How many transponders for satellite

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. This has the potential to cause electrical interference. Street lamps. Street lamps can sometimes cause buzzing and crackling sounds on your FM radio.

Keeping a note of when each lamp comes on and goes off will help to identify whether this is the cause of your interference. If it is, contact your local council. Passing traffic. A faulty or uncompressed engine can cause a distinct buzzing 'whine' which varies with engine speed - motorcycles tend to be the worst. Try to move your radio away from the street or use an external aerial.

Electric motor. An electric motor is used in many appliances such as electric lawnmowers, washing machines, drills and hairdryers etc. A faulty motor can cause electrical interference. Check any appliance with an electric motor by moving your radio away from it to see whether the sound improves.

If you have several appliances with electric motors you may need to turn them all off and try the above one at a time. With all of these potential causes, it is worth keeping a log for at least two weeks to determine whether there are any patterns or trends to the interference.

This can be due to:. Reduced transmitter power. Use our transmitter tool to see whether your local transmitter is currently affected by maintenance work. Stereo Signal. Try moving the radio to another position, such as near a window, higher up, or another room. If you get hiss when listening to a stereo signal try switching to mono. Stereo reception needs a stronger signal than mono. If you have a portable radio you will be able to pick up more of the receivable signal if your telescopic aerial is fully extended.

If you have an external or loft aerial check they are functioning correctly. Tuning to the wrong transmitter. Use our transmitter tool to check you are tuned to the best frequency for your area, as you can often pick up more than one signal. Very occasionally, the weather, usually high pressure, can result in a weakened signal. There is nothing anyone can do about this and the only answer is to wait for the weather to change. For more information see our guide on how weather can affect radio reception.

Help receiving TV and radio. Reception and interference main navigation Menu. Which transponders does the BBC use? Reception Problems If you have a reception problem with one service in a multiplex you will also have problems with all the other services in that multiplex. Check out our tools Use our problem assistant to help you diagnose problems with reception and interference View tool. Check the status of the transmitter you are using and find out TV and radio channels and frequencies View tool.

My DAB reception has started to drop out, is this due to poor reception? How can weather affect DAB reception? Tuning Most DAB radios can be tuned easily at the touch of a button. Telescopic aerials Telescopic aerials on portable radios should be fully extended to receive a good signal. Outdoor aerials An externally mounted aerial can be attached to many types of DAB portable radio and hi-fi systems. Cables and Connectors If you have an external aerial, a radio signal will always lose some of its strength as it passes along the cable and through the connectors.

Works and Warnings Check whether there are any known works or warnings that might be causing the problem. Tuning DAB uses multiplexes to group services together. External aerials It is important to check the cables and the aerial for damage and that they are operating correctly.

Damaged Cables Water can get into external cables and can cause reception problems. Car Radios Radio reception can drop out when on the move due to changes in topography. Weather Radio signals can be affected by fine weather including high pressure.

Lost reception of one or more station within a multiplex If all other stations are working ok and you have just lost one station. If your car radio is showing no signal or no service for a station you usually receive, this could be down to one of the following things: DAB Transmitter Fault If you know your location, you can use our transmitter checker to see whether there is a problem.

Interference Poor DAB reception can also be caused by equipment used in the vehicle. Topography When travelling in the car, your signal can be affected by natural features of the land, for example, hills, valleys, rivers, etc.

How to find these services It is best to re-tune your radio when they are broadcasting, so it will store the station in its memory. Checking for problems Check cables and leads within your property to ensure the problem is not a simple installation fault. Electrical interference There are differences between a reception problem and one caused by electrical interference. Why is this? My Television reception is usually good in the day, so why does my television reception sometimes deteriorate in the evenings?

Why are subtitles sometimes delayed or out of sync? Why am I receiving a voice commentary over my picture. What is this, and how can I turn this off? Freeview Help Guides What is a good Freeview installation? Aerials There are all kinds of aerials available on the market and some which are specific to certain frequencies. Internet Speed Test. Remote Control.

Business Technologist. Experience Information Technology conferences Join your peers for the unveiling of the latest insights at Gartner conferences. View Conferences. Gartner Webinars Expert insights and strategies to address your priorities and solve your most pressing challenges.

By broadcasting to orbital satellites, they are able to blanket large portions of a continent with a single signal. Most television satellites carry 24 to 56 transponders. Each transponder is capable of receiving, amplifying and broadcasting a compressed stream of data carrying multiple channels. Analog satellite systems can broadcast around 30 channels per transponder, while digital systems use compression techniques to carry up to channels on a single transponder.

Television transponders are designed to retransmit received signals at a different frequency than the uplink signal to avoid interference. The dish receiver that sits on top of the television customer's home is similar in many ways to "rabbit ear" television antennae. A communications satellite transponder is a series of small, chip-sized, interconnected circuits that form a communications channel between the receiving and transmitting antennas.

These circuits are integrated into satellites in order to provide bandwidth and power over designated radio frequencies. The transponder bandwidth and power determine the capacity of information that can be transmitted through the transponder and how big the ground equipment must be in order to receive the signal.

With data compression and multiplexing, several video and audio channels may travel through a single transponder on a single wideband carrier.