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TopBand: inverted vee, ladder line fed

To: <topband@contesting.com>
Subject: TopBand: inverted vee, ladder line fed
From: w8ji.tom@MCIONE.com (w8ji.tom)
Date: Fri, 30 Oct 1998 18:44:12 -0500
Hi Bill

> purchase some coax. Has anyone had any luck using ladderline to feed an
> inverted vee, or should i use a coax feed line?

If you have a good 160 tuner, you could use ladder line. Avoid feedline
lengths between 110-150 feet. I use ladder line on many of my antennas, it
works quite well. For high power, especially if you don't have a good 160
tuner, coax might be better.

Even though not as good as "real" open wire line, ladder line has less loss
than coax and also allows the inverted V to be used on other bands with
decent efficiency.

My new tower will be fed via 1400 feet of open wire line. That 1400 foot
long feeder has a measured loss  almost exactly equal to 100 feet of
RG-213/U!  It looses one watt out of every 25 watts on 160, and that
includes matching transformer losses. 

 also, any advice on spacing
> of the legs of the vee, say 90 degrees, less or more??  What happens if
the
> Vee legs are close together say 45degrees, with a forward attitude to
them.
> (like a sloper dipole)I have a small city lot, with many trees to dodge. 

In general you would be best off to keep the antenna in a straight line
with ends of the antenna as far above ground as possible, and the antenna
in the clearest spot possible. That will minimize losses. The effective
antenna height is lowered by Vee'ing the legs down, but since your antenna
is so low (anything below 150 ft HAT or so radiates mostly straight up
anyway) that won't make a big difference. Efficiency would be improved by
adding some sort of counterpoise below the antenna if you can.

>       Propagation question??  a month ago i would listen a lot to 1.823-1.840
cw
> each morning prior to sunrise. I would hear many really good local
stations
> working australia with apparent ease. I only use a 80 meter dipole to
> listen and work stations on 160. But I could not ever hear any of the CW
> replys from australia. But when the domestic station would call for a qsy
> from cw 1.832 to ssb and 1.840 i could copy the ssb signals from
australia!
> I really couldnt fiqure that situation out. I heard this many times with
> W8JI Tom. Does anyone else experience this. I thought cw would be the
> signal that i would copy.

Two things come to mind:

First, generally when I ask VK's to QSY, it is a few minutes after sunrise
here when signals are starting to fade. Since you are further west and were
using 
a makeshift 160 antenna, it is very likely you have a very narrow time
window when signals come through. You just might miss the earlier and later
propagation.

Bigger and higher antennas hear DX much longer on 160, verticals and
Beverages work better before the sunrise peak, a low horiz antenna can
really narrow up your "window of
opportunity" only allowing you to hear those signals in a narrow time
window.

Second, are you using a good CW filter and do you have good CW ears? Some
filters are too narrow, some too wide, some days I hear best with the SSB
filter on CW! I have poor SSB ears. Maybe you got the SSB gene I was
cheated out of?

Good luck and welcome to 160.

73 Tom

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