Practical_Antenna_Handbook_0071639586

C h a p t e r 1 7 : E m e r g e n c y a n d P o r t a b l e A n t e n n a s 395
Wire antenna
Mast
Insulator
Rope
Holder
(see text)
Figure 17.3 Portable inverted-vee antenna.
to 160 ft makes a pretty good run for 160 m, and a total length of 70 to 100 ft should
work well for 80 m. This is an inverted-L, which is a very efficient cousin to a conventional
l/4 monopole; its radiation and matching characteristics are covered in detail in
Chap. 18, but its advantage here is that it’s very simple to erect, and it provides a mix of
high-angle and low-angle radiation from a single antenna. Note: For proper operation,
the inverted-L must have radials, a counterpoise, or a tuned RF ground (see Chap.15) at
the feedpoint!
Almost without fail, all of these portable antennas will outperform the basic mobile
whip installation. Because the application is both emergency-related and temporary in
nature, we can get away with installation and support techniques that would be unthinkable
in more permanent installations. But it is absolutely imperative to have an
antenna tuner and VSWR monitor to properly set them up.
Temporary Supports
Anyone serious about being prepared for emergency or portable radio operation will
very quickly develop an extensive list of “must have” items. The extent of the list will