There's more to it than forward gain for the signal you WANT to hear. F/B and
F/S rejects signals you DON'T want to hear. Otherwise, everyone would just use
omnidirectional antennas. I like that QRM disappears or drops down a bunch when
I turn my F12 flamethrower 90 or 180 degrees away. Sometimes, I'll null on the
QRM instead of peaking on the desired signal. With a beamwidth of around 50
degrees at the -3dB points, the peak is pretty broad. So, there's sometimes not
much to lose by turning away a little from the desired signal.
Kudos to K7LXC and NØAX for their book, "HF Tribander Performance - Test
Methods & Results". It helped me pull the trigger on my new (to me) F12 C-4XL
yagi.
vy 73,Bryan WA7PRC
Date: Mon, 24 Nov 2014 10:11:40 -0800
From: John KK9A
Subject: Re: [TowerTalk] Yagi gain vs rotary dipole.
> Regarding comparing a tribander vs a large monobander, I have tried
> comparing various antennas and stacks and I often find the difference
> very
> hard to notice on my transceiver's S meter. I think with QSB 2 or 3 dB
> is
> just hard to see, especially if you're not listening to a steady tone.
>
> John KK9A
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