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Re: [TowerTalk] Loop vs Dipole...I'm original "asker"

To: Richards <jruing@ameritech.net>, towertalk@contesting.com
Subject: Re: [TowerTalk] Loop vs Dipole...I'm original "asker"
From: "Dan Zimmerman N3OX" <n3ox@n3ox.net>
Date: Fri, 27 Jun 2008 20:50:01 -0400
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
" I wonder WHY NOT
worry about trying to cover the bands with good antennas?"

Because it's very easy to make ham radio *frustrating* instead of
*fun* if you try to do too many bands in a small space without knowing
what you're doing.

"Maybe
one of those Force-12 43 foot mono pole masts they tune up on
all bands... 160 - 10?  Or something else.  I cannot believe I have to
give up on those low bands entirely."

You don't have to give up on the low bands just because you're on a
small lot... I use a 60 foot tall vertical to good effect with low
loss matching at the base, and I do well on 160 through 30 with that.
But this is my matching system:

http://n3ox.net/projects/sixtyvert/allnetworks_lg.jpg

If you really want to build one for a first station, or spend a
thousand dollars on a fancy remote tuner that will handle matching an
extreme impedance on 160, it can be done.... but maybe a more fun
solution would be to buy a 33 foot fiberglass pole (Jackite comes to
mind) run a wire up the side and be happy with a good signal on 40m
for now and forget 160/80.

I run 160m on a small lot with 100W using an FT-857D as a rig.  I
built a receiving antenna to help me (a little) to hear through the
static:

http://www.n3ox.net/projects/flag

Would I be doing all of this if I were putting together a station as a
new ham?  No way!

I used to have a wire antenna about 130 feet long fed against ...
well.. essentially nothing; just the wiring in my shack and a ground
rod and wire.  It would "tune up" just fine on 160m and 80m (and all
other HF bands).  That is, I could get the tuner to show 1:1 SWR.  Of
course, the tuner would arc like crazy sometimes (@ 100W!!) on 80m
because I was end feeding it, but I could make some contacts.  On
160m, I managed to work about 10 countries and could reliably make
contacts but not ragchew so well with the Eastern half of the US.  One
night, I had a pair of amazing contacts with an OK2 and a 9A2 station
on 160 who managed to hear me on that miserable wire.  Eventually, I
basically gave up on working anything at all on 160m and 80m; I took
the wire down to put up a tribander, and added a 30m dipole, a 17m
rotatable loop, a 12m yagi, and a 40m quarter wave vertical.  I could
stay up all night working amazing world wide DX with my GOOD antennas
on the higher bands, so I neglected my not-so-good antennas on the low
bands.  I put up a low inverted vee on 80 eventually but never really
picked that band up again, until recently.

Now I put up this vertical and receiving antenna and with the same
100W I've increased my country count to 94 worked on 160... and that
OK2 and that 9A2 that I just barely worked maybe 8 years ago?  They
come in 599+10dB now.  The antenna is a full size quarter wave on 80
and even with my small radial system and 100W I've worked nearly 100
more countries in the last couple years, bringing me up in the high
120's.

Now, that doesn't mean it's not worth *tasting* all the bands, but I
think doing a few bands really well and ignoring some others is just
fine, especially if you're starting out.

The problem is that "tasting" 160m and 80m can cost a lot of money for
overall very poor results if you're not on top of your antenna theory
and practice.  If you actually manage to efficiently feed a good bit
of power into a 43 foot vertical on 160m, I have it on good authority
that the voltage at the base of the antenna can light weeds on fire
;-)

I tried a 40 foot vertical on 160... what a stinko antenna, and I even
matched it right at the base; I didn't have 15dB of feedline loss
making the transmitter happy!

You can certainly do low bands from a small lot, but as someone who's
doing low-band low-power work from a small lot, I can say that 90% of
the battle is knowing your antenna book inside out, so reading a bunch
and planning is much more effective than hemorrhaging money in the
direction of big amplifiers and commercial antennas.  Basically, if
you're interested in the low bands, don't trust anyone trying to sell
you a big signal on 160m and 80m ... spend money on books first...
antenna book, ON4UN's Low Band DXing, and work on antenna building on
the higher bands in the meantime where it's easier to deal with the
antennas.

73,
Dan
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