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 ON4UNs 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, thats 32, 130, and 260 w/rounding). Theres 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, Im 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 _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? BK
