoiding interference or added noise from other peripherals like video recorders or a Sky box). Click here for a picture showing typical Freeview set top box aerial in/out connections. The unit shown is a cheap Freeview box by Matsui.

Solving Freeview Installation Problems

In some UK regions, the DVB-T terrestrial digital television signal from more than one Freeview transmitter or region may be received. This can cause reception problems as the box will try to install the digital TV channels from both regions, even if the signal quality is low. The only way around this is to note the UHF DVB-T multiplex (mux) channel numbers for your preferred DTT transmitter and install them manually.

Start by deleting all installed channels by invoking a new Freeview installation (channel re-install) with the aerial cable disconnected. When complete a 'no channels found' warning message will be displayed. Then carry out a full manual installation for each of the DVB-T UHF multiplex channel numbers for your region (there are 6 DTT muxes currently transmitted in the UK). These are BBCA, BBCB (HD), D3+4, SDN, ArqA and ArqB - each of which has a separate UHF channel number.

Most Freeview boxes provide a manual installation option whereby the individual UHF channels of each DTT multiplex can be manually entered using the handset and all free to air digital TV channels found stored into the EPG. Each UHF DTT mux channel for your region should be entered in turn and all of the channels found saved to the EPG.

Manual Freeview channel installation avoids installing the multiplexes from out of area DTT transmitters. Find the UHF mux channel numbers for your UK DVB-T transmitter by clicking here.

Freeview TV Aerial Upgrades

In some UK areas a Wideband Aerial Upgrade (see Triax 52 - right) may be needed to receive Freeview digital terrestrial TV. This is because the digital multiplexes in some regions are broadcast on widely split UHF frequencies, requiring the use of a wideband aerial.

If you have an older TV aerial, it is possible that the type of aerial fitted was designed just to receive a narrow group of legacy analogue TV channels. Such an aerial will give poor reception (at best) if the digital TV channels in your area are outside the frequencies that the existing aerial was designed to receive.

Use the Freeview Post Code Search utility to check the need for an aerial upgrade in your area.

Using Existing Aerials for Freeview Reception

In London all digital TV services from the Crystal Palace transmitter are in same UHF aerial group (I.E. on similar frequencies) to those which used to transmit analogue terrestrial television. Therefore, an existing Crystal Palace Group A TV aerial in a good state of repair may suffice for receiving all DTT Freeview channels in London. If you require a new aerial for Crystal Palace reception, we recommend a Blake DMX10A TV Aerial for Group A Frequencies, which will give far better results than a wideband aerial.

Viewers watching the Caradon Hill transmitter (Cornwall), will also find the Blake DMX10A aerial gives much improved reception over a wideband aerial.

The same will apply in other UK regions where the DVB-T multiplexes are within the same frequency range as existing analogue TV services.

Loft Freeview Aerials

Loft installed Freeview aerials can be suitable for DTT reception in strong signal areas close to the transmitter. There is usually a signal loss of about 30% by mounting a UHF aerial in the loft. Losses are greater for the higher UHF channel numbers (closer to Ch68).

Having an indoor aerial inside your loft means that it is more prone to picking up electrical interference from appliances inthe home including domestic central heating, hot water thermostats and light switches. If you get momentary loss of picture (picture freezing) problems on your Freeview digibox, consider upgrading to an outside aerial fitted by a professional CAI member TV aerial company.

When installing loft aerials for Freeview television, check the signal quality on all channels to ensure all digital multiplexes are being received at roughly the same signal quality. If reception of one DTT multiplex shows much lower signal quality, move the aerial slightly to compensate.

Freeview Reception in Poor Signal Areas

Where Freeview reception problems are experienced in poor signal areas for terrestrial digital TV, check your aerial and coaxial cable feeder is double screened to reduce signal loss. See aerial recommendations to identify the type of aerial you will need for your particular region, in order to get the best Freeview reception in weak signal areas.

Of course, there are never any guarantees that fringe area Freeview reception will be possible, but a good roof top aerial will really help. The aerial should be mounted above roof height and accurately aligned using a signal meter by a professional aerial company. A 1 degree up-tilt on the mounting of the aerial may provide some further signal benefit for fringe reception, especially if you live in a valley or a nearby hill obstructs reception.

Signal Boosters & Mast-Head TV Aerial Amplifiers

Using a Freeview signal booster will reduce your TV's immunity to interference. Avoid using them unless absolutely necessary. Using a signal booster with a poor aerial is absolutely no substitute for fitting a good quality, roof mounted digital compatible TV aerial without an amplifier.

If you need to use a Signal Booster to improve your Freeview reception, it should be a Fully Screened Masthead TV Amplifier compatible with digital terrestrial TV and be mounted close to the aerial (at the mast-head). Older Un-screened Masthead Amplifiers are far more prone to interference.

Note:
High gain aerial amplifiers can make your TV prone to interference (TVI) from nearby radio transmitters such as police Tetra masts, taxi bases and amateur radio stations. Where such interference is observed, the aforementioned services are often not to blame. The interference is frequently the result of poor aerial amplifier design leading to signal overload. In these cases fitting a filter between the aerial and the amplifier (at the mast head) usually eliminates the problem. Fitting TVI filters at the TV is unlikely to help resolve any interference problems if an aerial amplifier is fitted at your TV aerial. More troubleshooting advice is provided in our TVI Filters article.

One For All Freeview Aerials

One for All indoor set top aerials can be used for Freeview reception in strong signal areas, but interference problems can be an issue and in our set top aerial tests they weren't the best choice for Freeview DTT reception. Read our One For All Aerial Reviews for more information. We recommend the Telecam TCE2001 set top aerial as being one of the best available.

Coaxial Cable

To get the best Freeview TV reception we recommend using double screened satellite grade coaxial cable from your digital TV aerial like PF100 Digital TV/Satelllite Cable which has a foil copper screen in addition to stranded copper screening and a low loss foam dielectric. This type of cable replaces the CT100 and CT125 which had an air spaced dielectric and was more prone to water ingression.

It may be helpful to read some tips on identifying good versus bad coaxial cables to identify whether upgrading your coaxial cable would be worthwhile. If your television aerial was installed a few years ago, there is a strong likelihood that the coaxial cable used is only single screened and therefore unsuitable for digital TV.

If you have pre-wired TV sockets in your rooms that were fitted when the house was built, it's worthwhile inspecting them, especially if your Freeview picture is breaking up regularly. Make sure all TV socket face plates are correctly wired and use double screened coaxial cable and that the screen of the coaxial cable is anchored to the faceplate earth. If your TV points use older single-screened coaxial cable and Freeview reception problems are encountered, you may need to replace the coaxial cable to your aerial with Satellite Grade Coax Cable. Double screened coaxial cable installation to your aerial will improve the analogue TV picture too as it has much lower signal loss at UHF TV frequencies.

The extra screening provided in modern satellite cable greatly reduces noise or interference pickup along the cable which can otherwise result in DTT reception problems causing picture breakup, pixelation and frozen images on your Freeview set top box or IDTV.

Checking Freeview Signal Quality

Nearly all Freeview receivers provide an on-screen method of checking signal quality and signal strength. Digital terrestrial TV signal quality is the most important of these parameters as very low signal quality reading will mean that your Freeview receiver will be much more prone to domestic or outside interference leading to picture freezing, pixelation, break up and dropouts. Click here for an example Freeview signal quality screen taken from a Humax PVR8000T digital TV receiver.

What is Digital TV Signal Quality?

The Signal Quality indicated by any Integrated Freeview TV (IDTV) or Set Top Box is based on Bit Error Rate measurement (BER) at the receiver. The Standard Definition Freeview DVB-T service utilises MPEG2 compression technology, whereas Freeview HD utilises the more efficient MPEG4 standard.

In common with all digital broadcast standards, both MPEG2 and MPEG4 have built in Error Correction which effectively corrects all bit errors up to a certain point - known as the 'Digital Threshold' - which represents the cut-off point of reliable reception.

When the quantity of bit errors encountered exceed the capabilities of the DVB-T error correction system to correct them, the Freeview picture will break up, suffer significant additional pixilation or disappear altogether with a 'No Signal' or 'Poor Signal' message.

The 'Digital Threshold' of any receiver will be different depending on the tuner design, with the best set top boxes from Humax performing much better under poor signal conditions close to the 'Digital Threshold', when compared to cheap Freeview receivers which frequently have poor tuners and greater susceptibility to interference.

The Signal Quality reading of any set top box will be influenced by:

*This is one reason why using set-back amplifiers (boosters) is such a bad idea as they do little to improve overall signal to noise ratio. Masthead amplifiers, by contrast offer much more signal quality improvement.

Solving Freeview Television Reception Problems

Freeview television can be prone to electrical interference which can lead to the digital TV picture freezing, with momentary pixelation or total break up. Electrical interference problems will always be worse on a loft aerial. Read the notes below to check your digital TV installation for common faults. Further information on these topics is available on our TV Interference and Loft Aerial Installation articles.

Missing Freeview Channels

One very common problem with Freeview digital terrestrial television is missing channels. This is nearly always due to one or more "DVB-T digital multiplexes" being received at a poor signal level, below that of the Freeview receiver signal threshold. 6 UHF digital multiplex channels are currently transmitted in the UK with each DVB-T mux transmitting a group of digital terrestrial TV channels.

Adding New Freeview Channels

It is not necessary to find out the UHF channel number or the frequencies of digital multiplexes transmitting new Freeview TV channels in order to add them to your EPG channel line up. All Freeview receivers provide an "add channels" facility in their DTT installation menu. Either "add channels" or do a re-installation of your Freeview box to find and install new DVB-T terrestrial digital TV channels. They will then automatically appear in the Electronic Programme Guide (EPG) of your receiver. Click here for help.

Recent Changes to Freeview Channel Numbers

The EPG channel numbers of some Freeview channels changed in 2013. It may be necessary to do a re-installation of your Freeview box to update your EPG channel line-up. This can be done by carrying out a "new installation" (from the Installer menu of your set top box or TV). If you receive signals from more than one transmitter, manual installation is advised to avoid installing the wrong regional TV services.

Freeview Signal Loss in Bad Weather

If a property is surrounded by tall trees or where multi-path reception is experienced, it is not uncommon for Freeview signal quality to go up and down as the trees or aerial move in high winds. Wet leaves attenuate UHF DVB-T multiplex signals even more. If you get a poor Freeview TV signal and have tall trees directly in line to the transmitter, you may get problems with reception dropout under adverse weather conditions. Trees can attenuate the DTT signal considerably especially when leaves are wet. It will help if you:-

Aerial Down-Lead Troubleshooting

Where Freeview TV interference, pixelation or picture breakup is experienced, always check the quality and condition of the coaxial cable used as a downlead from your aerial. Any cable joins should be visually checked (see "Joining Coaxial Cables" below). To get the best DTT reception, double screened coaxial cable should be used. The cable junction box of an old, badly weathered TV aerial could be letting in rainwater if mounted externally, so always check aerial coaxial cables for signs of water ingression or copper corrosion if your Freeview picture is breaking up.

Joining Coaxial Cables

Badly joined coaxial cables can result in serious Freeview signal loss. The only acceptable method of joining TV coaxial cables is by using two F type plugs and an F Type coupler, with self amalgamating tape to weather proof the joint. To apply, stretch the amalgamating tape to about twice its length and wrap the whole assembly.

We offer step by step help fitting F type plugs. The prepared connectors are then connected together using the F-type female to female adaptor with an example joint.

Faulty TV Plugs and Faceplate Sockets

Check the wiring of all coaxial plugs from the aerial to your Freeview receiver to ensure that they are properly fitted on all peripherals and at the TV itself. See how to fit Belling Lee type TV plugs for help.

Also check the TV socket faceplate wiring in all rooms for poor installation too, especially in new houses where workmanship can be poor. The screen of the coaxial cable must be corrected connected to the shield (earth) of the TV faceplate socket and the cable terminated in a tidy fashion.

Digital TV Interconnect Cables

The output of the DTT Freeview receiver loop through (TV OUT) should be connected to any Sky Digibox and/or video recorder before being connected to the TV set. The coaxial cables used for interconnecting all TV peripherals must be double screened, to avoid interference pickup. Set top boxes (STB's) all contain on-board computers which radiate RF noise from the set top box itself. If poor quality coaxial cable is used to interconnect set top boxes, this noise will be picked up by the cables, giving rise to interference on both terrestrial digital TV signals and Sky TV output, seriously degrading picture quality.

In particular, budget Freeview boxes often have unscreened plastic cases and interference radiation can be a serious problem unless precautions are taken.

Many coaxial cables provided with Freeview set top boxes are of poor quality, having inadequate screening, leading to interference pickup problems. Try to avoid using a thin, single screened, poor quality coaxial interconnect cable. These single screened coaxial cables are unsuitable for Freeview digital terrestrial TV installations. Poor quality coaxial cable being used to interconnect peripherals like a Sky Digibox or Freeview receiver is another common cause of DVB-T interference pickup and poor picture quality.

If you intend using these low quality interconnects permanently, bunch the cables up using cable ties and keep the bunches away from mains cables, the Freeview receiver and Sky Digibox as far as possible. If in doubt, you can make up your own interconnects cut to length using double screened satellite coaxial cable, or have a TV engineer make up some cables to this specification.

Tip: Always use double screened coaxial cable for interconnecting your digital TV set top box, Sky+ HD box and TV.

Help Us Improve

This article aims to provide advice on Freeview aerials and expert troubleshooting tips for fault finding common Freeview reception and aerial problems which result in picture break up. Please to suggest improvements to this page.

The UK digital terrestrial TV service (Freeview DVB-T) is being extended and the power increased in order to prepare for digital switchover, so reception will improve at all locations, even those currently getting poor reception.

Written by Steve Larkins.