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Antennas at W5UC 160 Meters: After using a shunt fed tower for several years I decided to try a Inverted L antenna. Wow! This is a great small lot antenna, and significantly out performs the Shunt Fed tower. The support point is at 65 feet and has been pulled up the tower with a rope & pulley mounted on a 3 foot horizontal piece of aluminum at the 65 foot level. The antenna is #14 stranded, plastic coated house wire which is NOT tied to the insulator that is used to pull the antenna up the tower. Rather, the wire is allowed to slip through the insulator making it easy to adjust the tension on both legs of the antenna from the end point of the horizontal portion. The horizontal portion slopes down to approximately 40 feet elevation and is supported by a tree in the front yard. It is fed using a T Network at the base. Most publications put the feed impedance of this antenna close to 50 ohms. However, EZ-Nec calculated the feed impedance at around 5 ohms, and that turned out to be correct; thus the need for the T network. Antenna pictures
For 160 Meters I also have a modified K9AY receiving array. Go to 160 Meters for pictures and a detailed description.
80 Meters: For several years I have been using a full wave Delta Loop on 80, and so far have found no reason to change. The apex is supported, again by a pulley & rope at 65 feet, on the opposite side of the tower from the 160 meter Inverted L. The antenna is resonant at around 3510 kHz, and the feed point impedence provides a good match at around 1.2:1. The feed point is approximately 10% up one of the "top" wires of the antenna. My interpretation of the information in "Low Band DX'ing by ON4UN indicates that this is the best feed point for low angle radiation. The antenna performs as well as can be expected in an environment consisting of numerous very tall pine trees and one very large Oak tree near by. It is my belief that it would be an above average antenna if it were out in the open. Still, it allows me to be somewhat competitive in this less than ideal location.
40 Meters: Another favorite at W5UC. This is a 1/2 wave sloping dipole supported at the upper end by the same rope & pulley that support the Inverted L. The tower influences the pattern of this antenna and it is oriented such that it gives a small amount of gain, probably less than 3 dB, toward Europe.
30 Meters: My pride and joy. On 30 meters I run a full size 2 Element Yagi at 70 feet. Calculated gain is around 4.5 dBd with a F/B at 10.5 dB. This antenna that I designed and built survived the 90 MPH winds of Hurricane Rita, as did all of my antennas. Nothing more to say except that it makes me very competitive on 30 meters.
20, 15 & 10 Meters: Another old & reliable antenna. A Cushcraft A3 that I have been using since 1987. It still works well enough to work the VU4.
6 Meters: I started on 6 meters with a 3 Element Yagi that I designed and built. Calculated gain, according to EZ-Nec, was 6 dBd. It performed well, but last year was replaced by another 6 meter antenna of my design. It is 6 elements on a 21 foot boom with calculated gain at 10.5 dBd. Feedline is 7/8" Heliax. The 6 meter antenna was not on the tower when the pictures were made. It replaced the 432 mHz yagi shown just above the 30 meter yagi in the pictures of the tower mounted antennas.
The new 6 Element antenna went up the tower on 7/9/06. It is a winner. It tuned up exactly as predicted by the software. F/B is great, and the side lobes appear to be very clean. I worked numerous stateside stations and 6 countries in the CQ VHF contest.
2 Meter terrestrial: A Cushcraft 4218XL at 80 feet. Feedline is 7/8" Heliax. It has been around a while, but still performs well.
2 Meter EME: This antenna is 56 elements of collinear consisting of 2 bays of 28 elements, with 16 dBd of calculated gain. Originally, each of the bays was 20 elements of the old Cushcraft 20 element collinear. Additional directors were added to each of the original antenna bays. The result was to clean up the pattern and increase the gain. The EME array is mounted on an 18 foot tower and is shown in the first 3 pictures on the antenna picture page. Antenna pictures
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