On 2/14/02 12:45 PM, Macie, Gordon at gmacie@xmmcorp.com wrote:
>Thats what Rick NQ4I suggested.. I am following his advice... I have a 4 el
>20 a 5 el 15, 2 el 40, 6 el 6 mtr.
Let's see 17 feet of mast, 3 feet in the tower, that's 14 feet of mast
above the tower for four monoband antennas.
Aren't they gonna be a little close for comfort? 14 foot separation
between the 4l20 and the 2l40 seems ok, but where do you put the 5l15?
>I have been reconsidering my plans. I
>have been looking at a c31xr or a tennadyne log periodic.. if i go with
>either i would eventually want 2 stacked high / low for different angles...
Stacking is a great idea, but there are a lot of variables. How high is
your tower? I wouldn't stack a tribander toward europe lower than about
45 feet -- although one on the carribean could be placed perhaps down to
35 feet. Monobanders are a whole 'nouther matter, since they can be
stacked at variously hieghts / distances. In general, you need more tower
space to stack a group of monobanders. But you can pick optimal stacking
distances. Stacked tribanders are a compromise.
>I have gotten a little cautious toward pursuing my initial goal
>of 3 100 ft towers. I have been having some knee trouble and not sure ill be
>able to do any climbing and that may just be too much maintence. I am
>confused with all the options. Have gone back and forth considering a free
>standing trylon and just use a crane. Maybe 1 guyed and 1 freestanding.. I
>AM CONFUSED !!!!.
Try thinking of it another way. What do you want to accomplish with your
antenna set up? Do you need antennas to feed two different radios, or
just one? For the first radio, what would be sufficient for each band? Do
you want to cover multiple propagation angles? Which angles are
important? Do you want to cover multiple directions? Can you rotate those
directions, switch them, or do you need to cover them similtaneously?
What bands do you need to cover? Do you need gain on each band
(especially for the low bands)?
What do you need for the second radio? An R7? A dipole? A tribander and
wires? More monobanders? Can you divide your antenna system by band and
use one set of antennas for both radios? (Works great with monobanders --
which is how W4AN does it)
Think about each question and draw up a Good, Better, Best scenario. Try
to consider how much each improvement is worth to you. Try to narrow it
down to the least antenna configuration that gives you the maximum value.
Now, figure out how many towers you have to put up to do that. You can
put a lot of stuff on three towers. NQ4I has a full M/M station going on
three towers.
(Yes, that's a lot of drivel from a guy who just has a tribander at 50
feet)
My wife has been looking at some nearby property with 10 acres (that's
far more than we can afford right now). I've run the mental exercise --
if I moved, what might I put up?
I came up with the following hypothetical solution:
Tower 1:
Force-12 tribander with 2 el 40m @ 95-100 feet, rotatable
Force-12 tribander @ 70 feet, fixed on europe
Small tribander @ 45 feet, fixed on carribean
80m four-square suspended from ropes or sloping dipoles to EU, West,
Carribean
160m shunt feed
Tower 2:
Medium to large tribander with 40m @ 65-70 feet, rotatable
80m inverted V or dipole
This particular solution uses a lot of tribanders, which avoids a lot of
antenna interaction headaches. The first two tribanders are stackable.
The second tower is mainly for the second radio.
The one key feature is that the tribanders can be pointed at JA, EU and
the Carribean in a switchable fashion. I used a setup at NQ4I's 20m
station and am sold on the switching configuration.
The compromise is in the tribanders. Monobanders might require long
rotatable masts, or swinging side mounts, or more towers to hold a bunch
of fixed monobanders. I dunno, perhaps I need to run the thought problem
through with monobanders in mind....
>I dont like crankups they scare me..
They can be scary. They are usually good for holding ONE antenna.
Freestanding or guyed towers are more versitile.
>Who is the guy with the masts do you have a phone number ?? what part of
>town..
Bill Wall. K4OGG gave me the number of (706) 466-4353 four years ago.
I think he's in Lawrenceville.
Bill Coleman, AA4LR, PP-ASEL Mail: aa4lr@arrl.net
Quote: "Not within a thousand years will man ever fly!"
-- Wilbur Wright, 1901
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