Roger asked about polarisation. All main analogue TV transmitters are horizontal polarisation. This means the director elements of the aerial need to be parallel to the ground. In very hilly areas where lots of repeater stations are used to get the signal into valleys, the repeaters always use vertical polarisation as if gives extra separation between the level of the repeated signal and that of the source signal it has repeated. If you are moving around the country along canals that are sometimes along a valley bottom then a cross polar antenna will work better in those places where a normal one doesn't. Alternatively put your normal antenna on a swivel mount so that you can rotate it into a vertical position if you cannot get a good signal.
Graham www.jannock.org.uk
