The tower and directional antennas at N5XU

N5XU now has more antennas in the air than at any other time in its history. The photo to the right shows the antennas currently on the club's west tower. The tower is 40' of bracketed Rohn 25G. It is attached to the roof by a concrete pier and is bracketed to the staircase on the penthouse at the 20' level. The mast is a ten foot steel mast designed specifically for radio towers.

At the bottom of the mast is our biggest antenna, a Force 12 C-4 multi-monoband beam. The C-4 is three mono-band yagi antennas (20M, 15M, and 10M) on a single boom, with a 40M dipole. The 20M, 15M, and 10M yagis all share a common, proprietary open-sleeve feed, which uses no traps. The 40M dipole has a separate feedline. The antenna is assembled entirely with rivets to reduce play and vibration. While it is not specifically designed for the WARC bands, it can be used on 17M and 12M with an antenna tuner.

The club station, facing west

Above the HF antenna are five VHF/UHF weak signal monoband antennas. At the bottom is a small side-mount that holds a 45-element loop yagi for 1296 MHz. The side mount holds the loop yagi about nine inches out from the mast. The feedline is a rotor loop of about 18' of RG-213/U going directly to the transverter, which is mounted inside a weather-proof box at the top of the tower. The feedline between the 1296MHz transverter and the 144 MHz IF radio in the shack is RG-213/U. Next, going upwards, is a Directive Systems DSFO432-25 432 MHz yagi antenna, based on the K1FO design, fed with 1/2" Anrews Heliax. Next is a Cushcraft 13B2, a 13-element yagi for 144 MHz, fed with RG-213/U flexible coax. Above that is a 13-element 222 MHz yagi, of unknown design and manufacture, fed with a run of Times Microwave LMR-400 semi-flexible coax. At the top is a Cushcraft 50S3 yagi for 50 MHz, fed with RG-213/U; it has only three elements, which is fairly modest compared to some other local six meter stations. All of the antenna feedline runs after the flexible rotor loops are around 80' in length.

Above the horizontally polarized antennas is a Butternut 144 MHz vertical. In the past, it has been mostly used with the packet radio for communicating with the local DX cluster. Two of its ground radials are shorter than they should be. Below the horizontally polarized antennas is the feed point for a fixed 30 meter inverted-V wire dipole. All of the antennas except for the wire dipole are on a single ten foot steel mast, and are rotated by a HAM CDE 3 rotor.

This is the tower that was put into place following the disastrous September, 1995 wind storm that blew down the previous tower. The new tower is ten feet shorter than the old one. There are more antennas on this tower, but all of the new antennas together present less wind load and weight than the old antennas. Except for the very bottom section, the new tower is constructed out of entirely new hardware, and has been regularly inspected for wear.

The verticals and wire antennas at N5XU

A six meter vertical on an eight foot mast mounted to one of the largest vents on the roof. Wire dipoles for 40 meters and 80 meters are strung between the tower and the east penthouse. You might find it easier to see the feedline that seems to rise up into thin air from the roof! A longwire antenna goes from the penthouse to another building about 300 feet away out of frame to the right. Check out the club station history for the funny story of how that antenna was put in place.

The 50 MHz vertical is one of the more recent additions to the station. It occasionally will hear stations better than the Cushcraft 50S3 during sporadic E openings. It is also useful for working the occasional mobile station with vertical polarization. If you look closely, you can see the tie down for the 30 meter inverted-V wire antenna at the vent where the mast is mounted. Another recent addition is a Hustler G6270R vertical for 144 MHz and 440 MHz. It is on extended loan from a club member. in the photo to the left, the six meter vertical is closest, and the dual-band vertical is further away; the 80 meter dipole is on the left, and the 40 meter dipole is on the right. In the bottom left corner of the frame, you can see the longwire that extends over to ENS.

The satellite antennas at N5XU

The club has a mast with antennas designed for satellite communications. A fifteen foot galvanized steel mast is bolted to the stairway railing just outside of the club station. Atop the mast is a Yaesu G-5500 azimuth/elevation rotor. This rotor has an eight-foot long, solid fiberglass boom, painted black, on which three antennas are mounted: a ten-element cross-polarized yagi for 145 MHz, an eight-element, cross-polarized yagi for 435 MHz, and a barbecue grill dish and downconverter for 2.4 GHz.

The club has plans to add more antennas as we acquire radio equipment for more UHF bands. Because we have literally run out space on our current tower, this means that we must consider building a second (east) tower. Our present hope is to install a bracketed tower beside the other penthouse on the roof of the building. We would be able to rearrange the antennas to have space for new microwave bands on the current tower, and more HF antennas on the new tower. This would allow us to add a small 40 meter yagi to our station. We might also be able to add a larger 50 MHz yagi on a separate rotor from our other VHF antennas; this would be a tremendous help during VHF contests, as we could point the six meter antenna in the direction where Eskip propagation is happening, and point the other antennas at whatever local station we need to work.