From the time I became licensed, just a little over 5 years ago, I have been using a trusty Diamond X50A antenna mounted on one 5-foot galvanized steel mast on an eave mount, putting the antenna about 4 feet above the roofline. The apex of the roof is approximately 30 feet from the ground. This antenna has served me very well, and with it I could reliably hit most of the repeaters in the area, as well as work stations on simplex up to about 15 miles away. Last year, I added a Cushcraft AR-6 Ringo for 6 meters. When there is a 6M opening, this antenna works OK and I worked quite a few distant stations (see previous posts under the category 6 Meters). However, because of the vertical polarization, I had difficulty working some stations in nearby grids who have horizontally polarized antennas. Also, the Ringo would frequently detune for mysterious reasons. Even though it was mounted on a telescoping mast, it became tiresome to frequently lower and retune it.
When my friend Rusty inquired about renting a 50-foot articulating boom lift to do some antenna work at his house, I thought now might be a good time to upgrade both antennas. I got a Diamond X300A for 2M/70cm, and a M2 HO Loop for 6M. I also got some new 5-foot galvanized masts and 55-feet of new RG-213 coax. My ham friends came over this morning to remove the existing antennas and install the two new antennas. Special thanks to KG4HIR Rusty, KG4HIQ Earl, W4EFS Walter, and KK4ZHT Eric for working all day on this project in the heat and humidity! Eric and Walter did all of the work in the bucket, and Rusty and Earl did the majority of assembly and adjustment of the antennas on the ground.
For this installation, we used three sections of 5-foot galvanized mast (for a total of 15 feet). Approximately 2 feet of the first section sits below the roof apex in the bottom of the eave mount, so about 13 feet of mast is above the rooftop. The X300A, which is a 10-foot antenna, is mounted on top, and the 6M horizontal loop is mounted about 5 feet below that. We used the existing LMR400 coax for 2M/70cm, and the new RG-213 coax for 6M. We tested the SWR and impedance on both antennas on temporary masts at about 15 feet above ground, and both antennas had great readings as assembled – no need for adjustments. I thought we might have to adjust the 6M antenna once it was in place above the roof, but the SWR stayed about the same at 1.2:1.
With the lift bucket extended, Eric took some photos that give an “antenna-eye” view from the rooftop.
Since we already had the lift, I took advantage of the opportunity to place a couple of ropes and pulleys for future use. The first about 40-45 feet up in a hickory tree, and the other on an old utility pole beside the driveway.
We had to take a short break for rain and thunderstorms. (The new antennas survived their first thunderstorm.) Even though there were a few adjustments made along the way, overall the project went as planned and was successful. Unfortunately, we did not have the same luck earlier in the day at Rusty’s house, because we could not get the lift into a position where the bucket would reach his antenna mast. I sure wish that had gone better.
I have not yet had a chance to fully test the performance of the new antennas. The new 2M/70cm has higher gain and is mounted 10 feet higher than the previous antenna. The 6M HO Loop is very narrow-band, but the SWR is nearly perfect at 50.3 MHz, so it will be great for digital and CW work. I did tune to 50.313 MHz and could hear and decode lots of FT8 from stations participating in the ARRL June VHF Contest. I’ll make some additional posts with my observations about the performance as I operate more with these antennas.
