Just my thoughts:
Seems like I saw slopers mentioned. I have several center fed, half
wave slopers on about a 45 degree angle for 75 and 40. On 40 they are
just OK state side, but work well for DX. I'd not recommend them for
state side unless you have enough to switch into for direction and
distance. For close in, broad side, or even 180 degrees might be
preferable for close in, although IIRC they aren't a ball of fire off
the back side
I'm in Southern MI about 25 MI W of the S end of Saginaw Bay, so I'm
thinking we probably have similar propagation, although for state side
contacts, it's pretty much 090 to 330. From 90 to around 135 is pretty
much short hop, or roughly 130 to roughly 5oo miles the rest is from
roughly 120 to about 2500 miles As I have one sq acre antennas favoring
distances and direction are limited and definitely a compromise.
If I were serious about omni state side I'd probably go for a pair of
inverted V fans at 70 to 80 feet at right angles to each other, but I
don't think you have that height as an option. It's a compromise, but I
have the tower although the antenna anchored in the front yard would be
definitely temporary. Getting fan slopers would allow switching to
which ever favored the direction and distance, but you'd need at least
three of them, if not 4 and that's a lot of wire and feed lines. It's
unlikely you'll get full use of 75 or 40 without a tuner.
73 es good luck,
Roger (K8RI)
On 10/6/2015 3:02 AM, Jim Brown wrote:
Hi Rudy,
You've received some really "off the wall" replies to your question.
Some thoughts from the left coast, interspersed below.
On Sun,10/4/2015 7:18 AM, Rudy Bakalov via TowerTalk wrote:
I need antennas for working the US and Canada on 20-15-10 from my VE3
QTH. I'd appreciate any and all suggestions.
Currently considering 1) vertical dipoles and
Verticals are pretty cool, but not much radiation above about 30-40
degrees, so you could be weak in W1/W2/W3/W8/W9.
2) a curtain of 3 stacked dipoles (or inverted Vs) from 10' to 30'.
There are serious misconceptions about the height of horizontal
antennas and their effectiveness at low angles. Low horizontal
antennas are NOT better for NVIS, they are worse for both short AND
long distances. The IDEAL NVIS antenna is about 3/8 wavelength high.
Anything else? Do keep in mind that from VE3 the US is from ~160 to
~330 degrees azimuth and I do not want to rotate the antenna.
I strongly suggest that you STUDY
http://k9yc.com/VertOrHorizontal-Slides.pdf (CAPS added for
emphasis). There's "simple" and "too simple." Fan dipoles at a "good"
height could work really well for you -- 30-40 ft is a good starting
point -- but any good dipole has a null off the end, so you really
need two at right angles to work both S and W. With dipoles, the only
thing that really matters is the nulls off the ends. Longest US DX for
you is CA, OR, WA, so I suggest that you try to be approximately
broadside to San Francisco with one fan and to MS with the other, then
a simple switch to go between them. The west fan will be killer from
KS to CA/OR/WA and will do fine in NTX, etc. The S fan will be great
from W1 to FL and TX. There are photos in this presentation
http://k9yc.com/LimitedSpaceAntennasPPT.pdf
of a fan dipole I used in Chicago on a small city lot. Very easy to
build -- the spacers are 1/2-in PVC conduit. I used these antennas
here in CA before I found space to turn aluminum. :)
73, Jim K9YC
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73
Roger (K8RI)
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