Hallo Andre!
>seems I am lucky in next winter. It looks like
I will get the ok for renting neighbours
horseground for cheap (mmmh.... cheap?....) during the dark months. Thats the
moment I am waiting for years now.
You are indeed very lucky! Having lived in Germany
for 2 years I know how expensive land is and how lucky you
are. Take your time on this project as it will be lots of
fun and pay huge dividends if you do it right. Every QTH
I've had (3 separate ones now) has its unique advantages
and disadvantages. The challenge is always fun to find
the way to maximize what you have.
>I have read a lot last hours, specially the
"low-band-bible" and Tom´s, W8JI Site.
According to that special hints I tried to fill
that acre with a wire web, which hopefully will
work, but I am not sure.
I tried to cover all main directions, depend on
distance. I also tried to face the Ant-angle
vs. length.
You are using the correct references (ON4UN's book
and W8JI's website). No need to read anything else!
>What is your experience, has someone tried such an Bev.-park b4?
- Fx (light blue) are Feed-Points for the Bevs
- deg and Area added, for DL
- possible length of Beverage below
I have not operated Topband from Europe and
others in EU may have better experience, but here are my
comments:
1. I would make F4 bidirectional. The reason for this
is to catch long-path openings to the Pacific at your
sunrise. The path to Pacific from Europe is equivalent
to our path to SE/Central Asia from NA. These skewed
signals are more often SW just before our sunrise rather
than the direct bearing which must cross the magnetic
North Pole. From here, the path is often more south (SSW)
than your diagram, but 225 degrees should still work OK.
2. You have correctly made F5 bidirectional to catch
long-path openings to the SSE at your sunset.
3. Northern hemisphere signals are often skewed South
during Auroral disturbances. F3 (West) will work well
for NA, and F3 (East) for JA in these conditions.
> I respected Tom´s experience, Feedpoints (with
ground-rods) several wire-heights
seperated. Bevs. will be 1 to 1.5m agl, Feedpoints more than 10m separated.
You are lucky that this is apparently a fenced
pasture for horses, so you don't have to worry about
animals (deer or humans). I would use 1m high if you
are sure it will be safe. I've found 1m Beverages work
extremely well compared to 2m high, but be absolutely
certain not to endanger people. I also have used
multiple Beverages to the same feedpoint at every one
of my QTHs. If this would help minimize feedline cost,
be sure unused Beverages are disconnected at the
feedpoint and grounded through the termination resistor
at the far end. I've never used bidirectional Beverages
but my experience is that unidirectional Beverages do
not interact if you follow the above rules. Someone
who has experience with bidirectional Beverages may
have comments.
> On Crossing points (especially between
F2/F5/F6 and F2/F4) the wires will be >0.3m
(1ft) apart others (Tom´s Site)
Correct. No problems.
> Still not sure abt the wire I will use, here
are some animals. Wire should be strong.
Might be another question.
I have used electric fence wire for animals.
It is very strong and lightweight. Here we have both
galvanized wire (heavier) and aluminum wire (light).
Both require special consideration for connections. I
use electrical twist-on connectors with Noalox paste
inside the connector. This is probably not a good
long-term connection but works OK for 6 months which
covers the winter season they are up each year. I
actually prefer the aluminum wire but you must be
very careful not to kink it or it will break. Galvanized
is much more durable but needs more interim supports due
to its weight.
> Soil is wet here, the first ground-water
always (!) between 1m and 1.5m below ground
level.
I'm sure you know good conductivity is not
good for Beverages, but you must use what you have.
> Ground-Rods will be 1.5m long copper
With your ground you could probably use
shorter ones. Many of mine are only 1m and I
install and remove them each season.
> Coax will be Belden 9907 (that one which is
similar to RG58), longest run 200m.
Why not use RG-6 75 ohm? It is much
less expensive than 9907. Here we can buy it
for around EU 0.10 per meter. Be sure to get
flooded cable if you bury it, but perhaps you
will just lay it on the ground and wind it
up each season (as I do with some of mine).
>Questions are, for 80m and 160m:
>1. Will that rx-web work without interaction?
Looks OK to me. You may also want to
use decoupling ferrite beads on your feedlines as
Tom describes on his website.
>2. Will that work with my Tx-Vertical, or
should I ground/flow some in case of rx/tx?
Always safer to ground it, but you might
try experimenting first. While listening on all
Beverages, ground and unground the tower to see if
you hear the RX noise level change. If you do, you
have some interaction and should ground during RX.
>3. Do I miss some basic in my ideas, maybe
easier or impssible ways to use that 2
Hektar for rx?
Looks very good to me, but you also probably
have room for one of the small 4-square RX arrays
if you want to try that also. You might also want
to consider end-fire phased Beverages for some key
directions where you need maximum F/R (maybe not
necessary for DX-ing but helpful in contests).
Have fun and enjoy a new world of RX performance!
73, Bill W4ZV
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