Topband: Fw: Top loading question.

[Magnus A]

Hello all!

I live on a very small lot, it is only 480m2 so getting up a fullsize ¼ wave
vertical on 160m is just to forgett, same with 80m.
I am lucky to be friends with my neighbours and the 3 most nearby neighbours
will actually let me bury some radials in their yard. (Lots of nice talking,
being friendly, invitations to grilling, beer and whiskey HI HI).

Anyhow.

I got my self settled on 80m but am now constructing a homemade vertical for
40m and 160m.
Lets see if I can explain it.

Fullsize ¼ wave on 40 (10,25m) put slighly over the ground.
After the aluminum tube for 40m I have 4,4 meter plastic tube so the height
is 14,65m for the construction.
At 10,2m height (near joint from aluminum to plastic) I have a cross bar
made of plasticsticking out 1,2m making the first part of the antenna to
look something like a T.
I am to put a wire from close to the feedpoint of the 40m antenna up to the
end of this plastic crossbar that is 1,2m out. From there I will take the
antennawire to the top of the structure and from there use a top-hat /
capasistance hat.

Now I figured my slightly sloping (in 2 directions) vertical will have a
lenght of 17,5 meters.

I will use 4 wires (can do more) for the top hat but they will be sloping
downwards quite steeply. in a few cases more then 45°.

The wire will be 5mm thick.

Can somone help me to figure out the lenghts I need?
Or direct me to somewhere were I can find the info.

PLEASE

73 Magnus SM6WET / 8S6T