[SixClub] New to Six Meters

[Steve Katz]

I've written this many times, but some missed it and for some I think it
just doesn't sink in.  VHF is very different from HF.  If you want to make
contacts only when the "band's open" on six, you won't be busy very many
days a year.  Having good antennas is mostly for the *OTHER* 340 days a
year, when the band is *not* open.  Since most VHF-UHF contacts are tropo
scatter, a mode that can propagate signals very long distances only when
larger antennas are used (or operating locations are greatly advantageous,
like being on a mountaintop), every small antenna improvement can yield
large, noticeable improvements in working radius.  Here's why "working
radius" is important:

Say you have a 6m vertical and a 100W station and can usually work other
stations within a 50 mile radius.  With 6m activity and population density
as it is, that means you can regularly work 20 stations.  Now, you improve
to a horizontal rotary beam antenna and find you can usually work other
stations within a 200 mile radius (not an unusual change).  Now, you've just
improved your "coverage area" from 7854 square miles (50 mile radius) to a
whopping 125,664 square miles (200 mile radius).  Assuming population
density remains equal, and number of 6m operators per square mile remains
equal, you've just increased how many stations you can regularly hear and
work, from 20 to 320.  Yes, twenty to three-hundred twenty.  So, you've
multiplied the number of stations you can routinely contact by a factor of
16 to 1, simply by adding a small beam.

This is *not* an unusual improvement, by any means.  Remember, 90% of all
stations you can contact on six meters *will* be "weak," fairly close to the
noise level.  That's the nature of VHF SSB-CW work, and what makes it
interesting and exciting in the first place.  It doesn't matter what you
run, how big your antenna is, or where you're located, this fact remains:
90% of your contacts will be "weak."  As you improve your station, your
antennas, your location, the QUANTITY of weak stations you can work will
increase dramatically, but 90% will still be weak -- there will just be a
lot more of them.

And geometry's a powerful thing.  When you increase your working radius, you
increase the number of stations you can contact by the square of the radius.
A two to one increase in radius yields a four to one increase in the
population you can contact.  A three to one increase in radius yields a
*nine* to one increase in the population you can contact.  It's simple math,
but easy to forget when you're considering antenna changes.

I have a 7L 6m horizontal beam on a tower, and also a "Ringo" 6m vertical
(1/2-wavelength, works well for FM-repeaters -- far better than the
horizontal beam, actually, since it has compatible polarity) on the roof of
my home.  If I tune around on six, on an average Sunday morning, turning the
beam around listening for weak stations, I can usually hear 10-20 stations
on the band (no openings, no contests!).  If I switch to the vertical, that
quantity drops to maybe two or three stations.  Big difference.

73 & good luck!

Steve WB2WIK/6






It's a question of how big a signal you want to have, and that's at least in

part relative to what sort of signals others have.  The larger an antenna 
you go to (more accurately, the more effective, the more gain and other 
factors, but let's say gain as the most obvious one -- and height above 
ground, how high the antenna will be) the greater your ability to get 
through when conditions don't quite favor you, when the band isn't quite 
open, or isn't all the way open, etc., and if you have one of the smaller 
stations or signals, you may have to wait for many, many others to get 
through to a DX station before you get through.  If you just want to talk to

your buddy a few miles away, it doesn't take much.  If you want to work 
DXCC, get through on the first call to rare stations, etc. you might want to

upgrade a little at a time, etc., which is what most of us have done.