Hi Ken...
I have a REAL problem with your reported results....
If your assumption that the Force 12 is 4 S-units better is correct, then
allowing even a measly 3dB per S unit, means that your high antenna has a
-12dB gain compared to the F12... I don't think so! ...
(If your receiver is near the ideal of 6dB per S unit, then the difference is
24dB !!!!!!)
In other words, the F12 yagi has 12 (to 24) dB gain over another yagi on 20
meters... (Be still my beating heart.)
Now, assuming your old antenna has 6dBd of gain and assuming a 12dB
difference (3dB/S-unit) _at the same height_ means 18dBd of gain, total...I
am certainly interested in taking a drive along the boom of an 18 dBd gain
antenna for 20 meters.....(If we assume the higher figure we get a 30dBd gain
antenna, and we will need an airplane to cover that boom in one day...)
It is apparent from the information you presented, that the height
differential between the two antennas means that the peak response(s) of the
lower beam falls at, or near, the null(s) of the higher beam....This,
predictable, result is the reason for stacked arrays, where the peak
responses of antenna A fills in the nulls of antenna B , which is at a
different height... Lets see how the two antennas play on an 8000 mile
path...
I have admiration for Force 12... They understand the concepts of radiation
efficiency and minimizing (I^2R) losses... If you read my comments on this
subject of a few months ago you will see that I proposed that a fresh stack
of C3's, with fresh coax and newly soldered fittings, just may outplay an
older stack of bigger tribanders, with loading coils (lossy), weathered
coax, and fuzzy connectors... But, no where in those comments would I credit
a 12dB difference....
Nice try, but no banana...
Cheers ... Denny
>From H. Ward Silver" <hwardsil@seattleu.edu Sat Sep 16 16:39:01 1995
From: H. Ward Silver" <hwardsil@seattleu.edu (H. Ward Silver)
Subject: Grateful Ed Team Lineup
Message-ID: <Pine.3.07.9509160801.I8986-9100000@bach.seattleu.edu>
Thanks to those who stepped up. Sorry I couldn't accomodate
everyone...maybe I should've started a second team ;-)
The Ed's are:
N0AX, K7SS, AA7FT, KF9PL, NN7L, K7LXC, KI4HN, K1DG, KE2PF, N6TR
Some worthies there, eh wot?
See you at 0000.
73, Ward N0AX
>From David O. Hachadorian" <74752.115@compuserve.com Sat Sep 16 19:14:58 1995
From: David O. Hachadorian" <74752.115@compuserve.com (David O. Hachadorian)
Subject: Hurricane nets
Message-ID: <950916181458_74752.115_EHL67-1@CompuServe.COM>
There are at least two hurricane nets operating today, on 14268
and 14328. There may be some other net frequencies, and some
traffic is being handled on side frequencies. Folks involved in
the phone Sprint tonight should be careful to give these nets a
good 5 Khz buffer, and also keep an eye out for other traffic
freqs.
Dave, K6ll
74752.115@compuserve.com
>From kn6dv@qnet.com (Will) Sun Sep 17 01:03:14 1995
From: kn6dv@qnet.com (Will) (Will)
Subject: SCCC team 1 and 2
Message-ID: <m0su6yM-0000MwC@cello.QNET.COM>
Hello all, here the SCCC team 1:
KJ6HO, N8SR, K6LL, W9NQ, KI7WX, WK6V, NC6U, N6HC, W6HAL, W6UQF.
team 2:
WA7BNM, K6NA, N6VR, AB6FO, N7QQ, KC6CNV, KA6SAR, K6VNX, W6MVW, KN6DV.
GOOD LUCK to all...
73 de Will, KN6DV
vice pres. SCCC
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