> > 1. for 80m phased verticals that are 1/2 wave apart (66 feet),
That is 1/4 wave separation - not half-wave. One half wave on 80 is
roughly 139 feet (984/3.55/2 = 138.6 feet).
Since you are using 1/4 wave spacing and a PVS-2 (which is a quadrature
device if I remember correctly), two /14 wave cables (about 54' each
when the velocity factor for foam is included) should *easily* reach
the midpoint of the array.
73,
... Joe, W4TV
On 11/17/2012 6:56 PM, DALE LONG wrote:
Until recently, I had phased verticals on both 80m and 160m and lots of
beverages. (this was in a woods, and not my property) Then the loggers came
and destroyed all.
In addition to the antennas, the phasing lines were torn up, and broken and
needed replacement. For 160m I use the Christman method with .71 and .84
wavelength lines. For 80m I use a Comtek PVS-2 controller.
In replacing the 80m phasing lines today I made a stupid mistake, I dont know
what I was thinking, but I carefully measured and soldered two identical 1/4
wave lengths of new coax. I tested them on my AIM 4170 and they were nearly
identical, exactly on the design frequency. Then I went to install them and
guess what...of course they were too short. I have worked with phased
verticals before and I know that you often need to use 3/4 wave phasing lines,
but I was too intent on measuring and soldering and making the repairs.
So now I have two questions.
1. for 80m phased verticals that are 1/2 wave apart (66 feet), what will be the
pattern? It's not the same as 1/4 wave spacing, so what really is happening?
2. what is the best length of phasing line to use. Should I use 3/4 wave
phasing lines? Should I avoid using 1/2 wave phasing lines?
Thanks
Dale - N3BNA
_______________________________________________
Topband reflector - topband@contesting.com
_______________________________________________
Topband reflector - topband@contesting.com
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