Hi Don,
During the winter season, I install 2 Beverages - a 600 ft one to EU,
and a 400 Ft West Beverage. They work VERY well on 160, pretty
well on 80, once in a while useful on 40 (during storms), and
useless for higher bands.
I've never used one in CQWW RTTY only because the field I run the
wires across still has corn planted in Sept (bummer!) It's an anuual
ritual for me in November, though
Best book on the subject is ON4UN's book on low band DXing. To
sum it up in a nutshell, you need a ~450 ohm load on the far end
(from wire to ground) and a 9:1 transformer on the close end to
which you connect your coax. It would be better a little higher, like
6-10 ft for 2 reasons:
First, if any people or animals happen by, it's better above their
heads. Second, the impedance changes as you go up or down (I
forget which way it goes) and you may need to modify your load
and transformer.
They say Beverages work best over poor ground, so your swamp
may not be ideal, but better than nothing. I use Beverage
transfomers from ICE. They are also available from other sources
(K1FZ for one).
If you need any other info, drop me a line. It may also be helpful to
review the archives of the Top Band reflector. I'm sure this subject
has been discussed ad nauseum.
Also, with SO2R (is that a dirty word here?), I use a bandpass filter
on my Beverages to prevent overload of radio 2 (listening on
Beverage) while radio 1 is xmtg.
73,
Barry W2UP
On 6 Sep 01, Hill, Don wrote:
> Sorry if this is a little off-topic, but for this year's CQWW RTTY DX
> Contest,
> I would like to use a better receiving antenna for 80M.
>
> I have received several reports from stations in EU that I have a decent
> 80M signal when I am low power (approx. 80W output to an inverted V with
> apex at 60 ft.) So my little homebrew wire antenna seems to transmit
> fine, but it does not receive well.
>
> Behind my house, someone cleared out all the trees in a very big stretch
> of land (probably about 2 miles by 1/2" mile swath). I think one day they
> will
> build a road back there, but for now it's nothing but swamp land with weeds
> 4' high in mud and swamp water.
>
> I've read about beverage antennas and still don't understand them, but I
> was wondering if I ran say, 500' of wire out into this swamp and somehow
> elevated it 3 or 4' off the ground, would it be a very good receive antenna
> for 80 meters?
>
> Could I just run some RG8 coax to edge of my land, terminate the shield
> to a ground rod and connect the center conductor to the 500' of wire, would
> that work OK?
>
> The problem I have is that I only want to make one trip, and one trip only,
> into that swamp. Luckily I have my waders out for next weekend's
> opening of Teal Season, but with the possibilities of snakes and alligators
> in the lurks, I dread going out there at all.
>
> Any suggestions?
>
> Thanks, Don AA5AU
>
>
>
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--
Barry Kutner, W2UP Internet: w2up@mindspring.com
Newtown, PA Frankford Radio Club
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