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 phased verticals 
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Post phased verticals
I am new to this site/forum so go easy on me.

I have been thinking for some time about mounting 2 phased verticals on my narrow boat, 32 foot apart 1/4 waves for 40 metres. I already use one 1/4 against the hull of the boat and its works very well. I just use a fishing pole with wire in it and its cut for 40 metres. Even though fresh water is not all that conductive compared with salt water it would seem that combined with the steel hull the aerial does work well and possibly does not suffer the 3db loss of a normally ground mounted verticals? My question to those out there is, do you think that two phased verticals is worth trying? Most of the designs i have seen use elevated radials and therefore differ from my suggestion somewhat. My thinking is that gain is gain and useful regardless of overall theoretical ground losses. Hope this made sense


Dan

G7GRO


Thu May 28, 2015 6:17 pm
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 phased verticals 
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Post Re: phased verticals
Dan,

You could get some useful gain with the right phasing between the verticals.

EZNEC shows a maximum of 4.6dB gain at low elevation angles over a single vertical - 3dB might be more likely in practice. The lobe is end-fire to the line joining the verticals, and the relative phasing needs to be around 150 degrees.

You can't do so well broadside - only about 1dB advantage over the single vertical.

As ever, achieving the correct phasing will be the challenge - particularly if the feedpoint impedance is not well-defined because of the ground you are using.

Steve G3TXQ


Thu May 28, 2015 8:50 pm
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