When designing a low band antenna for my Guam QTH, I purposely went
through great trouble to make a true "TEE" vertical to avoid having an
inverted L on 160. I figured that being limited to 55ft of vertical
height, the rest of the "L" would present a significant higher angle
horizontally polarized component. I am located 1,500 miles from Japan
and 7,000 miles from both Eastern North America and Western Europe. I
wanted to maximize low angle takeoff and efficiency by using top loading
and a good radial field, and to keep the radiating portion centered as
much as possible over my radials.
I understand that high angle propagation does occur on 160m, however low
angle generally rules. With room for only one transmit antenna, I felt
it was more important to be prepared for the 90% scenario, instead of
those rare occasions when high angle takeoff is a factor. I think those
who worked me for a new one and those who still need Guam on 160m will
thank me for the decision I made. By all means, if you have room for
more than one antenna, a second high angle radiator could be the trick
to completing some QSOs. However, if you only have room for one, I'd
aim to have a radiator as high in efficiency with as low an angle of
takeoff as possible. This is what you get with a vertical over salt
water, usually considered "the ideal situation".
73, Dave KH2/N2NL
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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