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[TowerTalk] VERY simple 40m antenna help

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Subject: [TowerTalk] VERY simple 40m antenna help
From: ve7hcb@rac.ca (Chris BONDE)
Date: Wed, 14 Nov 2001 14:28:59 -0800
Has anyoe tried an upside down vertical?
Rmember reading about one for 40m awhile back.  If corrct in my recall, it 
had the readial on the top and the vertical feed up there hanging 
down.  From a tree.

Chris opr VE7HCB


At 12:41 PM 2001-11-13 -0600, n4kg@juno.com wrote:

>The simplest (Low) antenna that will be useful for
>working DX is a VERTICAL with a GOOD radial field,
>which means 30 or more radials as long as you can make
>them, up to 1/4 Wavelength.
>
>A wire can be dropped from a tree limb for the vertical element
>or you could stack 3 pieces of 1-1/4 inch diameter fencing,
>with insulated guys.
>
>See the ARRL Antenna Book or Handbook for illustrations.
>
>Another good antenna is a vertically polarized Delta Loop,
>fed 1/4 WL down from the apex.  (Corner feed will work but
>has a tilted orientation).  Total Length = 1005 / F (MHz).
>If the bottom wire is close to the ground, you will need to
>shorten this by about 3%.  Feed impedance is around 100
>ohms which can be matched using a 1/4 WL (electrical)
>75 ohm line (RG59) which comes to 46.6 ft on 40M or
>(23.3 ft on 20M) if you use solid dielectric coax
>(velocity factor 0.66).
>
>With the high level of solar activity, 20M should also
>be open most, if not all, of the night.
>
>The MFJ 1793 vertical covers 80, 40, and 20 Meters,
>standing around 35 ft tall.  It requires radials and
>insulated guys.  Price is around $160.  It is a good
>design, both electrically and mechanically.
>
>Tom  N4KG
>
>
>
>
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List Sponsored by AN Wireless:  AN Wireless handles Rohn tower systems,
Trylon Titan towers, coax, hardline and more. Also check out our self
supporting towers up to 100 feet for under $1500!!  http://www.anwireless.com

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