You could be right, Ben. I also worked the ZL9 in 12, and most of the other
Pacific DXpeditions. What worries me is that a 5.2:1 SWR in the shack at
the end of 100' of RG-213 indicates a 15:1 SWR at the antenna, based on a
normal matched loss of 1.2 dB. The additional losses caused by that great
of a miss-match adds another 4 dB, ending up with a gain of -5.2 dBd.
This may be mitigated by the fact that the antenna does have a 6 dB
front-to-back ratio, which would be consistent with a forward gain of 3 dB
caused by parasitic interaction with the 15 meter driven element acting as a
reflector, and/or the 10 meter elements acting like directors, making the
net loss only 1 dB compared to a dipole. Still, it would be nice to restore
the 4 dB lost in the miss-match!
A PS to all the Tower Talk members: I have been delighted reading the posts
on this list-server since I signed up a few weeks ago. It's so much more
congenial and educational here then with those flame-throwin' crazies on the
regular ham radio newsgroups!
Ron N6AHA
-----Original Message-----
From: Ben Bond <bbond@global2000.net>
To: Ron Castro <ronc@sonic.net>
To: <towertalk@contesting.com>
Date: Saturday, January 23, 1999 12:47 PM
Subject: Re: [TowerTalk] Adding 12 Meters to C4
>Ron,
>
>I have a c-31xr and worked zl9 on 12cw/ssb by using a tuner. Two other
>locals WD2K using a C-3S and KM2E using a C-4 have had the same results
with
>a tuner. WD2K runs 100W only. I don't think it's worth the time or effort
>to change a already good design,
>
>GL
>Ben Bond W2PS
>-----Original Message-----
>From: Ron Castro <ronc@sonic.net>
>To: towertalk@contesting.com <towertalk@contesting.com>
To: <towertalk@contesting.com>
>Date: Saturday, January 23, 1999 12:30 PM
>Subject: [TowerTalk] Adding 12 Meters to C4
>
>
>>
>>Has anyone come up with a way to add 12 meters to a Force 12 C-4 without
>>severely impacting performance on other bands? The SWR is quite high on
>12,
>>and even a rotatable dipole would probably work better. I have a Force-12
>>75 meter rotatable dipole 3 ft. above the C-4, and no room below, so any
>>addition would probably have to be on the C-4 boom.
>>
>>Ron
>>N6AHA
>>
>>
>>--
>>FAQ on WWW: http://www.contesting.com/towertalkfaq.html
>>Submissions: towertalk@contesting.com
>>Administrative requests: towertalk-REQUEST@contesting.com
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>>
>
--
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