Bill,
You neglected to say what was on TOP of the tower.
Hopefully you have some Yagi or dipole top loading the pole.
Second, without knowing the IMPEDANCE at the end
of the matching wire, it is impossible to guess how to
match it. Which MFJ antenna analyzer do you have?
IF you know the resistance, and it is less than 50 ohms,
then you should add a second capacitor from the matching
wire to ground, forming an OMEGA match. This will raise
the feed impedance at the coax, assuming the other capacitor
is between the matching wire and the center of the coax.
73 / GL, Tom N4KG
On Wed, 5 Dec 2001 " <w9ol@billnjudy.com> writes:
>
> First off I have a old Wilson rotatable crankup.
> On the mast, I installed a guy ring type bearing with a horizontal
> aluminum
> tube.
> One end supports the middle of my 80 meter dipole. Other end
> supports
> vertical wire for 160.
> This way the tower can rotate and the dipole and the vertical 160
> wire
> remain stationary.
> The wire is attached to the tube at 24" from the tower, which was
> the
> dimension in on4un's book.
> The wire is approx. 50 feet to the ground.
> Braid to tower ground/earth ground/radials.
> Center conductor to variable caps. and to wire.
>
> Best I can get using a MFJ is 3 to 1 and it fluctuates with the wind
> blowing
> the wire slightly.
>
> What is the best approach, move the wire closer to the tower or try
> more/less caps?
>
> Using the graphs in N4BA old article I should be pretty close on
> dimensions.
>
> Anyone see any obvious errors?
>
>
> ------------------------------------------------------------
> My wife dresses to kill. She cooks the same way.
> ------------------------------------------------------------
>
> Bill H. in Chicagoland
> w9ol@billnjudy.com
>
>
>
> List Sponsored by AN Wireless: AN Wireless handles Rohn tower
> systems,
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>
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>
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