[HCDX]: low-angle antennas
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[HCDX]: low-angle antennas

(response to recent hard-core-dx discussion)

I've had a couple of vertical and sloper experiences.
In 1975, when I rented a house at Sudbury, MA (about 30
km west of Boston) I had a 400 m Beverage towards Europe
and a 30 m vertical wire (pine tree supported).  At or
before sunset, on initial fade-ins, the vertical
actually brought in clearer low band European MW
stations (Daventry, UK on 647 was common in those
days).  Within an hour, the Beverage with its tighter
directional pattern became the superior antenna (since
it rejected increasing skip from stations to the west
as evening progressed).

More recently ... summer of 1999 to be exact ... my
family stayed a week at my brother-in-law's house in
East Harwich, MA on Cape Cod.  The house is about 3 km
inland.  A loop used right at the shore picks up
very impressive Canadian Maritime Provinces AM
stations on groundwave during the day and strong
Europeans (especially Spain) at local sunset.  The
performance of the small ferrite loop at the E. Harwich
house is far less impressive because the 3 km of sandy
soil between the house and the shore really eats up
signal strength on an antenna so close to the ground.
Just like Tom's area in NJ, the East Harwich house has
many pitch pine trees (indicators of sandy soil) near
it.  When I spend a few days there, I put up two slopers
of about 25 m each from the house to nearby trees.
One sloper is oriented for northeast pick-up (Europe)
and the other for southeast pick-up (Brazil, eastern
Caribbean).  These antennas provide excellent reception
in their respective directions, thoroughly beating
any ferrite or small air-core loop, especially at
local sunset when medium wave signals from Europe,
the Middle East, Africa, and eastern Brazil are just
starting to fade up.  Last July, the southeast sloper
brought me some sunset-period low-band Brazilians
that I have never heard from any other US location.
The Europe-oriented sloper provides reception quality
that a loop can only achieve if operated right at
the seaside.  Some of the better catches have been
Italy-900 overiding CKDH/other domestics and Qatar-954
over Spain.  

The E. Harwich slopers worked reasonably well straight
to the receiver or phasing unit.  To reduce electrical
noise, I tried 4:1 baluns with a sloper to one primary
side and a 100 m radial wire (lying on the ground and not
connected to mains earth) to the other primary side.
Coaxial cable to the receiving position came off balun 
transformer secondary windings.
When I really wanted to crush the domestic
interference, I connected the two slopers to inputs
of a phasing unit and dialled up nulls that put even
pesky New York stations like WBBR into the "mud" to
allow co-channel Latin American and adjacent channel
European / African DXing.

A vertical phased against a broadband loop is another
good solution for limited-space installations.

Two verticals spaced at about 50 m and sent to
a phasing unit can work well if local electrical
noise isn't too bad.

The above discussion, and the recent K9AY Loop
experiences by the Grayland, WA medium wave
DXpeditioners, show that good low angle pick-up
and directivity do not always require a Beverage

The Top-Band (160-m) ham forum on www.contesting.com
also discusses this subject in considerable detail.

Mark Connelly, WA1ION
e-mail: MarkWA1ION@xxxxxxxxxx
web: http://members.aol.com/MarkWA1ION/weblink.htm

On Wed, 10 May 2000 21:26:59 -0400, hard-core-dx@xxxxxxxxxxxxxxxx wrote:

>  Thanks for the tip..you mentioned this setup would be good for medium and
>  high angle signals..what short of a beverage could be used for low angle?
>  Patrick
>  ------------
>  Patrick, the 25m vertical wire into the top of a pitch pine tree is one
>  my best antennas, really shows off at twilight with the tilting
>  layers to the east (or west) of me.
>  ---
>  Thomas R. Sundstrom <trs@xxxxxxxx>
>  TRS Consultants <http://www.trsc.com>
>  PO Box 2275, Vincentown, NJ 08088-2275, USA
>  +1 609 859 2447 | Fax +1 609 859 3226
>  Contributing Editor, Radio Netherlands' Media Network
>  <http://www.rnw.nl/realradio/>
>  Contributing Editor, 'Radio & Communications'
>  <http://radiomag.com/>

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