I wounder if there is anyone out there that has tried the
6 square ant (similar to a 4 square) and if so how the
phasing/power splitting was solved.
Don't know if 9V1XQ is the "inventor" of this antenna but
I have seen some MN config files that came from him.
73 de Jim SM2EKM email: jeh%kiona.dnet@hk.mobitel.telia.se
>From Tony Brock-Fisher <fisher@hp-and.an.hp.com> Fri Sep 30 11:35:56 1994
From: Tony Brock-Fisher <fisher@hp-and.an.hp.com> (Tony Brock-Fisher)
Subject: advice on ferrite beads for RF coax chokes needed
Message-ID: <9409301035.AA08653@hp-and.an.hp.com>
Tom-
Think of a bead on the coax as a series L and series R. If the bead
material doesn't give enough L, you just need more of them on
the cable. The length of beads doesn't matter, just the number.
Theoretically the beads don't have to be right next to each other -
they could be 5 feet apart and still do the job. As far as how many
is enough, the idea is to raise the impedance for signals travelling
on the outside of the cable. As you do this, the amount of current
that flows decreases. It never goes to zero, but at some point it
gets small enough so you don't care any more. We use some big beads
here at work, and if you put one turn of wire thru them and measure
them with a Z-bridge, they look like about 70 ohms reactive. Using
the usual rule of thumb for this sort of thing, if you get 4-5 times
as much reactive impedance as the resistive impedance of the circuit
(50 ohms), you're essentially there. So that says about 3-4 of these
should do it. This bears out my experience at home. ( I always start a
contest with a full coffee pot and a full box of beads. If something
doesn't work, first throw a bead on it. Then have some coffee!)
-Tony, K1KP, fisher@hp-and.an.hp.com
>From gjk@hogpa.ho.att.com (Gerald J Kersus) Fri Sep 30 13:07:59 1994
From: gjk@hogpa.ho.att.com (Gerald J Kersus) (Gerald J Kersus)
Subject: PHASED Half Squares!
Message-ID: <9409301207.AA03396@hogpc.ho.att.com>
I, too, started looking at phasing two half-squares for 40M. The patterns
using ELNEC look pretty promising. However, looking at the resulting
impedances of the two antennas was discouraging -- the matching network
would not be very simple. I started modeling another arrangement inspired
by K3LR's QST article on his 160 M array. Feeding one antenna and adding
the right amount of inductive reactance to the other produces pretty good
results using ELNEC. With 24 feet of separation and a 40-ohm load at the
feed point of the "reflector", ELNEC shows a gain of 7.2dBi and a F/B of
15 dB. Not too shabby for a wire antenna up only 40 feet and that doesn't
eat up a lot of real estate.
My main problem was finding the four trees tall enough and the right distance
apart (and also oriented so I can point the antenna to Europe). I've found
the trees and put up one of the antennas, but it doesn't work as well as a
test antenna I put up a month ago. It may be too close to the tower. (One
end is only about 25 feet from the tower. ELNEC indicates that this should
be ok, but there may be interactions with other antennas. K2PH came over
last night with his new Autek RF analysist. The antenna is resonant about
where it should be. We need to analyze the readings to figure out how to
make it play better before I take the time to put up the second
half-square. (My wife asks why I always wait until a month before CQWW
to start these antenna projects.)
Gerry, W1GD
>From Douglas S. Zwiebel" <0006489207@mcimail.com Fri Sep 30 04:28:00 1994
From: Douglas S. Zwiebel" <0006489207@mcimail.com (Douglas S. Zwiebel)
Subject: Hello Indianapolis types!
Message-ID: <90940930032809/0006489207PK3EM@MCIMAIL.COM>
I will be in the land of the speedway for a business type event this Monday.
I will arrive sometime (late afternoon) on Sunday. Anybody home wanna
share a gab?
de Doug/KR2Q
KR2Q@MCIMAIL.COM
>From p_casier@ub4b.eunet.be (Peter Casier) Fri Sep 30 14:59:32 1994
From: p_casier@ub4b.eunet.be (Peter Casier) (Peter Casier)
Subject: Announcing OT4T, CQWW phone
Message-ID: <199409301359.AA24452@ub4b.eunet.be>
OT4T will be our M/S effort in the upcoming CQWW phone test, running from
the QTH of ON4UN.
Ops: ON4WW, ON4UN, DL1SBR, DJ4AX, DL5XX, DK1FW and ON6TT, assisted by a
vaste group of spotters.
Unfortunately, F6EXV, who helped us ending as #1 EU M/S last year, is still
in Africa and will not be able to join us.
QSL (will be a multi-colour card) via ON4UN
Skeds with DX stations would be appreciated.
73-Peter
ON6TT.
p_casier@ub4b.eunet.be
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