Amateur Radio Station Design And Construction

March 19, 2013 by fkemmerer

Station Design And Construction

A little ways back, John (W1MBG) discovered our Blog and approached us about doing a presentation for the Nashua Area Radio Club (NARC) on the design, construction, and operation of our recently completed station. The NARC group invited us to their March meeting where we shared our presentation with the nice group of folks in the Club. I wanted to post an overview of what we shared as well as a link to the full presentation so that our readers can have a look at the material and hopefully benefit from the information that we have assembled. I have also used this post as an opportunity to create an index to all of the articles on this Blog related to the design, construction, and performance of our station.

Topics Covered

Our new station project involved both the construction of a dedicated room for a new shack and a tower-based antenna system. It took us about 1 1/2 years to build our station including the associated antenna system and we covered quite a number of areas during the project. Our presentation focused on some things that we did to plan and build our station that should be useful to many Hams building or upgrading anything from a simple station to an all-out effort to create a state of the art multi-op station.

Station Goals

I think that it’s important to begin a new or upgrade station project by thinking through and writing down the goals that you have for your new station prior to purchasing equipment or beginning construction. This step is important because it helps you to think through what you want to accomplish and serves as a high-level blueprint for making the design, equipment selection and construction decisions as you build your station.

Radio Shack Layout

We put considerable time and thought into the design of the room and operating area for our new shack including many rounds of drawings and some “human engineering” to arrive at the final room layout. While not every Ham will build a dedicated room for their shack, some careful thought put into the layout of the operating and storage areas for your shack and the associated support systems is an important design step.

Antenna System Planning

The other major element in the design of our station was a new tower-based antenna system. We had some pretty expansive goals for the band capabilities and associated performance of our new antenna system and the presentation explains how we went about developing and executing a plan to meet our goals.

Additional Antenna Construction

Since the initial installation of our tower antenna system, we added an 8-Circle Vertical Receive Array for the Low Bands and we’ve reinstalled our SteppIR BigIR Vertical Antenna. These new antenna systems provide important additional performance on the low bands and during contests. We’ve also added an Antenna System and Electronics for LEO Satellites.

Station Automation

We’ve also installed an SO2R and Station Automation System from microHAM. The microHAM system enables much smoother and less error-prone operation of our station and enables SO2R and Multi-two operation during contests.

Virtual Station Tour

Our presentation includes several slides that cover the construction of our new shack and tower as well as the feedline, antenna, power, and other supporting systems. The end result of all of this work is shown via a few slides that provide a “Virtual Tour” of our station.

Virtual Station Tour – Operational Videos

The “Virtual Station Tour” slides contain several videos. You can play these videos below.

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Other posts in this Blog contain more detailed information and many additional pictures and videos about our station. See the index of links at the end of this post to view more detail about the areas that interest you.

Station Performance

Our new station has been complete for several months now and we wanted to take some time to look at how it is performing against our original design goals. As you can see from the above slide, we are on a good track to meet or exceed all of the original goals that we set during the planning stage of our project.

What We Learned

Finally, we shared some additional information about what we learned during the project and a set of links to various sources of equipment and information that we used to complete our new station (see the full presentation). This Blog contains many more details (and pictures) about the design and construction of our station for those who are interested. Some good places to begin are categorized in the index of links below:

A Tour Of Our Shack

Shack Design and Construction:

Antenna and Tower Design:

Tower Construction:

Antenna Construction:

Tower Integration:

Station Integration:

Station Operation and Performance:

I hope that you can apply some of the ideas and information shared here to building or improving your station. We’d also like to extend a special thanks to John, W1MBG and the NARS Group for encouraging us to create and share this presentation. We are available to provide this presentation to other clubs or Ham gatherings. If your club or event is interested, please contact us at ab1oc@arrl.org.

Fred, AB1OC

First Winter With A Tower

March 11, 2013 by fkemmerer

Tower in the Snow

It seems that our tower is holding up well in its first winter here in New Hampshire, USA. We have not had a great deal of wind or any major ice storms this year but we have had quite a bit of snow. The antennas and the other equipment on the tower seem to be holding up very well including the two large SteppIR DB36 Yagis. The picture above shows a nice contrast of the tower and its antenna against a recent snow storm in progress here in New England.

– Fred (AB1OC)

Site of the Day – K9CT Contest Station

November 29, 2012 by fkemmerer

One of our readers Craig, K9CT has built a very nice Contest Station. The above video is an overview of his station’s antenna farm – well worth watching! Craig also makes use of Stacked SteppIR antennas in his setup and his station features an 80m yagi as well as a 160m vertical array. I think many of our readers might enjoy taking a look at the K9CT contest station website. Check it out via K9CT Contest Station.

– Fred, AB1OC

Tower CAM

November 5, 2012 by fkemmerer

Tower CAM In The Shack

After our recent experience with Hurricane Sandy, we learned that its important to monitor the impact that high winds are having on our antennas so that they can be pointed to minimize wind loads. We cannot directly see our antennas from inside our shack where our rotator controllers are located so this involved many trips up and down the stairs between our shack and the outside where we can see how the antennas are doing in the wind. To solve this problem, we decided to take advantage of the Video Monitor that is installed in our shack and install a camera that lets us view our antennas on the tower from inside the shack.

There are many closed circuit security cameras on the market that are designed for close range surveillance of entry points but it is more difficult to find a camera that does a good job at the 100 ft+ distance between our house and the antennas on our tower. After some research, we settled on a Long Range Outdoor Security Camera from LOREX. This camera has a lens that is well suited for longer range viewing and also features higher resolution and frame rates than most security cameras. The first step in the installation was to install the camera in a sheltered area on our house facing the tower.

Tower CAM

Mounting the camera so that it would look up at the antennas was a bit of a challenge (most security camera mounts are designed to look down, not up) but we were able to work this out after some experimentation. It was then an easy matter to run the single cable which caries both the video signal and power from the camera to the Video Monitor in our shack. As you can see from the video which follows, the setup worked out pretty well and we can now see what our antennas are doing from inside our shack. It’s also nice to be able to monitor the rotation of the antennas when we are operating.

– Fred (AB1OC)

Hurricane Sandy

November 2, 2012 by fkemmerer

Hurricane Sandy (Courtesy NOAA)

As many probably know, the northeast was hit by Hurricane Sandy, a huge storm this past week. Our thoughts and prayers go out to all of the people who were effected or hurt by this tragic weather event. The pictures of the devastation in New York City and New Jersey, USA are unbelievable and saddening.

Several of our friends have asked how we and our station fared during this major weather event. We sustained only minor impacts due to some 50+ mph wind gusts – many branches down and the top SteppIR DB36 Yagi on our tower turned on the mast. We also experienced an early life failure in our K0XG Ring on Saturday prior to the storm. A power rectifier failed and left us unable to turn the ring. Fortunately, the ring failure left the lower of our two SteppIR DB36 Yagis pointed in a safe direction relative to the highest winds during Hurricane Sandy. We were without power for several hours on Monday evening but our generator covered for that nicely. The turned antenna and the failed rectifier were easily corrected after the storm passed and we are back to normal here. All in all, the new Antenna System came through the storm quite well. Thanks to everyone for their concerns for us.

– Fred (AB1OC) and Anita (AB1QB)

First Tower Part 21 – Antennas On The Tower (Final Odds and Ends)

November 2, 2012 by fkemmerer

Up the Tower

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.

Finished Tower Base

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.

160m Inverted-L With UNUN

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.

160m Inverted-L SWR

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.

Stage 1 – Antenna Switching Consoles

The second stage consists of a switch at each radio which selects among the assigned antennas.

Stage 2 – Antenna Switching At Radios

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.

Bandpass Filters

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.

Diamond X300NA Antenna On 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.

Wire Antenna Anchor

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.

Up The Tower At Sunset

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.

Completed Tower And Antennas

You can read more about our tower project via the articles which follow:

– Fred, AB1OC

First Tower Part 20 – Antennas On The Tower (System Complete)

October 19, 2012 by fkemmerer

Final Tower

Well, after several more days of intense work, our new tower and antenna system is complete! The work this week began with the installation of our Second SteppIR DB36 Yagi on the tower. Matt and Andrew from XX Towers made short work of this step. We began by rigging the second DB36 at the base of the tower and we removed one set of guy lines and replaced them with temporary guys so that we could pull the large yagi straight up the tower.

SteppIR DB36 Number 2 Ready for Tower

We removed the 6m passive element that is closest to the center of the antenna (and therefore the tower) before pulling the antenna up the tower to avoid damaging it. Once the antenna was up to the 60 ft level, Andrew positioned it on the K0XG Ring and clamped it in place. The following picture shows the DB36 installed on the rotating ring. Next, Andrew installed the phasing line from the lower beam to the Custom Feedline Breakout System at 80 ft and he also ran the control cable for the second DB36 to the base of our tower. This completed our 4 over 4 array system.

Looking Up The Tower

I did a quick test using the SteppIR Controller and confirmed that the second DB36 was working correctly. Its SWR performance is slightly different than the upper antenna on the lower bands. This is, no doubt, due to the large, lower antenna’s proximity to the ground. We also found that we had a defective position sensing pot in the K0XG Ring. Fortunately, Matt had a spare and returned the following day to replace it. With this fix, the ring worked fine. Here’s a video of the second antenna turning around the tower on the ring.

To create clearance for the lower antenna, we modified the 80m-Loop that was installed previously into a diamond. This moved the resonance frequency of the loop somewhat higher so we removed a few feet of wire to bring it back to the center of the 75m DX Window.

We also built a 160m Inverted-L antenna. Since my SteppIR BigIR Vertical antenna was previously located only a few feet from the tower, I have a radial field and base plate that could be reused for the 160m antenna. The radial field consists of 48 buried radials each 85 ft long. The existing radial field was built using a DX Engineering Radial Plate. We rigged a wire up from the connector on the plate to one of the Phillystran guy lines on the tower and then ran the wire up along the guy line to form the top of the inverted L. After some checks with an antenna analyzer, we determined that the antenna needed a little bit of base inductance to resonant at the right spot in the 160m band. Matt had a suitable core available so we build a simple inductor and connected the antenna to the connector installed on the DX Engineering radial plate. The antenna was completed with a short length of LMR400 UltraFlex coax to the DX Engineering Remote Antenna Switch on the tower.

160m Inverted-L

With this step done, our new antenna system is complete! We managed to cover all amateur bands from 160m through 70cm (except for 1.25m) on a single tower. I have some cabling and finishing touches to complete to put everything into operation. One step that is done is to complete the shack entry cabling and waterproofing. Here’s a picture of the results of that step.

Final Shack Entry

I did a little testing on the SteppIR array on 20m and on the modified 80m loop. The array is very strong on 20m – it produced some really good signal reports including on report of 59 + 60 dB into LA, USA (about 1,400 miles from me). I have also gotten many signal reports from Europe in the 59 + 10 dB to 59 + 30 dB range. All good signs. I am also seeing some effective gain (about 5 – 10 dB) on 40m. This is probably more due to the lowering of the takeoff angles and tightening of the vertical pattern due to the array than stacking gain. Also, the ability to use the array with the two antennas out of phase is great for close-in work and for filling in holes in the pattern.

The 80m loop is better in the diamond configuration than as a Delta Loop. It now has a little wider bandwidth and is more omnidirectional, covering Europe more effectively. I don’t think a second loop facing Europe will be needed at this point.

Tomorrow will be a day to get the 2M and 70cm on the air, waterproof the tower side of the feedline conduits and tie up loose ends. I will try to post some additional operating information as well.

You can read more about our tower project via the articles which follow:

– Fred, AB1OC

First Tower Part 19 – Antennas On The Tower (System Integration)

September 28, 2012 by fkemmerer

Electronics and Equipment On The Tower

Well, it has been a very busy couple of weeks related to the construction of our new station, and we have made great progress. Matt and Andrew from XX Towers were at our QTH again last week, and we completed the integration and testing of all the gear on our new Tower. This included adding the planned 80m Delta Loop antenna. This post will explain the final integration process for our new antenna system, including the setup and testing in our shack.

My work for this step began with the construction of 8 custom coax cables to complete all of the connections between the antennas, electronics, and hard-line feeders on the tower. These were built from a mix of LMR-400 UltraFlex and LMR-600 UltraFlex coax and a combination of N and UHF crimp-on connectors. I also prepared 8 control cables for all the electronics and equipment on the tower.

Control Cables

The first order of business was to connect all of the coax cables to complete the feed lines. This work included connecting the M2 Systems 2m and 70cm Yagis to their Tower Mounted Pre-amp Systems and then connecting the pre-amps to the hard-line feeders for these antennas. We installed the phasing line from the upper SteppIR DB36 to the Custom Feed-line Breakout Box at 80 ft. This device was then connected to the DX Engineering PS2B Broadband Phasing System, which will be used to create a 4 over 4 array. The final step in the coax work was to connect both the PS2B and the Feed-line Breakout Box to the two 7/8 hard-line cables on the tower.

The two control cables for the M2 Rotator and the K0XG Rotating Ring were already on the tower, so Matt and I set up the two Green Heron Rotator Controllers at the base of the tower and connected them to their associated control cables. We first tested the M2 Rotator at the top of the tower, and it worked on the first try. We set the rotator in the middle of its range and set the controller to make this direction North. We drove a stake at the edge of our yard to point True North, and Andrew adjusted the mast to point the top three Antennas North and locked down the mast to rotator clamp.

Next, we tested the K0XG Ring with the second Green Heron controller. I decided to get a pair of Green Heron controllers in their black version, and this required the folks at Green Heron to modify their deluxe version of their controller for the K0XG Ring. On the initial test, the ring did not turn. We could tell that the relays in the ring control box at the base of the tower were being energized, but the ring did not turn. After troubleshooting with a voltmeter, we determined that the modified Green Heron controller was not supplying power to the Ring’s motor control relay. We called the folks at Green Heron, and after some checking of the jumpers inside the modified Green Heron controller, we determined that the addition of a jumper would solve the problem. We did this, and the ring worked fine!

Next, we sent the rest of the control cables up the tower to Andrew for connection to the devices on the tower. These included:

The control cable for the SteppIR DB36
A pair of control cables for the M2 Antennas 2m and 70cm Pre-amp Systems
The control cable for the DX Engineering Broadband Phasing System
The control cable for our Custom Feed-line Breakout Box

Andrew set about connecting all of these control cables while Matt built an 80m Delta Loop antenna. The apex of the delta loop is 95 ft, and the base is about 16 ft off the ground. We aimed it at the NNE, and fed in the middle of the bottom section.

80m Delta Loop on Tower

The 80m Delta Loop antenna is connected to a DX Engineering 8 Port Remote Antenna Switch at the base of the tower, which is connected to the shack via a 1/2″ hard-line feeder. I am planning to add a 160m Inverted-L antenna and possibly a second Delta Loop facing ESE in the future – the DXE Remote Switch will allow us to select among these antennas from the shack. We tuned the Delta loop for resonance at 3.80 MHz for phone work. I built a control cable for the antenna switch and set the controller up at the base of the tower so we could test the Delta Loop. After completing the Delta Loop, we measured the antenna’s SWR performance and found that it has an SWR of 1.0 at 3.80 MHz 2:1 SWR bandwidth of 180 kHz – perfect!

Next, we added the connectors to the shack end of all the hard lines and setup an SWR meter at our shack entry for end-to-end testing of the antennas and feed lines.

Feedlines at Shack

I also connected the controller for the DXE PS2B Broadband Phasing System. We connected a 50-ohm dummy load in place of the lower SteppIR antenna to test the array phasing system and feedline breakout box. I used a 28V power supply to close the T/R relays in the 2M and 70cm pre-amps which connected their feed lines directly to the antennas, bypassing the pre-amps for testing. Finally, I connected the SteppIR DB36 controller and calibrated the DB36’s elements. After placing the SteppIR on 20m and setting the PS2B to connect to the upper DB36 only, we measured the SWR at the end of the 7/8″ hard-line at the shack entry – success, a good SWR curve!

We did have some initial problems related to a combination of reversing the feed-line connections for the upper and lower DB36s at the PS2B and a wiring error in the PS2B controller. Quick troubleshooting identified both of these problems, which were easily corrected. With this done, we verified the connection to the dummy load (future lower DB36) and tested the Feed-line Breakout System – both of which worked correctly!

The final step in the test of the tower-mounted equipment was to put the two M2 Pre-amp Systems in transmit mode and test the SWR performance of the 2M and 70cm beams at the entry to the shack. I was a bit anxious about this step as both antennas’ resonance was a little low when they were previously tested close to the ground. A quick SWR test on both antennas verified that they performed exactly to M2’s specifications with SWR over the specified bandwidth of less than 1.2:1.

Next, I connected all of the control cables to ArraySolutions Surge Suppressors at the base of the tower and made up the final control cables to the shack. This step was a big job as our tower has about 100 control leads to handle all equipment and electronics.

Control Cables at Tower Base

With this step complete, we routed the control cables through the conduits we had placed in our yard to the shack and then to the shack through the existing building cable entries.

Control Cables and Feedlines in Conduits at the Tower

The final step in the integration of the new Antenna system was to set up all of the various controllers in the shack and connect them to the control cables from the tower and to our radios where appropriate. We first focused on the rotators and the HF-related antenna controllers first. I arranged all of this gear in the shack and connected the control cables one by one, testing the equipment on the tower as I went. The arrangement of the controllers mirrors the location of the associated equipment on the Tower, making it easier for Anita and me to use the equipment.

Rotator and HF Antenna Controllers in the Shack

The following table shows what the various controllers do. The SteppIR controllers on the right are interfaced with our radios so that their associated antennas automatically track the frequency of our radios as they are tuned and adjust the associated antennas to remain resonant. The controllers for the DB36 Yagis have some interesting features. They can reverse the direction of the antenna in a few seconds with a touch of a button (saving time and wear on our rotators). They also have a bi-directional mode which configures the DB36s to listen both front and back at the same time. This is a useful feature for contesting and operating on nets. The Green Heron Rotator Controllers on the left will be interfaced with our shack computers to allow our station control software to point our antennas based upon the click of a mouse. More on this in a future post.

Feedline Breakout Controller	DXE HF Broadband Stack Controller
Low Band Antenna Switch on Tower	Controller for Upper SteppIR DB36
Upper Rotator (Yagis on Mast)	Controller for Lower SteppIR DB36
Lower Rotator (K0XG Ring)	Controller for SteppIR BigIR Vertical

The other part of the controller integration step in the Shack was to connect the M2 S2 Sequencers to the M2 Tower-mounted preamp systems and to our Icom IC-9100 Transceiver. The sequencers are shown below atop our Palstar Dummy Load. These devices ensure that the proper sequence of shutting down the Tower mounted Pre-amps and switching the remote T/R relays is followed when our IC-9100 is key to transmit. These controllers also have provisions to sequence power amplifiers which we plan to add in the future.

M2 Sequencers and Palstar High-Power Dummy Load

After some testing and a little troubleshooting work, all of the HF-related antenna systems were up and running properly in the shack. I had the chance to operate the new HF antenna systems last evening, and the performance is amazing! In a 6-hour stretch, I was able to work 5 new countries and perhaps 10 or so new band countries with a combination of the SteppIR DB36 Yagi at 100 ft and the 80m Loop. This included generating a nice pileup into Europe last evening on 40m. I am consistently getting 59+10 dB or better signal reports into Europe on 40m and have gotten a few 59 + 10 dB reports into Japan on 15m – more than I expected!

The 80m loop is also a great antenna. I am getting signal reports ranging from 59+ to 59+40 dB into Europe, and my ability to “hear” DX stations on 80m is vastly improved!

My goals for this weekend include beginning to build the second of our two SteppIR DB36 Yagi’s and hooking up and testing the 2m and 70cm Yagis.

You can read more about our tower project via the articles which follow:

– Fred, AB1OC

First Tower Part 18 – Antennas On The Tower (Preparation and Upper Yagis)

September 26, 2012 by fkemmerer

Antenna Stack And Tower At Night

As I sit here writing this blog post at the end of the second day of work to install antennas on our new tower, I can reflect back on some pretty memorable experiences. I have certainly learned a great deal during the last few days.

The work began this past weekend with the final assembly and test of our 2m and 70cm beams. Both beams use mast-mounted boom truss plates and I wanted to fully assemble these ahead of the installation on the tower to set the boom support lines to the proper length and give them a chance to stretch a bit. To do this, we made a set of 10 ft test masts from some PVC electrical conduit. Shown here is our M2 2M18XXX 2m beam installed on the 3″ test mast. We also installed a short length of coax on the 2m beam so that we could check the antenna’s SWR performance prior to installation on the tower.

2M Yagi Test

Our M2 440-21ATV 70cm beam has a 14 1/2 ft boom and did not come with a boom support truss. I am using LMR-600 UltraFlex coax for the rotator loop and feedline connection to this antenna. LMR-600 UltraFlex coax has a good deal weight to it. To prevent the boom from sagging due to the weight of the coax, M2 Systems provided us with a custom boom truss setup which is shown installed on the test mast. This should improve the reliability of this antenna and be easy to install. I also installed jam nuts on the boom truss turnbuckles for the 70cm and 2m antennas to prevent them from coming loose once they are on the tower.

70cm Yagi Boom Truss

With this work done, we were ready for Matt and Andrew at XX Towers. They arrived on Monday morning and began by prepping the 70cm and 2m beams for installation on the tower. I made up feedline extensions to go from the M2 Pre-amp Systems for these antennas on the tower to the antennas. I made up the extensions using LMR-600 UltraFlex cable for the 70cm beam and LMR-400 UltraFlex cable for the 2m beam, both with crimp-on N-connectors. We are using a 2″ insulated mast extension (from M2 Systems) so that the 70cm beam does not “see” the mast which would adversely affect the antenna’s pattern. The 70cm beam is shown below installed on the fiberglass mast extension which is about 5 ft long. Matt attached the 70cm antenna, boom truss, and feedline to the mast extension on the ground to minimize the work required on the tower. He also attached the feedline to the 2m beam on the ground.

70cm Beam Prep

Finally, noting the rubber element boots on the SteppIR antennas are prone to UV damage, Andrew covered all of the boots on our SteppIR DB36’s with a layer of electrical tape to give them some additional UV protection and extend their life.

SteppIR DB36 Final Prep

With all of the prep work done, it was time to start the installation of antennas on the tower. The first step was to pull the 3″ steel mast up the tower and clamp it inside the mast thrust bearing in preparation for the 70cm beam installation.

Mast Going Up The Tower

Next, the 70 cm beam and mast extension went up the tower and were installed on the mast. The total length of the mast above the tower plus the extension will be about 20 ft. This will leave about 5-6 ft of the 3″ steel mast inside the tower which is just about right. After consulting with Jason at M2 Systems, we settled on the spacing between the three antennas on the mast – 6 ft between the 70cm and 2m beams and 10 ft between the 2m beam and the SteppIR DB36 which will be just above the top of the tower. This put the installed heights of the antennas at 118 ft (70cm yagi), 112 ft (2m yagi) and 101 ft for the SteppIR DB36 yagi.

70cm Beam Going Up The Tower

After the 70cm beam was installed, Andrew pushed the mast up a few feet to prepare for the installation of the 2m beam and we hauled the 2m beam up the tower reflector end first.

2M Beam Going Up The Tower

Shown here are the 2m and 70cm beams fully installed on the mast. The 2m antenna has a 36 ft boom but it looks quite small at 100+ ft!

2m And 70cm Beams On The Tower

We choose an M2 OR2800PXAZ prop pitch style rotator to turn the upper three antennas on our tower. This heavy-duty unit was a good choice given the size and weight of the SteppIR DB36 yagi that it will be turning. Next up the tower was the rotator and associated base plate. With this installed, the mast was pushed fully up in preparation for the installation of the SteppIR DB36.

M2 Rotator

The DB36 is a big antenna and it weights about 165 lbs fully assembled. The best way to get it onto the mast at our site was via a tram line system. With the tram line cable rigged to the mast and a tree in the woods next to our yard, we attached the DB36 to it via a pulley and some cable clamps to anchor the pulley on the tram line. Matt then used a pair of come-a-longs to take the slack out of the tram line which lifted the DB36 off the ground. We then looped a light guideline around the end of one of the elements so that we could steer the DB36 as it went up the tower.

SteppIR DB36 Suspended On Tram Line

The next picture shows the DB36 about halfway up the tower. Note that we removed two of the three sets of top guys from the tower prior to this step to avoid the DB36’s elements entangling in the upper guy wires.

SteppIR DB36 Up The Tower On Tram Line

Once we had the DB36 fully up the tram line, Andrew attached it to the mast. All in all, the tram line system worked very well. It was an awesome experience to use this approach to lift such a large antenna into place!

SteppIR DB36 Installation On Mast

With the three beams on the tower, the next order of business was to install the hard-line coax feedlines on the tower. We are installing a total of five hard-lines on our tower:

A run of 1 5/8″ hard-line for the 70cm beam
A run of 1 1/4″ hard-line for the 2m beam
Two runs of 7/8′ hard-line for the two SteppIR DB36 beams
A run of 1/2″ hard-line for the planned 80m and 160m wire antennas

The reels of hard-line coax are shown below.

Hard-lines

Unfortunately, a business trip prevented me from being at home to help Matt and Andrew on the second day of the installation. They made a great deal of progress as you can see from the pictures below. They installed the K0XG ring rotator at the 60 ft level. The ring will turn the second of the two SteppIR DB36’s that will go on the tower. They also installed all of the tower-mounted electronics and switches. These are shown in the picture below – the items from top to bottom include: the M2 2m and 70 cm tower-mounted pre-amp systems, a DX Engineering Broadband Antenna Phasing System and our Custom Feedline Break-out System (both installed at 80 ft, the smaller light-colored box on the left is the feedline break-out), the K0XG ring rotator, and finally our previously installed Davis Wireless Weather Station at the bottom right. The K0XG Ring is a 115 VAC powered heavy-duty until that is extremely well-built. It should do a great job of rotating our lower SteppIR DB36 around the tower. You can also see four of the five hard-line cables in the picture.

K0XG Ring Rotator At 60 ft

The devices installed at the base of the tower include the control box for the K0XG Ring (left) and a DX Engineering Remote 8 Port Antenna Switch for the wire antennas (right).

Electronics At Tower Base

I now need to build several sets of LMR-400 UltraFlex cables to connect the hard-lines and antennas to all of the electronics. Each of these cables will be tested with a dummy load and an antenna analyzer to ensure that they perform correctly before they go on the tower. The cables that run between the Stack Match, Feedline Break-out and the two SteppIR DB36’s must be built identically to ensure the best performance from the array of the two SteppIR’s. All of this is going to take a couple of evenings to complete. Matt and Andrew will be back later in the week to complete the installation of the feedlines and control cables.

You can read more about our tower project via the articles which follow:

– Fred, AB1OC

Climbing The Tower (Again)

August 19, 2012 by fkemmerer

AB1OC in Climbing Gear

After using our new Weather Station for a few days, we decided to move it higher on the tower to get it somewhat out of the shelter of the surrounding trees in our backyard for more accurate wind speed readings. My second attempt at climbing the tower greatly benefitted from what we learned the first time. Namely, prepare as much on the ground as possible to simplify the work on the tower and put the climbing gear on just before climbing the tower. The plan was to move the weather station from the 33 ft level it was at to just below the first set of guys at the 50 ft level.

Our House from the Tower

The first step was to climb to the 50 ft level to rig a rope and pulley to haul the weather station up to the 48 ft level. After rigging the rope and pulley, I took a few pictures of our yard and our other antennas from this vantage point. Anita (AB1QB) helped me by acting as my ground crew.

Ground Crew (AB1QB)

The next step was to climb down to where the Weather Station was at the 33 ft level and attach it to the haul rope via a sling. Once this was done, I unbolted it from the tower and climbed back up to the 50 ft level and reattached it to the tower at 48 ft.

AB1OC on Tower at 50 ft

The Weather Station is now installed at the 48 ft level and is providing much more accurate wind readings.

Weather Station at 48 ft

As my tower climbing skills and confidence increases, I will attempt to climb to the top of the tower to take some additional pictures.

– Fred (AB1OC)

Our HAM Station

Notes on the construction and operation of a multi-op Amateur Radio Station

Category Archives: Tower Construction and Maintenance

Amateur Radio Station Design And Construction

First Winter With A Tower

Site of the Day – K9CT Contest Station

Tower CAM

Hurricane Sandy

First Tower Part 21 – Antennas On The Tower (Final Odds and Ends)

First Tower Part 20 – Antennas On The Tower (System Complete)

First Tower Part 19 – Antennas On The Tower (System Integration)

First Tower Part 18 – Antennas On The Tower (Preparation and Upper Yagis)

Climbing The Tower (Again)

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