The alignment of your satellite dish is important especially if you are set up to receive UK TV channels via Astra28E. Since March 2013 new satellites have been operating at 28E and the technology of these new satellites is such that the signal is more accurately focused on the UK so that people in France and other parts of Europe now receive a much weaker signal on certain channels. The systems affected mostly lose BBC 1 & 2 and Channel 4 & 5.
Many things can affect the signal you receive:
- Dish alignment
- Dish distortion
- Dish size
- Water / corrosion
- LNB problems
- Receiver problems
Satellite dish alignment
The satellite dish alignment is critical to receiving a good, reliable signal. For this the support bracket / pole must be upright and the elevation, azimuth and skew angles must be correct. This can only be achieved by using a professional satellite meter for optimum signal strength and quality.
Elevation is the angle above the horizon and this varies relative to your location.
Azimuth is the compass bearing and in the case of Astra28E it is 28.2° East of South.
Skew is a rotation angle for the LNB to compensate for the curvature of the Earth.
Distortion of the dish can be caused by over zealous installation, high winds or flying debris etc. and causes the signal to be weakened.
As mentioned above, due to the renewal of ageing satellites the signals from some are now weaker in parts of Europe so whereas your existing dish was more than capable of delivering a reliable signal in the past you may now need to increase the size of your dish to compensate for the loss of signal strength.
Water / corrosion
If the cable is not of the correct type or is not correctly installed water damage and corrosion may result in no signal or a degraded signal to a point where in certain conditions picture break up will render the system unusable.
There are various grades of cable for indoor and outdoor use and of varying quality.
LNBs can develop faults due to age, corrosion due to moisture, etc.
Receivers vary in quality and the strength of the signal required for optimal system reliability. It may be that your previously reliable box cannot cope with the current signal strength or quality.
Trees and hedges grow so it may be that what was a clear line of sight to your desired satellite when it was installed is now interrupted by leaves and branches.