Reception Trouble

Initial checks of your equipment

  • Check that your mains plug is wired correctly with tight electrical connections, and that it is pushed firmly into the socket.
  • Check that you are able to get a good steady picture at the times when the reception problem is not present.
  • If any reception problems are apparent ask your neighbours if they have the same or similar type of problem.
  • If a new aerial has been installed, it may be wise to adjust the tuning of each channel manually on the TV, or rescan for digital channels via the appropriate menus on the set top digi box.
  • Check that your aerial lead appears to be in good condition, with its plug firmly attached to the lead and making good contact when pushed into the aerial socket on the back of the TV set or digi box.
  • Also check that the cable is of the best quality, copper braid with copper or aluminium foil type cables are generally a minimum requirement, especially for digital reception.
  • Ensure that there are no tight bends or kinks in the coax cable and also ensure that the cable is not routed close to any electrical cables or items such as thermostats or motors etc…

Digital TV Reception Problems

Poor Digital Reception (notice break-up at bottom of picture)

Very Poor Digital Reception (this could be due to weak signal or interference)

Unlike analogue reception problems where the various patterns tell us what the problem is, digital reception generally has the same screen output for all reception problems be it weak signal or radio interference. Usually, cures for analogue reception will also work for digital reception problems.

Essentials for Good Quality Digital Reception

Use a good quality benchmarked aerial (follow the aerial manufacturers cable route recommendations) or as a minimum, an aerial with a corner type reflector with fitted Balun.

Use good quality double-screened coaxial cable (preferably benchmarked types) and good quality connectors.

Avoid splitting the signal, use distribution amps if reception in more than one room is required.

Use masthead type amplification; avoid set back type amplification as the main method of distribution (the signal will have degraded by the time it reaches the set back, if it is not pre-amplified).

Take care when running the cables, avoid tight bends (kinks) and do not run the cable alongside any other cable, especially mains/electrical cables.

Keep cable connections and lengths to an absolute minimum; if possible take the cable through the wall and directly into the receiver rather than connecting via a wall plate. (If wall plates are to be used, use screened versions).

What you can do?

  • If the picture is breaking up constantly or no channels are found, the signal is too weak and will need attention, try the following:

  • Ensure that the aerial is benchmarked, or as a minimum, is the corner reflector type with a Balun fitted.
    • Check the aerial polarity (horizontal or vertical).
    • Ensure that the aerial is aligned to the transmitter.
    • Ensure that no obstructions are directly in front of the aerial, i.e. trees, chimneystack (or water tanks in loft installations).
      • If necessary increase the installed height of the aerial to avoid obstructions.
      • If loft mounting is unsuccessful, try installing the aerial outside as high as possible.
    • Check all cable connections and ensure that the cable is good quality double-screened type.
      • Ensure that interconnecting leads i.e. fly leads and Scart leads are good quality screened types.
    • Ensure that the aerial is of the correct group type i.e. A, B, CD or WB. (For example, if a group ‘A’ aerial is installed, digital channels within group ‘CD’ may break-up or may not be received at all).
    • If after everything has been checked, the signal is still weak, try a higher gain aerial and/or a pre-amplifier.
  • If the picture breaks up when an electrical switch is made, i.e. thermostat or light switch, the problem could be the shielding effectiveness of the coax cable.
  • If the cable is old, replace it with good quality double-screened cable (preferably benchmarked versions) on all cable routes.
  • Ensure that the cable is not running alongside other cables especially electrical cables.
  • If the picture breaks up intermittently with no electrical switching taking place, the cause could be radio interference i.e. Tetra or PMR (Private mobile Radio)
  • Again, use good quality double-screened cable (preferably benchmarked versions), again this includes interconnecting cables, i.e. fly leads and Scart leads.
    • Check all cable connections.
  • Try re-positioning the aerial to a position that could be shielded from potential interference but will still be able to receive the TV signal.
  • Install a Tetra filter or an amplifier with inbuilt Tetra filtering.
    • Inline passive filters and amplifiers are now available with Tetra filtering.
  • If after attempting all relevant cures the problem still exists, the problem could be the TV, especially if it is an old model (older models may not have the screening effectiveness as that which is found on modern units).
  • Check the wind or wildlife i.e. large birds (perching) have not moved your aerial. A glance at neighbouring aerials will generally show an approximation of the correct direction of the local transmitter.
  • Check that you have the right aerial for your area. If you are in doubt, consult your local dealer or aerial installer.
  • Hotels, blocks of flats and some housing estates use a communal aerial, which you cannot check yourself. You should contact the landlord or his nominated contractor.