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R Alan,
Down to one of Mr Hobson's fine
designs here , the under slung wire ,
would be the simplest to arrange , say
it ran 10 ft above a 90 ft
elevated ground radial , now would
that xtra C , increase the amp's in the
vertical section , the other side of the
top coil ...?
Other wise its ,just possible to run 90
deg about 20 feet , 90 then down , at
the far end
I tune using a swr meter , usually get a
sharp dip with the variometer , but I
also have a old 1000 pf 4 gang
clipped , low over the auto transformer , that is handy
, just takes the final 'ref down and
as its low , there is no flash over , bit
like a band-spread on a rx oscillator coil
Testing wise , luckily , I can reach the Delft
web-sdr in the day time , so can
do s/n checks at range using
ROS-MF-2 , the s/n is the average
along the time line , so quite accurate
Still raining
73 -G..
Sent: Thursday, June 21, 2012 8:59 PM
Subject: Re: LF: Re: InV L Top wire config - Best Option
??
Hi Graham its not exactlyaerial weather here either
:-((
The problem with unconventional "shapes" is you
will have to just try 'em out. I have always concentrated on reducing ground
loss as the most effective use of time and effort. Best done by measurement,
and not urban myths :-)) Thats why I always plug a simple transformer
coupled bridge, oscillator and receiver as a detector, noise bridges have never
worked at LF for me ....probably too many BC stations close by. I also like
bridge measurements......its probably an "age thing" :-)) I feel closer to
the problem and able to employ some skill and maybe dexterity, even if I dont
get the numbers on the readout of a VNA......at least I learnt to sense when the
measurement "feels" right. It is the classic substitution measurement with
passive references.
Alan
G3NYK
----- Original Message -----
Sent: Thursday, June 21, 2012 6:48
PM
Subject: Re: LF: Re: InV L Top wire
config - Best Option ??
R Alan.
Horizontal spread ......missing at the moment
... will have another look out side
, when the rain stops , horizontal open
box may be possible ..just
Tnx -G..
Sent: Thursday, June 21, 2012 4:42 PM
Subject: LF: Re: InV L Top wire config - Best Option
??
Hi Graham it basically doesnt matter too
much :-))
The thing is to get as much wire as high as
possible. Yes fold it back, meander it....spacings less than about 2 feet dont
add much over a single wire. Drop the end if you have to but remember this may
reduce the signal slightly in that direction....but it will increase slightly
the capacity to ground. be careful of the dropped ends they are high voltage
points and may not be "family friendly" ...... doubling the capacity to
ground ( note ground....not lossy roofs/foliage underneath) will probably
halve you ground losses. It will do very little to increase the radiation
resistance.
Your diagram is difficult to read but running one
of the wires directly under another will be of no benefit and may be worse
than not having it......horizonltal spread is what you want, so pull it at
least 2 feet aside before folding it back.......I think you get the
idea.
Alan
G3NYK
----- Original Message -----
Sent: Thursday, June 21, 2012 4:17
PM
Subject: LF: InV L Top wire config -
Best Option ??
InV L Top wire config - Best Option
??
Any thoughts on the best configuration for
the top wire ??
Tnx -G,
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