When I sent out a recent email about the 160m inverted-L I was finishing
with four ¼ wavelength (130?) radials, I got a few responses back indicating
that I should cut them in half and double them.
So I got out ON4UN?s book to look at the guidance there.
· Chart 9-18 on p. 9-12 indicate that the radial lengths should be
10m, 40m, and 80m (basically, that?s 32?, 130?, and 260? w/rounding).
There?s no mention of 20m (65?) radials in these models.
· Table 9.3 on p 9-14 indicate that for four radials, the optimum
length is 0.10 wavelength (about 51?) and 0.15 wavelength (about 76?) for
twelve radials.
· Then again, the text in section 2.1.3 on p 9-14 says ?on 160
meters, you should use 20-meter (65?) radials if you are only using a few
(up to four).
Overall, I?m considering going with the design suggestions in table 9-3 for
twelve radials (30-degrees apart) that are 76.7? long (0.15 wavelength for
1.83 Mhz).
Any opinions about that?
Mike, WA9PIE
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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