[Top] [All Lists]

[Fwd: Re: [TowerTalk] V-Beams (long-delete if no interest)]

To: <>
Subject: [Fwd: Re: [TowerTalk] V-Beams (long-delete if no interest)]
From: seay@Alaska.NET (Jan & Del Seay)
Date: Sun, 02 Mar 1997 16:28:20 -0800
Message-ID: <>
To: <>
Date: Sun, 02 Mar 1997 16:25:37 -0800
From: Jan & Del Seay <>
X-Mailer: Mozilla 3.0 (Win16; I)
MIME-Version: 1.0
To: Jim Reid <>
Subject: Re: [TowerTalk] V-Beams (long-delete if no interest)
References: <>
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit

Hi Jim: 
Having plyed with long-wire array, I would like to make a couple of
comments, re your project. 

   a) The idea is sound - but remember that if you use resonant
      wires for bi-directional use, (an antenna is said to be resonant
      when standing waves are present) the frequency range is really
      limited, A 180 degree phase reversal is forced at the far end,
      as the direction of travel reverses. Therefore, a very narrow
      range of frequencies are available where the voltages in each
      direction are additive. Not likely you will get much gain over
      2 or more amateur bands. By terminating the wires, you eliminate
      the reverse voltage and gain is obtained over a large frequency

   b) Using PVC, or similar material for spreaders is probably not a
      good idea due to the weight of the material. The best spreaders I
      have used are 1/8" thick X 6" long X 3/4" wide wood pieces that
      have been boiled in parafin. Very light, and impervious to weather
      and UV radiation.

   c) The Amidon baluns are not extremely rugged. I bought three of
      their 6:1 baluns for 300/50 ohm feed of folded dipole elements
      and the longest any lasted at 1.5 kw was 2 months. A better
      choice (but more pricey) is the Palomar Balun that is designed
      for tuned feeders with very high vswr. At $80.00 it is twice
      as high priced, but I haven't been able to destroy one.
      Of course, using a link-coupled matching device (such as the
      Johnson Matchbox design) is the best choice.
Remember to keep the high swr on the tuned feeders, not on the coax.

Good luck with the project. Vee Beams and Rhombics are the best
antenna' around. Still kick butt even with all the new technology!

73  de KL7HF

FAQ on WWW:     
Administrative requests:
Sponsored by:             Akorn Access, Inc. & N4VJ / K4AAA

<Prev in Thread] Current Thread [Next in Thread>
  • [Fwd: Re: [TowerTalk] V-Beams (long-delete if no interest)], Jan & Del Seay <=