Andy wrote:
>> It's no fair trying to claim that dBd means "gain over a dipole in free
>> space"
>
> But that is EXACTLY what it means!!!
Whilst you are technically correct (and the ARRL Antenna Book agrees
with you - 21st Edition page 11-2), I think Tom W8JI covered this fairly
well back in 2004 in his posting "dBd vs dBi misuse" and how the dBd
figure can be misleading if not used in a consistent manner. His post
is archived at
http://lists.contesting.com/_towertalk/2004-06/msg00506.html The ARRL
Antenna Book agrees when it says "Each frame of reference is valid, as
long as it is used consistently and clearly". I don't think many would
agree that comparing one antenna in free space to another over real
earth is either consistent or clear but more like comparing apples to
oranges! They both need to be compared in the same location and at the
same height or both compared in free space. Mixing and matching points
of reference could be seen as an attempt to deliberately mislead.
Now, to veer off track a little..... how can someone patent a "Balanced
dipole antenna" as recently as 2007? Reading the description, it just
sounds like, well, a dipole with a balun!
http://www.freshpatents.com/Balanced-dipole-antenna-dt20070809ptan20070182656.php
Vy 73
Andrew AC6WI
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