Kurt N. Sterba Memorial Antenna Comments
...or "Why'd they publish that?"

This page is dedicated to that great bastion of rationality and common sense, Kurt N. Sterba by nom de plume, who, in his column in "WorldRadio" magazine, has debunked many of the myths associated with antennas and transmission lines. Who this Masked Man is, we shall probably never know, but his service to mankind is unquestionably ... boy, is this getting deep ... without equal.

I hope the comments on this page are worthy of a nod of approval from this great man ... and very few hoots and hollers of disdain.

Articles and Comments

1998

CQ Amateur Radio, July, p. 20
"How to Build an Effective All-Band Counterpoise"

The article describes a multi-band counterpoise, a ground radial, that could also be used as a vertical radiator or as half a dipole. It is made of 300 ohm twinlead, with one wire cut to the lowest band, and one wire cut to a higher band, and a stub attached to the end of the longer wire to give a resonance on a still higher band. It uses the line's velocity factor and includes an end-effect factor. I don't understand this structure.

First, velocity factor only matters for transmission lines, not radiators. I know a dielectric will affect the velocity on a radiator. Is this just a coicidence? And the ARRL Antenna Handbook says a multi-wire dipole has a large interaction because the wires are close together. WB9SKE and K9PPW have both tried to get the "multi-wire" structure tuned, and failed. If things were this straightforward, then sleeve monopoles, etc., wouldn't work. I don't understand. Maybe he knows something we don't.

CQ Amateur Radio, July, p. 28
"A Closer Look at the Extended Double Zepp"

As the title implies, the article talks about EDZs and tells how to design one. Note that the G5RV antenna is an EDZ for 20 meters, at 51 feet on a side, that can be used on several bands with a tuner. An EDZ is not a secret. An EDZ is just what others would call a "five-eighths wavelength vertical", but here balanced as a dipole, not over ground as a vertical. Also the comment that the feedline matcher can change the radiation pattern is just wrong. Not if the feedline isn't part of the antenna and doesn't radiate. And doesn't the matcher length depend on its velocity factor and the antenna's impedance, which depends on its height above ground? Or are we just compromising for several bands?