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is a very impressive document. Good sound practical advice. I hope you don't mind a few suggestions.
De-typoed: Small set-top aerials vary in performance from poor to useless in most areas. In strong signal locations one may be ok for a portable TV. The advantages are minimal cost, no installation, and portability.
De-typoed: In practice roof mounting gives a much stronger and better quality signal than a loft aerial. A loft aerial will be quite satisfactory in many cases, but not always. Rooftop is of course less convenient and more expensive. Outdoor aerials, poles and cables have limited life, so the expense is repeated over time.
Error: Baluns Nearly all TV aerials are described by the manufacturer as 75 ohm aerials, yet nearly all are really designed as 300 ohm aerials, with construction details reducing this to some degree, but not to 75 ohm. Connecting a 300 ohm aerial to 75? cable causes loss of gain, tendency to reflections, and some degree of degradation of signal quality. Better aerials have a small balun inside that transforms the 300 ohm signal to a genuine 75 ohm feed. All CAI approved aerials have this.
In fact even cheap aerials are designed to match to 75ohm feeder. (More or less). A folded dipole with no parasitic elements would match to 300 ohm. Once you start adding elements the characteristic impedence drops. The balun (in this case) usually converts 75 ohm balanced to 75 ohm unbalanced. However some manufacturers use the balun design to tweak the matching, so the dipole terminals might not be quite 75 ohm. The old baluns for VHF FM actually did convert 75 to 300 or vice versa, as well as converting balanced to unbalanced.
De-typoed: a.. Don't choose a position where it will have your eye out every time you climb through the loft hatch! De-typoed: a.. If more than one location is available, do a survey at each position to see which is best. The easiest chimney to get to might not offer the best results! De-typoed: Height is important - raising an aerial as little as a metre De-typoed: If multipath (i.e. ghosting) is a problem, try a more directional aerial, and try different bearings. It may be preferable
Bill