We completed all of the integration steps for our new antenna system recently and finally got everything on the air. I guess it’s safe to say a big project like this is never truly “all done” but we have all of the important work completed.
I spent some time weatherproofing all of the cables as they enter and exit the conduits to the shack. The conduits are constructed to allow water and condensation to drain into the ground so the goal here was to keep the water entering the conduits to a minimum. I also spent some time to make the cabling at the base of the tower a little neater and to ensure that things were securely fastened. I also weatherproofed several connectors at the tower and shack end of the feedlines and antennas.
We also installed a 1:2 UNUN on our 160m Inverted-L antenna. The antenna has an impedance of approximately 25 ohms at resonance which makes the SWR a little high and limits the antenna’s 2:1 SWR bandwidth.
We secured a 1:2 UNUN from Balun Designs to better match our 160m antenna to the 50-ohm feedline. As you can see from the picture below, the UNUN worked out quite well and the resulting 2:1 SWR bandwidth of our 160m Inverted-L is about 60 kHz at the base of the antenna.
Our final antenna farm consists of the following antennas:
- Two SteppIR DB36 Yagis in a 4 over 4 array covering 80m – 6m
- An 80m loop
- A 160m Inverted-L
- A Buckmaster Off Center Fed (OCF) Dipole covering most bands from 80m – 6m
- A Par 6m Wire Moxon Beam
- An M2 Systems 2M18XX Yagi with a tower-mounted preamp for weak signal 2m work
- An M2 Systems 440-21ATV Yagi with a tower-mounted preamp for weak signal 70cm work
- A Diamond X300NA Vertical Antenna for 2m and 70cm repeater work
The next project was to re-cable our antenna switching consoles to fully accommodate the new antennas including the 2m and 70cm Yagis as well the two feedlines to the 4 over 4 array of SteppIR DB36 Yagis. Our current antenna switching system consists of a manual array of switches that can route up to 8 antennas to any of four radios. This is done via two stages of switching. The first selects which antennas are assigned to which radios.
The second stage consists of a switch at each radio which selects among the assigned antennas.
This system, in conjunction with a set of ArraySolutions FilterMax III Switchable Bandpass Filters, allows both Anita and I to operate simultaneously of different bands or to operate in SO2R or Multi-Multi modes. We can use our Custom Feedline Breakout System to route our two SteppIR DB36 Yagis to different feedlines so that we can each use of the two HF Yagis simultaneously.
Our tower gets quite a workout when Anita and I are both operating simultaneously!
The switching for 2m and 70cm is much simpler. Our shack has one radio (an Icom IC-9100) setup for these bands, and we use two UHF Antenna Switches in our console to select between our M2 Systems Yagis on these bands or a Diamond X300NA repeater antenna on a 45 ft mast.
With the re-cabling of the antenna switching complete, we got our new 2m and 70cm Yagis on the air and fully tested the associated preamp and sequencer systems. This setup works very well with our Icom IC-9100 radio. The preamps provide about 20 dB of gain, and the M2 Systems S2 Sequencers automatically switch them in and out when we key up the IC-9100. The added gain from the preamps helps with weak signal work on the 2m and 70cm bands. You can see the sequencers in operations in the following video of a 2m SSB QSO with N1RJX.
It is going to be fun doing weak signal work on 2m and 70cm, and we are planning to participate in some VHF contests in the future. I also want to try some EME work when the moon is on the horizon. Our antenna switching setup on these bands can accommodate more antennas, and I am planning to add antennas for Low-Earth satellites and possibly EME work in the future.
I also integrated our Green Heron Rotator Controllers with our computers and the Ham Radio Deluxe Software we use. This allows us to point our beams with a mouse click. You can see the point-and-shoot rotator operation in action in the following video, which captures a QSO between PY7DJ in Brazil and 5H3CMG in Tanzania on 20m. Note how the signals come out of the noise as the 4-over-4 array of SteppIR DB36 Yagi antennas swing in the direction of the participating stations. You are hearing PY7DJ off the side of the array, but he is still quite strong. 5H3CMG indicated in an earlier QSO that he was using a low dipole and 100W. The strength of his signal is an indication of the performance of our antenna system.
We also cleaned up the supports for our 80m loop. It is important to have a setup that keeps constant tension on the support ropes when the anchoring trees move in the wind. We used the same setup that has worked well on our OCF Dipole for some time. This setup consists of a pulley attached to a tree and a rubber tarp anchor, which maintains constant tension on the support line as the anchoring tree sways in the wind.
Given that I had the ladders out to do this, I also took the opportunity to adjust the supports for our other antennas and do our annual antenna checkout and maintenance routine prior to the onset of winter.
At this point, we are looking forward to enjoying operating our new station! The work to date has been really rewarding, and we have learned a tremendous amount from everyone who has helped us. I guess some would say that all of this equipment would not be something they would want to have in their back yard but to a dedicated Amateur Radio operator, a tower and a stack of Yagis is truly a thing of beauty! I sometimes look up at the tower and stare at all the gear up there. Each item has a story and many good memories about the journey to get to this point.
So what comes next for our station? We plan to add a computer-controlled automated operating setup from microHAM, and we will most likely install it sometime this winter. We are also planning to set up our SteppIR BigIR Vertical in a new location and add a receive antenna system for the low bands. We are also considering antennas for Satellite operations, EME, … My next project is going to be to learn Morse Code and become active on CW.
You can read more about our tower project via the articles which follow:
- First Tower Part 1 – Ground Broken For New Tower!
- First Tower Part 2 – Tower/Antenna System Design Details And Equipment Ordering
- First Tower Part 3 – More Excavation For Feedline Conduits
- First Tower Part 4 – Tower/Antenna System Analysis And Design (Planning And EZNEC)
- First Tower Part 5 – Tower/Antenna System Analysis And Design (HFTA Analysis)
- First Tower Part 6 – We Have A Tower!
- First Tower Part 7 – 100 ft Tower Completed!
- First Tower Part 8 – VHF/UHF Antenna System Design
- First Tower Part 9 – Feedline Conduits And Electrical Power Complete
- First Tower Part 10 – Building Yagis (70 cm)
- First Tower Part 11 – Building Yagis (2m)
- First Tower Part 12 – Building Yagis (SteppIR DB36)
- First Tower Part 13 – Building Yagis (SteppIR DB36 Continued)
- First Tower Part 14 – Building Yagis (SteppIR DB36 Continued II)
- First Tower Part 15 – Building Yagis (SteppIR DB36 Completed)
- First Tower Part 16 – Building Yagis (Second SteppIR DB36 Completed)
- First Tower Part 17 – Feedline Breakout System
- First Tower Part 18 – Antennas On The Tower (Preparation and Upper Yagis)
- First Tower Part 19 – Antennas On The Tower (System Integration)
- First Tower Part 20 – Antennas On The Tower (System Complete)
- Complete Presentation on Amateur Radio Station Design And Construction
– Fred, AB1OC