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Re: [TenTec] TenTec Digest, Vol 56, Issue 9

To: Discussion of Ten-Tec Equipment <tentec@contesting.com>
Subject: Re: [TenTec] TenTec Digest, Vol 56, Issue 9
From: "Tom Childers, N5GE" <n5ge@n5ge.com>
Reply-to: n5ge@n5ge.com,Discussion of Ten-Tec Equipment <tentec@contesting.com>
Date: Wed, 08 Aug 2007 11:49:06 -0500
List-post: <mailto:tentec@contesting.com>
On Tue, 07 Aug 2007 20:01:42 -1000, you wrote:


>No doubt that Steppir antennas are really nice, and they can be adjusted 
>for super low SWR on the line to the antenna, not just between a tuner 
>and the  rig.  That is really neat, and I'd love to have one myself. 
>However, it is not necessary to have a Steppir or other remotely tunable 
>system, or a multiple resonance antenna (such as one with traps or 
>resonant stubs or coils as with Gap or Butternut) in order to have high 
>efficiency on several bands. A plain vertical can be tuned (with a tuner 
>in the shack) to work  efficiently over greater than an octave (like say 
>60, 40, 30 and 20 meters) .
>You don't have to spend a lot of money to have an efficient antenna. In 
>fact the cheapest simplest homebrew antennas are often more efficient 
>than the expensive, ready built (some assembly required) ones that have 
>moving parts, coils and other do-dads on them.
> CATFISHTWO@aol.com wrote:
>> in a word... Steppir
>> I have a 3 ele steppir 6-20 m beam and I love it. it is a perfect antenna  
>> on 
>> every frequency. no tuner needed. they make beams up to 40m and a couple of  
>> verts up to 80 meters. 
>> worth every penny       tom N6AJR
>> ==========================================================
>> In a message dated 8/7/2007 9:01:29 A.M. Pacific Daylight Time,  
>> tentec-request@contesting.com writes:
>> Alan,  absolutely a great post, and well said.  You are right on the money!  
>> Effective power is the key.  An improved or efficient antenna is the  lowest 
>> cost route to effective radiated power.
>> A point was made in  the QRP forum at the local ham convention Sat.   Even 
>> if 
>> you are  using one of the shortened antennas, you still have to keep the 
>> high 
>> voltage ends well away from conductors and screening foliage, or other  
>> detriments to the high near field levels.
>> And the high current  magnetic field concentration near the feed point 
>> should 
>> also be protected  from coupling to conductors.
>> A dipole can be shortened to 60 per cent  of full length and maintain 
>> efficiency in the greater than 90 per  cent
>> value.  You just have to have it in the clear of detractors from  its field. 
>> Low profile antennas like the Moxon rectangles can provide beam  performance 
>> in less than traditional Yagi dimensions.  Use of low  loss insulators, 
>> conductors,  and fasteners is key to small antenna  use.
>> An easily elevated small beam may be the answer for aging  hams.  The masts 
>> from Force 12 that were marketed for portable use  come to mind.  Motorizing 
>> such an elevating cable for that mast might  be fairly simple.
>> ************************************** Get a sneak peek of the all-new AOL 
>> at 
>> http://discover.aol.com/memed/aolcom30tour
>> _______________________________________________
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>TenTec mailing list

Everything you say is true, but you forgot that 1/4 wave verticals have no gain
and unless you put it on a pole with a ground plane of at least three radials in
the air or put a lot of radials in the ground for a ground mounted vertical, the
antenna may have negative gain.

I'm "an aging ham" over sixty and climb my tower at least once a week to make
adjustments and check for problems.  I also use vertical antennas at my QTH.  I
just recently constructed a ground plane for 30m.  It is mounted on a 4x4 square
post at about 8 ft and has three horizontal radials spaced at 120 degrees apart.
the radiator is made from aluminum tubing I had laying around.  It outperforms
an inverted vee dipole at 40 feet consistently.

One of the other folks that replied to the thread said vertical antennae don't
have good low angle radiation.  He is wrong, they have a much lower radiation
angle than a dipole and are better for long haul DX than a dipole.  A study of
the ARRL Antenna book will confirm this.

One other comment.  What does this have to do with Ten Tec Radios? 
Tom, N5GE


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