At 10:46 PM 3/6/02 +0000, SM2CEW wrote:
>Hi Pete!
>
>Well, I just find it strange that this advertising is not questioned a bit
>more. Any manufacturer could claim that their antennas work on any band if
>we accept F12's way of reasoning. The buyer should be better informed of
>what is really going on in my point of view.
Hi Peter --
I may not have given them enough credit. Here's what Force 12 claims for
the C-3, and I have always found their specifications to be honest:
BAND GAIN NET GAIN F/B SWR
14.000-14.350 12.6dBi 4.6dBd 15dB <1.6:1
18.068-18.168 10.3 2.3 7 ~2.8:1
21.000-21.450 12.8 4.8 17 <2:1 (425 kHz)
24.890-24.990 10.1 2.1 11 <3.2:1
28.000-29.700 12.5 4.4 18 1.5 MHz
So you see, there is less gain and F/B on 12 and 17 meters. Moreover,
because the feed system is set for the other three bands, the SWR is not
attractive there. Still, I have no trouble feeding my stack of C-3Es on 12
and 17 with my SB-220 or the tuners in either of my radios. I think it is
fair for Force 12 to advertise this, because ordinary tribanders do not
have even this modest level of gain and directivity on 12 and 17, and the
traps in the driven element might not be happy with significant power on 12
or 17.
By the way, I've been interested to notice how many stations in Scandinavia
seem to have either tribander or monobander stacks, compred to the rest of
Europe. I'm curious as to why this should be so.
73, Pete N4ZR
Check out the World HF
Contest Station Database at
www.pvrc.org
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