[TVARC] Flag pole verticals

Tue Apr 21 15:28:45 EDT 2020

On Tue, Apr 21, 2020 at 8:53 AM Ken Peters <kenpeters913 at gmail.com> wrote:

> Hi to all,
> I am brand new to the club and joined during this WuFlu shutdown. So Ive
> not even been to a meeting. I had a CW license when I was 13-18.  Then life
> took over.
>   I recently bought a FT-818ND and am excited about getting my tech
> license and getting into this and meeting members. Ive been on this email
> list and reading these for a couple weeks now but these communiques about
> antennas really got me curious.
>    It gave me an idea which may be totally stupid since I am such a
> pre-novice to this.
> Why can’t a conventional flagpole, (with a flag) be used? Run a wire up
> the pole, etc.?
>    Im sure its been thought of before; what is the flaw in this idea?
> Thanks
> Ken Peters
> Û

Hey Ken, welcome to the club!

You can hook up to just about anything and get a signal out, but the desire
is to get some bang for your buck when you do it. A flagpole can be used as
a radiator in a couple of ways that are effective, and a bunch of other
ways that are no real good.

The two ways that work well are using it as a "shunt fed vertical" or as a
"series fed vertical". A shunt fed vertical uses a grounded vertical mast
or wire, which sounds like the easiest, but the problem is that you don't
attach your feedline conveniently at the bottom. It has to attach anywhere
from about 1/3 of the way up to near the top, then it has to run away from
the pole until it gets far enough that it doesn't interact with it. This
can be managed if you have a feedline that's small and blends in well
stretching from, say, your eaves to the flagpole somewhere along its
length. Hopefully low enough to avoid snagging a flag.

The problem is, the flagpole heights allowed around here are short for this
kind of antenna. 33 ft or more is better. Plus it's not completely stealthy
because of that extra wire running from the pole.

A "series fed vertical" has the advantage of having the feedline connected
at or near the bottom of the pole, so it's easy to conceal. However, this
type of antenna needs to be isolated from ground. So the aluminum antenna
in my yard will need to be cut free of the part set in the ground and an
insulator section inserted.

Our flagpoles are still a bit too short for the frequencies we work on as
hams, so we add a loading coil and an antenna tuner to help match our
antennas to the signal from our transmitter. For listening, it doesn't
matter so much. But for putting out a signal, efficiency matters a lot.

However, if you don't mind the vagaries of 10m and 6m, you can simply pull
up a vertical half wave dipole antenna that's about 17 feet long for those
bands. But it takes a longer antenna for anything else in the HF bands
(though 6m is actually VHF, you get my drift.)

If we could have 22 foot or 24 foot flagpoles here, it would give us a lot
more options, but 20 is our local limit inside The Villages.

Good luck on your license prep!

Mark Graybill, W8BIT
TVARC Vice President

>
> > On Apr 20, 2020, at 12:26 PM, Tom Crawford <tmcsail at sbcglobal.net>
> wrote:
> >
> > Hello to All,
> >
> > I was wondering if someone could share with me their address so that I
> could just drive by and see a good flag pole vertical installation (no
> eyeball of course!) to guide my aspirations for a working HF station.
> >
> > I’ve read all the good info on the website.
> > I live down in Fenney.
> >
> > Much appreciated and 73,
> > Tom Crawford
> > W3TMC
> >
> >
> >
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