This is on the comment, "Go Vertical!" not the Vee Beam.
I wish to share some good news about a vertical with you guys.
You always hear mixed opinions about verticals. Some like them. Some hate
them. The reason is that some people have success with them and some people
have problems with them. Typical problems and causes of poor performance
are poor ground or [old] traps deteriorating over time.
About 15 years ago I read about a different type of all-band vertical which
did not suffer from either of these two causes of poor performance. To this
day I still use it, even though I have space for just about any antenna.
I use a "Vertical Dipole". It is center-fed with 450 Ohm Ladderline, all
the way to the rig, thru a true symmetrical matchbox (not a balun and
T-match). The first one I built was 5m (~15.5 ft.) on each side. The
current one is 6m (~18.6 ft.) on each side. The feedpoint is about 9m (~28
ft.) above the ground, so that the bottom of the antenna is about 10 ft. off
the ground and out of reach of children.
I can match this antenna on ALL bands from 80m thru 10m.
Now to qualify that statement, I need to compare its performance to another
antenna. My other antenna is what Stuart recommended, a horizontal dipole,
center-fed with 450 Ladderline, all the way to the shack, matched also with
a true symmetrical matchbox (no balun and T-match). The dipole is 20m on
each side (so, it's a half wavelength for 80m).
On the upper bands, I use the vertical dipole all the time. Its almost
always a better performer there, in ALL directions. For 40 and 80 I switch
a lot. The horizontal is clearly superior for NVIS (local) work, but things
change for mid-range and especially DX work. When I work transatlantic on
80m, the short vertical works equally well to the (full-size) horizontal
dipole. On 40m, it works better. I also noticed in CQWW DX (where my goal
is to work anything except other German stations) that the vertical is
almost always stronger than the horizontal. I guess for U.S. operation, you
could say for work outside of my own state, the vertical outperforms the
horizontal in all directions (40m band).
This "Vertical Dipole" is really a convenient, low-cost, good performing
antenna. I built my first one using an old army Jeep Whip for the top
section and copper wire for the lower section. The mast which extended to
the feedpoint was cheap wood. ONLY ONE PROBLEM, the wood caught fire and
burned. There is high voltage at the feedpoint so it needs to be well
insulated and kept away from the wood. Lesson learned.
In the meantime I bought a commercial version of this antenna from the
German company, "Titanex". It is free-standing and maintenance free.
I also highly urge people to feed these ladderline antennas with symmetrical
matchboxes, not asymmetrical matchboxes. The best thing going is an old
Johnson Viking matchbox, but a good, modern, low-cost box is the MFJ-974.
I'm no great fan of MFJ, but I bought the box out of curiosity, tested it,
and it worked just fine on all bands (for 100w). I then sold it.
If you must use a "T-Match" or other asymmetrical matchbox, search through
the Ten-Tec reflector's archives for a description of "The Monster Balun"
which Bob described here about a year ago. And of course the very best
asymmetrical matchbox is the Model 238 from Ten-Tec.
Bottom Line, if you are searching for an all-band antenna and space is
limited, or if simplicity is desired, this is the best antenna I've come
across in my 45 years of hamming.
73
Rick
DJ0IP
-----Original Message-----
From: tentec-bounces@contesting.com [mailto:tentec-bounces@contesting.com]
On Behalf Of ron
Sent: Tuesday, February 15, 2005 7:22 PM
To: 'Discussion of Ten-Tec Equipment'
Subject: RE: Fw: [TenTec] Ten Tec Vee Beam?
Fine business Caitlin.
That's tiny. Geographically and physically, a Vee antenna won't do it! (heh
heh)
Yes. Go Vertical! :)
Ron
Wb1hga
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