The work is complex and services will continue to be transmitted at reduced power for a further period. We do not as yet have a date when services will to revert to full power. Please keep checking back to our website for further updates. Platforms affected include Freeview. Viewers may have difficulty with reception, however they can still watch their favourite programmes by using BBC iPlayer.
The government set a target of switching off FM radio services after a set of criteria on digital radio listening had been met. The criteria has recently been met but as yet the government have not undertaken a review of FM radio nor given any indication of when or if FM switch off will happen. This normally happens in the summer months, due to high pressure weather conditions in the atmosphere, allowing radio signals to travel further. The cause is an atmospheric effect known as Sporadic-E and can last from a few seconds up to an hour or more.
For more information on how weather can affect your Radio services, please see our guide. At night medium wave radio signals can travel much further than during the day. This means your radio is able to receive more radio channels either using the same frequency as the service you are listening to or adjacent to that frequency. The result is a higher level of interference and a deterioration in both the sound and coverage.
B asic Installation. It is important to check your installation is working properly and that your radio is in the best possible position. We have a basic installation guide to help you with this. Works and warnings. Check whether there are any known works or warnings that may be causing the problem.
Transmitter faults and frequencies. Use our Transmitter Checker to check the transmitter is not undergoing any work and to see which FM radio services you can receive from your location. Hi-Fi radios. If you are using a Hi-Fi tuner and stereo reception is hissy, but mono is fine, your aerial may not be powerful enough. You may need to consider a loft or external aerial to solve your reception problem.
FM radio signals can be affected by fine weather including high pressure and the only solution is to wait for the weather to change, you should not re-tune during this time. Our information on how clear skies and fine weather can affect your radio reception may be useful, please see our Weather Guide.
Pirate Radio. In some urban areas Pirate Radio can be a problem. Distorted S and Z sounds sibilance. This can happen when your radio receives more than one signal. The second signal is picked up by the radio moments after the first. For example you receive one signal directly from the transmitter and another is being reflected off a nearby hill. Try moving the radio or tuning to a different frequency.
Twittering and whistling. This often sounds like birds tweeting and happens if there is another frequency being transmitted near the one you are listening to. This can commonly be caused by high pressure when, during fine weather, radio signals can travel much further than normal.
These signals can be both UK and foreign stations. There is nothing that can be done and the problem will go away when the weather changes. Hissing and fading. This normally means that the signal you are receiving is not strong enough. See our guide on Hissing and Fading. Buzzing, clicking and pops. This may mean an electrical item in your home or nearby, is interfering with the reception of your FM radio and is causing the buzzing, clicking or pops you can hear.
See our guide on Buzzing and Clicking. Distortion - fuzzy, gritty, scratchy sound. This is commonly caused by the FM signals being bounced off objects or hillsides and reaching your radio by different paths. Its technical name is multipath distortion. It is often worst in hilly or heavily built-up areas. Indoor portables are especially susceptible. Distorted sound can also occur if your radio is off-tune. This can increasingly happen if your batteries are beginning to fail.
Ensure your radio is correctly tuned-in, and check that your batteries are in good condition, or use mains power. If you are hearing a hum it is often linked to an issue with your mains adapter.
You may need to check that all parts of your receiving system are fully earthed. The telescopic aerial fitted to stereo portables is a compromise and the radio will often only give really good results if connected to an external aerial. Some sets do this automatically. Make sure you are tuned to the best frequency for your area, as you can often pick up more than one signal.
Use our Transmitter Checker to find the best frequencies for your location. The CAI Confederation of Aerial Industries is a recognised trade body which can put you in touch with one of its members in your area. It is important to check your installation is working properly and that your radio is in the best possible location.
We have a basic installation guide you can read. AM reception can vary a great deal from day to night because of differences in the atmosphere. You may get good, clear reception during the day, but after sunset the signal may fade or become distorted.
This is why you can often hear radio stations from outside the UK at night. This is causing the buzzing, clicking or pops sounds you can hear. If you are still having problems see our sister site RTIS for further information. Effect of Weather on Reception. Weather-related problems tend to happen mainly in the summer, when high pressure can cause a radio signal to travel further than it would normally. If this distant radio signal is on the same frequency as the one you are listening to it can cause a reception problem.
This is because your radio will struggle decoding two radio stations on the same frequency. This is known as co-channel interference. The effect can last from a few hours to a few days and can cause intermittent effects on the service during that time. The effect that causes radio signals to travel further than normal is known as tropospheric ducting. For more information see our guide on tropospheric ducting. What to do:. There is nothing that can be done but to wait until the weather changes.
We have no control over it. If your problem is due to the weather, it should go away once the weather changes. Check our works and warning page to see if there any current weather problems. The most common FM radio aerial on a portable radio is a telescopic one. To get the best reception extend the aerial fully and move the aerial and radio around until you get the best reception. If using a hi-fi with a wire aerial, again extend as much as possible to get the best signal.
External aerials are also available for FM radio and will significantly improve reception. The aerial and cables need to be well maintained and you will need a radio that has an option to connect an external aerial. A radio which can tune to medium and long wave services usually has an aerial built in, which you cannot see.
As the aerial is directional, by simply turning the radio you will be able to get the best reception. AM does not use the telescopic aerial. This needs to be rotated to find the best signal. External aerials are also available for DAB and will significantly improve reception. The aerial and cables need to be well maintained and you need a radio with the option to connect an external aerial. Unlike the other services, all the predictions of DAB coverage are for indoor coverage.
Fading and Hissing. If you normally can receive a service, but you are now finding it is fading, or you can hear hissing, this could be down to one of three things. The first is a fault with the local FM transmitter. If not, then you will need to check the radio and aerial to confirm they are both working properly.
However, if you are using a frequency you have preset and there is no radio service on that frequency in your location, then the RDS may not work. At that point you will need to tune your radio until you find a signal.
If you are having continuous reception problems check your car aerial for damage. If you have an extendable aerial make sure it is fully extended to give the best possible reception. Local Radio Travel News. The RDS system is set up to detect local radio travel news. The way to turn traffic announcements on and off on varies between radios. Check you car manual for yours. Electrical Interference. Interference to MW or LW reception in a car can sometimes happen when the engine is running.
This can be due to various things including poor earth connectors, faulty or corroded HT leads and uncompressed spark plugs.
This can cause whining on the radio, which rises and falls with engine speed. It has also been known for the engine management system EMS to cause problems. The simplest test is to turn off your engine and see whether it goes away.
The buzzing and clicking lasts from a few seconds to a minute at a time. Switch off heating systems and see whether the problem goes away. If the problem persists when you turn the heating system back on, the problem could be with the thermostat, which may need to be repaired or replaced.
To find out if a particular switch is causing the problem, try turning the lights off one at a time. Many people are now using low power LED lights instead of the more traditional varieties. However, if the original light used a transformer rather than directly running off the mains, it is possible the transformer is causing the interference. This is because the transformer would have been designed to operate at the higher power and not the lower power the LED lights use.
Satellite TV provides a strong digital signal to subscribers' television sets and is almost completely wireless.
Earlier systems used very large dish receivers in order to focus the distant signals onto a powered antenna. Since different television channels were located on different communication satellites, these dishes would have to physically turn to predetermined points in the sky in order to receive the proper signals. Because regulation of these early dishes was not uniform, illegal electronic descramblers became a lucrative underground market. Stiffer penalties for unauthorized descramblers paved the way for legitimate satellite TV subscription services.
Modern satellite TV services have streamlined the process. A single communication satellite now remains in a steady orbit above the Earth, allowing all subscribers to mount a much smaller dish receiver at a fixed point. To get a perfectly clear signal like you find on cable, you have to be pretty close to the broadcast antenna without too many obstacles in the way.
The Satellite TV Solution Satellite TV solves the problems of range and distortion by transmitting broadcast signals from satellites orbiting the Earth. Since satellites are high in the sky, there are a lot more customers in the line of sight. Satellite TV systems transmit and receive radio signals using specialized antennas called satellite dishes. Early satellite TV viewers were explorers of sorts. The dish and receiving equipment gave viewers the tools to pick up foreign stations, live feeds between different broadcast stations, NASA activities and a lot of other stuff transmitted using satellites.
The provider selects programs and broadcasts them to subscribers as a set package. Early satellite television was broadcast in C-band radio — radio in the 3. Digital broadcast satellite transmits programming in the Ku frequency range There are five major components involved in a direct to home DTH or direct broadcasting DBS satellite system: the programming source, the broadcast center, the satellite, the satellite dish and the receiver.
Most of the turnaround channels also provide programming for cable TV, and the local channels typically broadcast their programming over the airwaves. Satellite TV helps deliver signals in areas where customers may not be served by cable television or "terrestrial" broadcasting.
Satellite TV generally uses two different frequency sets to deliver signals. One is the Ku band, a dedicated channel for satellite TV communications. Other analog "big dish" systems use the lower C band, which is also used for certain other kinds of technologies. Although the Ku band is the dedicated channel for satellite TV, the C band can help signals withstand some interruptions, such as signal disruption from inclement weather.
By: Justin Stoltzfus Contributor, Reviewer. By: Satish Balakrishnan.
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