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Hi Bob that soundsa terrific location for Europe
sloping away to the East, and it sounds like your ground is helpful too. It is
interesting the well helps though not as much as hoped for......this is the sort
of thing I mean by diminishing returns. One thought which may not be helpful is
that with a "T" the highest voltage point is then of the top-load, So the
maximum return current is collected underneathe the ends ( from a paper in
1926 about the Naun LF station in Germany) that is the point where the
earth mat is most effective. I am guessing from your description that the
chicken wire covers that region.
As you were mentioning high RFvoltages...... This
is perhaps where inductive to loading would help as it reduces the voltageat the
feed point. The problem is it would not help with your 80m and 160m
transmissions :-))
Just I quick thought....I assume from 80m etc use,
the top runs N<>S ?? This would probably be the best for Europe on 73
because an E<>W sloping top would throw most of the signal at a
higher angle in the direction of the top run....to Europe.
Interestingly I think you are geting reception to
the south this may be skywave or a mixture. Skywave seems to predominate beyond
700km say 500miles. I think you said the reports were from
300miles.
One of our problems was that we were alone in the
UK for a lot of the time we had 73k and 300m would cover most of the active
stations maybe 12 or 15 at most.
I am thinking that with a following wind on a good
night you should be copied in Europe. QRSS is easy to generate but is not always
the easiest to identify if it gets chopped up. Also most of the "artifacts"
produced in the receiver and local to the receiver can look like weak QRSS
I always found a sheduled frequency move (very small) much easier to spot
visually and it is why DFCW became so popular (dots and dashes on
different frequencies and no character gaps... only letter and word gaps ....of
course with separation the dots and dashes can become the same length. ..shifts
were often a few tenths of a Hz) It speeds up the transmission a
bit.
Good Luck
Alan
G3NYK. .
----- Original Message -----
Sent: Wednesday, September 25, 2013 8:13
PM
Subject: RE: LF: TA CW?
Stefan; The voltage is terrible! I can draw a 2.5 inch
flame off the ant input. I am cramped for space to the west as I am only
20 feet from the neighbors line. I am on 4 acre lot and room in all
but that one direction. More top loading would be great but also use
this ant for 80 and 160 meters. I have seen the 700' Loran C tower up
close and it uses the three top guys as top loading. It used to wipe out
all but the 500 kHz band here. I could use 185 and did for awhile
because 137 had terrible splatter from that signal. You can go to google
maps and get a real good shot of this place. Last I looked the
tower shows up and house with cars in driveway even. If not I can take
couple pix for you. coordinates "NL 42-40-05 ; WL 77-04-28"
You are probably using a much bigger ant than what I have here. A
couple hundred footer would sure help for 137/73-Bob
Date: Wed, 25 Sep 2013 15:21:20 +0200 From:
[email protected]To:
[email protected]Subject: Re: LF: TA CW? Hi Bob,
Am 25.09.2013 03:01, schrieb Bob Raide:
[...]But only have a 90' high tower and at the top is the
center feed point of my 75 meter double extended zepp. I simply short
the open wire line which runs almost vertically and fed it with allot
of inductance in series! I assume the two 150' legs acts as top
loading. Ground system is from my broadcast experience where for field
intensity surveys 36" wide chicken wire was used with a 100' tower most
often and a 250 transmitter. Eight 50' chicken wire radials
produced decent field on the midband channels [1000 kHz or so] to
measure from. Here I am using several 150' radials of chicken wire
radials. I hope to stretch some out to 300' but that's going to be
about it at my location.
Can you post a link to
some photos showing the tower and environment ? Do you use deep earth
rods additionally to the wire radials? Can you add even more capacitive load
to the top of the tower, giving an umbrella antenna. 600 pF, as Alan sais, is
nice but not much on 73 kHz and you seem to be voltage limited now (like me,
sometimes :-) ). Some images would be interesting for us i
think. 73, Stefan/DK7FC
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