At 05:27 PM 5/8/97 +0200, you wrote:
>Hi there
>Has anyone experience with XQ quad ( 2 wave loops)
>Is their gain really a sgood s they claim
>Is bandwith still ok?
>I'm looking at XQ quads from MGS, really impressive gain figures on
>paper..
>Any input welcome
>73
Extended quads were the rage in the early 70's. I remember KV4AD (now
PJ8AD) had good results, but not much since then. They are related to the
bi-square which G2PU used for years.
I think the gain figures were overdone on all antennas. Some were just a
guess (every 3 el tri-band beam did not have 8DB gain), some done on a
testing range but fudged up, some compared to a dipole at the same height.
Unfortunately there has been no standard. N4KG gave a good talk about earth
gain and height in a summation moment( he had a nice chart for support).
Force 12 comparison gain figures are very good for comparing one of their
products to another, but not to competing products. KLM with the KT
34/KT34XA was the first to put charts in the manual for both gain and FB and
these are for perfect set ups (few have the KT34XA perfectly set up). If
anyone believed the figures that W3/VK was pushing for a 3 el 20 on a 12'
boom or that 2el driven beam series
I have a bridge near Brooklyn to sell..cheap!
A quad has some gain over a dipole depending on configuaration of the loop
(2 dbd for a circle to less than 1.5DB for one with odd sides etc). The
Bi-square has been quoted as having nearly 4 db (d or i was the question)
I remember one study (before the modeling programs which still have problems
with loaded beams and odd wires) that said realistically a 2el XQ was a db
or so better than a quad.
MGS should have the fiberglas to at least keep it up there in the weather.
Dave K4JRB
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