The 2012 CQ Worldwide Phone Contest

November 2, 2012 by AB1OC

CQ Zones (Courtesy CQWW website)

Anita and I had the opportunity to use our new station as part of the 2012 CQ Worldwide Phone Contest this past weekend. We were both looking forward to working some new DX entities using our new antenna system and we were not disappointed! The contest also gave us the change to evaluate our new antennas in an environment where more DX stations are on phone than just about any other time of the year.

We each operated individually in the high power, single transmitter assisted category. We did not operate the full contest period due to a combination of travel on Fred’s part and the need to take time out to prepare our home and antennas for the approaching Hurricane Sandy. Our goals for the contest were mostly to work new DX entities and we did quite well in this area. Between the two of us we probably worked 200 new band-countries. Fred was also able to complete several SSB QSOs on 160m with our new Inverted-L antenna. Together, Anita and Fred completed about 400 QSOs during approximately 12 hours of combined operating time.

We are certainly much stronger into Asia with the new setup. Anita and I both worked modest stations in China, Japan, South Korea and several other countries in Asia during the contest. We are much more effective at making contacts into Africa than before and we were able to work several new countries in that region as well. We were also able to hold a frequency and run during the contest which was a new experience for us. We worked QSOs on all bands 80m – 10m (including a few on 160m).

Fred’s main goal was to get to 100 countries in the log on 80m and 40m to complete a 5 Band DXCC. He got close to this goal and finished with 96 Countries worked on 40m and 68 Countries worked on 80m. Anita wanted to make calls into Asia and complete her phone DXCC. She did quite well, finishing with 97 countries worked on phone and she worked a number of new countries in Asia including China, Indonesia, Guam, Mongolia and many JA stations.

All in all, we had a lot of fun working the contest and we are looking forward to upcoming RTTY and other contests. Where time permits, we will work a few for a “real score” to see how we do.

– Anita (AB1QB) and Fred (AB1OC)

Hurricane Sandy

November 2, 2012 by AB1OC

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 AB1OC

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 AB1OC

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 16 – Building Yagis (Second SteppIR DB36 Completed)

October 16, 2012 by AB1OC

Completed Second SteppIR DB36

We completed the assembly of our second SteppIR DB36 Antenna today. This is the last of the Yagi antennas for our new antenna system and tower. It will be installed on a K0XG Rotating Ring at 60 ft on our tower. The second DB36 will be able to be used as part of a 4 over 4 array, or it can be connected to a second feedline via the Custom Breakout System that we built to allow Anita and I to operate simultaneously. Our second SteppIR DB36 is identical to the first one at 101 ft except that it does not have the 80m dipole option installed. We elected not to install the 80m dipole on the lower DB36 as 60 ft is not really high enough for a dipole on 80m to be effective for DX work.

We covered the assembly of our first SteppIR DB36 in detail in a series of posts so we will only provide a summary of the assembly process for the second one. You can access the posts on the first DB36 via the following links:

There are some important differences between the second DB36 and the first one and I will cover those here. The first difference relates to the installation of this antenna on the K0XG Rotating Ring. The ring uses a boom clamp instead of a standard mast clamp system.

K0XG Ring Clamp

This required some U-bolts to attach the ring clamp to the boom of our second DB36 and to attach the boom truss pipe for the second DB36 to the clamp. Our local Hardware Store had clamps that we could use and after some modifications, including extending the threads on the clamps, glass beading, and a good coat Cold Galvanizing Paint, the K0XG Ring Clamp was secured to the boom of the second DB36. We were careful to locate the clamp in a position that would not interfere with the installation of the 6m passive which was to come later.

Ring Clamp-on Boom

The only other difference in the second DB36 was the absence of the 80m dipole option. This simplified the connector box wiring on the second antenna a bit.

Control Cable Junction Box

The second DB36 will be part of a 4 over 4 array so its important that the feedlines and related elements in the transmission path between our DX Engineering Broadband Phasing System and both antennas be identical. The upper DB36 has the 80m dipole option installed which inserts a 6 ft length of RG-213 coax and a switching relay into the feedline path of that antenna. To ensure the identical performance of the feedline system of the lower antenna, we installed the switching relay and the RG-213 coax on the lower antenna as well. Since we do not have the 80m dipole option installed on the lower antenna, the switch does not need to be connected to the control cable for the antenna. The addition of these components did affect the SWR readings on the ground and brought the SWR measurements closer to the first antenna indicating that the expense of the additional components to make the feedline systems a match was justified.

80m Dipole Switch and Coax

We tested the second DB36 on the ground to confirm that all of the elements were operating properly and that the SWR performance was consistent with the first antenna and repeatable. Everything checked out fine.

Antenna Test On The Ground

The last step was to tape up the rubber boots which hold the element housings in place. These boots are prone to UV damage and subsequent failure. The tape protects the boots from damage from the sun and extends their life.

Taped Element Boots

Our second SteppIR DB36 is now complete and will be installed on our tower tomorrow. As I mentioned in a previous post, the assembly of one of these antennas is a fairly big project. There are approximately 1,136 parts in a fully optioned SteppIR DB36 antenna! We took quite a bit of additional time to carefully assemble our two DB36’s and to protect them from the weather and sun as much as possible to extend their life. Some of the “added steps” included:

Wiping all metal parts with a solvent to remove any oil or dirt followed by a coat of WD-40
Treating all plastic and rubber parts with a coat of ArmorAll to improve their UV resistance
Coating all Fiberglass Parts and Poles with two coats of Clear UV Resistant Paint
Taping all of the Rubber Element Connecting Boots to Protect them from UV related deterioration
Extra time spent on carefully leveling the elements and the boom truss to ensure that the antenna was perfectly straight
A thorough set of resistance and operational checks of the antenna on the ground before installation on the tower
A second, final check of all hardware for proper tightness

I am sure that others have assembled one of these antennas in considerably less time than we did. I would estimate that each one required 50 – 60 total hours to complete (about 1 full-time week). The second one required less time than the first as a result of the experience gained with the first antenna as well as the lack of the 80m dipole.

The next step will be to put the second DB36 on the tower and test the stack. This will be the subject of a future post.

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

– Fred, AB1OC

How Many Parts In A SteppIR DB36?

October 11, 2012 by AB1OC

Completed DB36 Yagi

I am working on assembling the second of our two SteppIR DB36 Yagi’s and it is nearing completion. It’s hard to understand the amount of work that goes into building one of these antennas until you do one. Just for fun, I decided to work out a total count of parts and pieces that were installed or assembled as part of building our first SteppIR DB36. How many parts do you think there might be? The count I took is for a SteppIR DB36 with the following options:

80m Dipole
6m Passive Kit
Controller with Transceiver Interface and Tuning relay
Connector Junction Box
Element Truss Kits for all three Loop Elements

Take a minute and give your answer in the following pole. I will publish the count in my next post.

– Fred (AB1OC)

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

September 28, 2012 by AB1OC

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 AB1OC

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

First Tower Part 15 – Building Yagis (SteppIR DB36 Completed)

September 22, 2012 by AB1OC

Completed DB36 Yagi

We completed the assembly and testing of the first of our two SteppIR DB36 Yagi’s today. We installed the 80m dipole option on our antenna which provides a rotating dipole on 80m. This should work quite well at the 100+ ft height that our antenna will be installed at. The dipole runs parallel to the DB36’s boom and is attached to the element support trusses. The dipole uses the two end elements of the antenna as capacitance hats and a pair of loading coals to end-load the dipole. Its performance is just 0.8 dB below a full-size dipole on 80m. It also functions as a 60m dipole.

80m Dipole Loading

The 80m dipole attaches to an antenna switch which is mounted on the DB36’s boom support truss. This device enables the dipole to be switched in and out and matched to the feedline.

80m Dipole Switch

The single feedline to the antenna attaches to the switch and uses a pair of relays to connect the feedline to either the dipole or to the rest of the antenna depending upon which band is selected at the controller. The switch also contains a matching transformer and balun. A control cable runs from the switch to the main control cable connector box on the antenna. Note the knot in the control cable to keep it from being pulled out of the 80m dipole switch box.

Dipole Switch Internals

The final option to be installed on the antenna was the 6m Passive Element Kit. This kit adds two passive director elements to make provide a total of 6 elements on the 6m band. This improves the antenna’s gain and F/B ratio on 6m to 12.8 dBi and 27 dB respectively making it an effective 6m antenna.

6m Passive Element

The final assembly step was to complete the wiring of the main control cable and connect the controller to the antenna. Shown here is the main control cable connected to the Connector Junction Box on the antenna. The other end of the 24-pin shielded control cable connects to a DB25 Splice Connector which is attached to SteppIR’s SDA100 Controller. Note the two cable ties attached to the main control cable just inside the box. The cable ties act as a strain relief to prevent the heavy control cable from pulling on the associated connectors. It is important to carefully verify all wiring before connecting and powering up the DB36’s controller. We used DMM to verify continuity and proper connection of the control cable wiring. SteppIR also provides a document for troubleshooting which contains a series of resistance and short checks to do on each of the controller connections to the elements. It is important to do these resistance and short checks before you connect the controller for the first time as the miss wiring of the control cable can damage the controller if it is not corrected prior to power up.

DB36 Connector Box

After completing all of the resistance checks, we powered up the antenna and connected a feedline from the antenna to an antenna analyzer to check out the operation of the antenna on the ground. Before beginning the test, we enabled the 80m dipole and 6m passive element options in the controller. The next step is to run the calibration procedure on the antenna and then to individually run each of the elements out to its full length and check that each element motor is operating correctly and the associated element is fully extended. You can determine that an element is extended by gently shaking the element support tubes or sweep ends. If the element tape is extended, you will be able to hear it rattle inside the support tube.

With the elements checked out, we ran an SWR test on each band. The antenna is only 4 ft off the ground at this point so the minimum SWR reading on each band occurs about 500 – 700 kHz below the frequency settings on the controller which is normal. Also, the SWR measures higher than normal due to the antenna’s proximity to the ground.

DB36 Test Setup

What you are looking for is a pronounced “dip” in the SWR reading indicating that the antenna is Tuning to some sort of resonance. Shown below is the SWR measurement taken on 15m. In this case, the dip occurred at a frequency of about 300 kHz below the setting on the controller. All bands should be checked including 80m/60m (the dipole), the WARC bands (30m, 17m, and 12m) and 6m. It is also important that you switch between bands that are far apart and verify that the frequency of the SWR dip on a given band is consistent when the antenna is moved to a different band and back again. Any significant inconsistency between multiple readings on a given band indicates the unreliable operation of the antenna and needs to be investigated and corrected before the antenna goes on the tower. In our case, all of the tests and measurements checkout out fine.

DB36 Test SWR Measurement

The final step in the assembly of our DB36 was to attend to some details to ensure that the antenna is reliably on the tower. After carefully checking and making final adjustments on the boom and element support truss turnbuckles, we checked the tightness of the turnbuckle jam nuts and safety wired the turnbuckles to ensure that they will not come loose over time.

Safety Wire on Turnbuckles

We also added some additional coax seal where the control wires enter the element housings to ensure that this area is watertight. We did the same thing around the coax connectors on the Driven Element housing and the 80m dipole switch.

Control Cable Seal

It is also a good idea to check that all bolts are tight including the screws that hold the element housings to their support plates. I also checked that all of the electrical tape joints were smooth and tight. The final step was to remove the main control cable from the connector box and to tape a couple of cable ties and a packet of connector protector grease inside the connector box to make it easier to install the control cable and lock the box connector box lid closed once the antenna is on the tower.

The next step in our project will be to rig our 2m and 70cm Yagis on a test mast and test them prior to installation on the tower.

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

– Fred, AB1OC

First Tower Part 17 – Feedline Breakout System

September 21, 2012 by AB1OC

Feedline Breakout System

Since Anita (AB1QB) and I both want to operate at the same time, we are planning to put two SteppIR DB36 Yagis on our tower. These antennas will be connected to a DX Engineering Stack Matching System so that they can be operated together as a 4 over 4 array. The DXE Stack Match can select either antenna individually and connect it to the feedline associated with the array but it does not provide a breakout of both antennas onto separate feedlines. We designed and built a custom feedline breakout system to enable the simultaneous breakout of both antennas to separate feedlines. This project involved the construction of both a tower-mounted box to house a part of relays and a control box for the shack.

This device is inserted between the Stack Match and the antennas in line with the two phasing lines to each Yagi. It is critical that the breakout device provide identical impedance and phasing effects on both phasing lines if the array is to function correctly. To accomplish this, we selected a pair of Tohtsu Coaxial Relays (Model CX-800N) that have a very low SWR impact in the HF bands. These were installed in an outdoor utility box that we got from DX Engineering. Only one relay is used to break out the lower antenna to a separate feedline as the Stack Match can break out the upper antenna to the main feed line for the array. The reason that two relays are needed is to ensure that the RF performance of both phasing lines to the two antennas is identical.

Coaxial Relay

The relays require a 24V source to energize them. I built a simple control box for the shack to provide the needed control voltage. The controller includes three switches so that it can be used for additional 24V relay applications in the future.

Breakout Control Box

I wanted to be sure that the Breakout System had good isolation characteristics between the two phasing lines so that the device did not allow a transmitter using one antenna to interfere or possibly damage a transceiver using the other antenna. The relays we choose have good isolation characteristics which are a good start. To ensure that we have good isolation at a system level, I used an ArraySolutions Vector Network Analyzer (VNA) 2180 to measure the isolation between the various input and output connections in the Breakout System. The ArraySolutions VNA 2180 uses a PC and software to control a measurement unit that can perform one and two-port SWR, impedance, loss and phase measurements (many other measurements are possible as well). In this case, we are making a port to port loss measurement.

Isolation Measurement Setup using a VNA

The VNA 2180 has a dynamic range of about 100 dB which means that it can measure isolation up to this level. As you can see from the following screenshot taken with the VNA software, the isolation of the Breakout System is very close to the limits that the VNA can measure. The worst-case isolation measurement is about -97 dB on the 6m band. We also use Bandpass Filters when we are both operating and these filters provide an additional 55 dB or more of isolation which means we have a total of about 150 dB of isolation through this path. In the real world, the antennas themselves will likely have much less isolation between them than this so the isolation performance of the Breakout System should be more than adequate.

Isolation Measurement Results

We are making good progress towards the planned installation of three of our Yagis on the tower next week. I will provide some additional posts over the next several days covering additional aspects of the preparation for next week.

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

– Fred, AB1OC

Our HAM Station

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

Category Archives:

The 2012 CQ Worldwide Phone Contest

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 16 – Building Yagis (Second SteppIR DB36 Completed)

How Many Parts In A SteppIR DB36?

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

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

First Tower Part 15 – Building Yagis (SteppIR DB36 Completed)

First Tower Part 17 – Feedline Breakout System

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