In article , Christian
McArdle writes
I assumed the top transmitter was the one to go for being nearest (1
mile away); that's the one which said "log periodic" aerial. But I
gather that's not the transmitter to go for then?!

Log periodics are used for transmitters that are located very close to the
receiving station.

How do you work that one out?. Are we at the TX or RX end?. Actually
logs are used extensively at small relay stations but mainly for
logistic reasons..

The advantages of them for this situation a

1. Very even frequency response means that a lower frequency high power
transmission (think analogue) won't overpower the weak low power
transmission which might happen to be at a higher frequency (think digital).

That can be either way round and why should a log aerial be sooo much
better?. Sorry but that reasoning is rather weak...

Log periodics are inherently wideband and suitable for digital transmissions
that may be far from the original analogue band of the site. They tend to be
more expensive and have lower gain than a conventional Yagi, though.

Not so simple as that. Wideband yes, but if your digital transmissions
are in a group setting like Crystal palace in London, no particular
sense in a wideband aerial there..

2. Very tight side and rear lobes help prevent the reflections and ghosting
that are characteristic of being in a high power area close to the
transmitter.

Not really that simple as the AGC will adjust the TV RX gain
accordingly. Anyway digital, does it matter?.

--
Tony Sayer