Gerry,
I was flying blind, sort of speak, by the seat of my pants, building this
vertical and pieced together things I had picked up discussing antennas with
other hams so don't feel bad about not getting how it was assembled. I made
the vertical antenna in two pieces in order to climb up to the roof on my
tower bolted to the back of the house. The antenna was bolted to the other
end of the roof so I could get right to it as needed for fine tuning. Right
about roof level, the first section stuck up, therefore about a foot or two
over the peak of the roof. The second section of antenna was made up of
three parts. Two pieces of tubing, one short and one longer, and between
the two was a coil form with wire wrapped around it. It was insulated wire
and I used about three feet of PVC tubing as my coil form. The longer piece
of tubing that served as the bottom of the assembly, I think it was 7 feet
of aluminum tubing, I stuck up inside the bottom of the PVC pipe the wire
was wound around, or coiled, around. It was wrapped closely, like a bull
constrictor snake, because the wire, as I mentioned, was insulated and I was
only running 100 watts. So that insured there would be no arking when
transmitting. If you run higher levels of power, it is best to use coax,
the heavier the better, based upon the power, because the voltage is very
high on the coil when transmitting. Next, I took another 3 foot length of
aluminum tubing and stuck it inside the top of the pvc pipe. The pvc pipe
was big enough so I could drill into the tubing and the pvc pipe to hold the
bottom tubing and the top tubing to the pipe or coil of wire. This is all
vertical so far. The signal, therefore, had to pass through the coil before
getting above the pvc pipe to the top hat, which was the difference between
32 and about 130 feet; which is a quarter wave on 160 meters. About 98 feet
of coil wire in other words. The horizontal part of the top hat is also
aluminum tubing whereby I used simple hardware clamps to clamp them in the
shape of the letter X at the top of everything, that is, at the very tip of
the tubing. The reason I made the whole top assembly separate, was so I
could climb the roof, walk over to the vertical clamped to the end of the
peak of the roof, and loosen another clamp which held the whole top assembly
in place. Once I put the X on top, I didn't have to raise or lower the top
assembly more than once or twice to get the antenna to resonate where I
wanted it in the CW portion of 160 meters. It was fun making it, I learned
a lot, and from that time on, when I put up a bigger tower that same year
but in this house we bought that year, I really got into all kinds of wires
and loops and shunt feeding my tower, and trying phased verticals and wire
antennas.
Phil.
K0NX
----- Original Message -----
From: "Gerry Learry" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, December 05, 2012 7:53 PM
Subject: Re: A SHORT VERTICAL FOR THE TOP BAND
>I don't understand how it is assembled or connected to the top of the
> antenna. I understand that the two elements are in a X pattern and they
> are
> both horizontal, but I don't understand the mechanics.
> ----- Original Message -----
> From: "Phil Scovell" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Tuesday, December 04, 2012 1:50 PM
> Subject: Re: A SHORT VERTICAL FOR THE TOP BAND
>
>
>> Gerry,
>>
>> What specifically were you asking about as far as the capacity hat is
>> concerned?
>>
>> Phil.
>> K0NX
>>
>>
>>
>>
>> ----- Original Message -----
>> From: "Gerry Learry" <[log in to unmask]>
>> To: <[log in to unmask]>
>> Sent: Tuesday, December 04, 2012 3:39 AM
>> Subject: Re: A SHORT VERTICAL FOR THE TOP BAND
>>
>>
>>> Can you describe the construction of the top hat a little more?
>
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