[TowerTalk] Shortened Elevated Radial Articles

[Dennis W0JX]

To All:I apologize for not providing the reference to the Dick Weber K5IU article on the subject of shortened elevated radials.
Here are the references:
"Optimal Elevated Radial Vertical Antennas" by Dick Weber, K5IU. COMMUNICATIONS QUARTERLY, Spring 1997, pp 9-27.
"Modifying a 160 Meter Elevated Radial Vertical" by Duane Walker, KE7BT, COMMUNICATIONS QUARTERLY, Summer, 1998, pp 19-28.
Also, Les Moxon, G6XN wrote about this topic in Chapter 4, pp 43-45, of his very useful book, "HF Antennas for All Locations."  (RSGB 1982)
In summary, 1/4 wave radials may not be the optimal arrangement for your particular antenna system depending upon many factors. Dick Weber's work suggests that for shortened radials, 60 degree radials (approximately 67% the length of a 1/4 wavelwength) is an optimum length. Shorter than that and efficiency drops and bandwidth narrows significantly.
Measuring your radial currents with either an MFJ current meter or a homebuilt test set is a good way to check your radial currents. Incidentally, using a current meter on your ground radials is also worthwhile to check their effectiveness.
If any one wants a copy of the above Communications Quarterly articles, I will be happy to email them to you.
73, Dennis W0JXMilan, OH