Rogues Gallery

Every downlead should be bonded to earth using 4mm csa cable. There should be an earth rail or a row of earth tags, with a fat green/yellow cable bolted to it. In fact there isn’t even a normal earth via the mains plug. The whole structure of the system is free to take up whatever voltage is applied to it. Many aerials and all LNBs do not connect the coaxial braid to the fixing brackets, and so the is no chance that they will provide a path to earth. A faulty TV set or satellite receiver in any dwelling could put mains voltage onto every outlet plate in the building.

Imagine poor old Jerry Attrick, 89 years old, champion bowls player (1992), and scared of lightning. As the storm approaches he quavers over to the TV socket and creakily kneels down to unplug the flylead, leaning heavily on the radiator with his sweaty palm as he does so. He touches the aluminium coax plug and receives a fatal electric shock. Ten flats away old Mrs Crumble sleeps easily in her bed, unaware that the TV amplifier her son got from a stall on the market so she could have a telly in the kitchen has developed a fault. The fault doesn’t affect her TV reception but it does put 230V AC at up to 300mA onto the incoming aerial lead.

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