At the risk of sounding like a bit of an orienteering virgin, can you
explain how to do that with a compass (which I don't have, but I
expect they're dirt cheap, the simple ones). Do you mean that I should
somehow position myself in the road and orientate with the compass
accordingly? I can't get close to the house in question because of
fences, but I can see the aerial through my binoculars in much detail!

Thanks! (And thanks, too, to Frank earlier.)

NB: Other houses in the road also have their aerials pointed "pretty
much" in the same direction, but the emphasis here is on "pretty
much", because I wouldn't say their installers had bothered on
position too much, going by the discrepancy between several aerials!
Like I said, reception with a tiny room aerial (plugged, though, into
the distribution/booster thingy in the loft) is already excellent, and
had I known I probably wouldn't have bothered to buy the 18-element
aerial anyway. But I've assembled it now, so it's gonna get used!

MM

This is simple.

1. Plug your postcode into http://www.dtg.org.uk/retailer/coverage.html;
this will return the transmitter that applies to your area, and amongst
other things the compass bearing to it from your postcode

2. Obtain a compass from Milletts or similar (start at about a fiver)

3. Orient aerial.