When an array of vertical elements are placed one-quarter wavelength apart in a line and fed so each one is 90 degrees out of phase with the one before it, an end-fire pattern is produced. My 17m array has elements placed every 13'7". The theoretical gain for a 6 element array of this type is about 6 dBi at an elevation angle of 25 degrees and with a beamwidth of 75 degrees. The f/b ratio is 25 dB or better based on on-air testing. A random length of 52 ohm coax connects each end of each array to a coaxial switch (I use an Ameritron RCS-10) providing rotary coverage on four compass headings. The system is located at a distance of about 300' from the shack.

The phasing lines for these arrays are 52 ohm coax cut in electrical three-quarter wave lengths. My tests showed that cutting these by formula produced reasonably accurate results, but I used a MFJ-259B analyzer to get as close as possible. Make sure you do a good job putting the PL-259 connectors on the coax. Each element is fitted with a t-connector. The feed line, 52 ohm coax of any length, attaches to one side of the t-connector of the first element. The other side of the tee attaches to the phasing coax and leads to the next element. Each successive element is connected in a daisy chain. The open end of the tee on the last element is attached to another feedline. Both feedlines can be brought back to the shack or to a coax switch in the field. The array will have maximum gain in the direction of the first-fed element.

Actual on-air performance has been very good. DX contacts consistently give excellent reports and frequently state that my signal is the strongest or only one being heard. My experience has been that my reports are comparable to those of other hams using a typical tri-band beam at 65 feet.

Some hams believe that a vertical will not perform well if the station on the other end is horizontally polarized, but this is not true for DX work. Each time the signal bounces off the ionosphere the polarization is randomly shifted, so the signal arriving at the DX station has an unpredictable polarization. Noise is very low on these antennas, much lower than a single vertical.

This system is clearly not going to work well in a situation where the horizon is obstructed. A few trees will not cause too much trouble, but neighboring objects and structures should be considered. This antenna works well because it radiates at a low angle; if there's a mountain sticking up 20 degrees in front of the antenna it's probably not going to work very well. My QTH is on a fairly level hilltop and I have a good shot to the horizon in each direction, giving the radiation the chance to travel as far as possible before bouncing.