Its usually either the aerial/cable is faulty or more than likely the PSU. The PSU`s use the worst capacitors known to man. They ALWAYS fail after about 18 months causing all kinds of problems, failing to boot, pixellated picture, "no hard drive present", and so on. If the box is starting to play up, its probably the PSU. You can get them on Ebay, or get yours repaired by a tv engineer. Far cheaper than buying a new one.
thomson fan
June 2012
upgrade your TV Ariel am losing signal the box is telling you whats wrong ?
wirecutterman
January 2012
Automatic Answer
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howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix dtt receivers.