Tag Archives: hf

2014 IARU HF World Championship

The results from the July, 2014 International Amateur Radio Union (IARU) High Frequency (HF) World Championship contest were published. WA4NZD placed first in Alabama, in the Single Operator, Mixed-mode (phone & CW), Low Power category. World-wide the club placed #2507 out of 5181 participants. The club earned a score of 32,480, with 152 QSOs and 80 multipliers. The operator was WA2JQZ.

KB5EZ also participated in the contest from his home. He placed third in Alabama, in the same category.

Detailed scores (see Page 14 for WA4NZD):
http://www.arrl.org/files/file/Contest%20Line%20Scores/2014/2014_IARU_Printable_Line_Scores-19_Jan_2015.pdf

ARRL Contest Database with contest article:
http://www.arrl.org/contest-results-articles

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Hexagonal Beam Antenna Presentation by Rob Conklin N4WGY

At our last meeting earlier this month, we were treated to an excellent talk about Hexagonal Beam antennas, or Hex Beams,  by Rob Conklin N4WGY. Rob is a local ham, a mechanical engineer, and a home brewer.  He introduced to us what the Hex Beams are, how they perform, and how they are constructed. And he shared his home brewing experience of building one for himself. He showed us how relatively easy they are to build.  It was such a good talk, and a good source of information, that I would like to highlight what he shared.

These are some attractive characteristics of the Hex Beam.

  1. They are relatively low-cost directional antennas compared to the regular multiband Yagis, and don’t require large towers.
  2. Compared to the regular Yagis, their profile provides lower wind loading, and they are relatively more stealthy.
  3. They are relatively light weight (~25 lbs) and small (~22 feet diameter).
  4. They perform well. Their gain and front/back ratio are comparable to the regular 2-element Yagis. They will work well if just above the roof. They are typically HF, and for HF many of the measurements don’t require tight tolerances. They have about a 3 dbi gain over dipoles.
  5. You can buy commercially made Hex Beams.
  6. But they also are very conductive to home brewing.  Good selections of commercial parts and kits are available.  You don’t need fancy tools nor a lot of skill.
  7. You can get up to 6 bands without traps and without a tuner.  They are relatively easy to adjust.

Hex Beam Design

When I first saw Hex Beam antennas, I was confused because I couldn’t immediately distinguish what their many elements were for. But actually their basic plan is simple.

If it is a monoband antenna, it is just a 2-element wire Yagi system, with a driver and reflector. The wires are supported by what looks like an upside-down umbrella structure.  The structure consists of 6 spreader arms mounted radially from a central base-plate, and a straight center post also mounted from the base-plate. The wires mostly follow the spreader arms’ hexagonal shape.  The driven element wires are supported by one half of the upside-down umbrella, the reflector is supported by the other half.  The spreader arms are structurally supported at their open ends by Dacron tension cords connected to the top of the central post.  Two Dacron cords also run between two spreader arms on the front driver side of the antenna, to maintain correct separation.  The central post contains a 50 ohm coax feed.  A mast mounted to the bottom of the base-plate can be rotated to direct the antenna.

Hex Beams are often multi-band antennas, with up to 6 bands. The multi-band antennas have individual 2-element wire Yagi systems for each band, stacked as you go higher up the umbrella. The 6-band Hex Beam that Rob built operates 6, 10, 12, 15, 17, and 20 meters. The shorter wavelength 6 meters antenna wires are the lowest, where the distance between spreader arms is least.  20 meters wires are the highest.

And so unlike the regular Yagis which use trap coils to operate on multiple bands, the Hex Beam design just utilizes separate wire sets for each band.

This is Rob’s antenna on the roof at his home.

Hex beam antenna on Rob's roof.

Hex beam antenna on Rob’s roof. The front driven element side is facing us.  Click to enlarge, click “back” on your browser to return.  [Courtesy N4WGY]

Classic and G3TXQ Hex Beam Versions

Rob discussed two designs of the Hex Beam. The original classic version was manufactured by Traffie Technologies, and then copied by many home brewers. Rob said many hams use it and swear by it. But it has two performance shortcomings.  First, it is narrow banded; that is, if you tuned the antenna length for the SSB portion of the band, its SWR might be too high at the CW end. Second, if front/back selectivity is peaked, the SWR is no longer optimized. And so that front/back selectivity had to be compromised.

The shortcomings were overcome in 2007 by Steve Hunt G3TXQ. After extensive modeling and experimenting, he developed a modified design that corrected both problems and gave the hex beam better performance: The G3TXQ design has good SWR across the full ham bands.  And the peak front/back ratio is at the optimal SWR.  With a slightly simpler wire system, it is also is a little easier to build. Rob built a K4KIO version of the G3GTX design.

In both the original and G3TXQ designs, the layout of the driven element wires is similar.  The driven element layout is shaped like an “M”, or more precisely like two “V”s.  One end of each “V” starts from the feed connection at the central post, extends to a spreader arm, then continues as a side of the hexagon to the next spreader arm.  Spacer ropes clamped at the spreader arms keep the wires in sufficient tension.

Schematic top view of G3TXQ Hexbeam antenna

Schematic top view of G3TXQ Hexbeam antenna. [Courtesy N4WGY]

The other end of the spacer ropes connect to the reflector wires. The spacer ropes keep a critical separation distance between the driver and reflector elements. The lengths of the wire elements and the spacer ropes are the critical measurements to make for the hex beam.

In the original design, the reflector wires had also followed an “M” shape configuration. In the G3TXQ design, however, the reflector wires follow the hexagonal shape provided by the spreader arms.

Performance

As Rob points out, the G3TXQ design provides good SWR performance across the full range of each ham band. He showed us a spectrum analysis of his antenna.

Full SWR scan of N4WGY's hexbeam antenna, from 1 to 36 MHz (160 to 10 meters ham bands). [Courtesy N4WGY]

Full SWR scan of N4WGY’s hex beam antenna, from 1 to 36 MHz (160 to 10 meters ham bands). The grey columns are the ham bands.  Note the SWR dips where this hex beam is designed for: 20, 17, 15, 12, and 10 meters. The antenna is also resonant for 6 meters (50 MHz), but the analyzer doesn’t reach that high a frequency.   [Courtesy N4WGY]

 The chart shows the SWR performance of his Hex Beam, as the frequency varies from 1 MHz at left to 36 MHz at right.  The shaded columns are the locations of the amateur radio bands.  For the bands not designed for, 160, 80, 40, and 30 meters at left, the SWR values are well above 3:1.  But at 20 meters the SWR dips to about 1.2:1 and is well below 2:1 across that band. The SWR for the other ham bands designed for also remain below 2:1 and in some cases also dip to as low as 1.2:1.   You can click the image to see the details for each band. You can see Rob made his lengths slightly long, but he can adjust that, to better position the dips within the ham bands.

Rob brought in to show us the antenna analyzer he used to scan his antenna and make the chart.  This analyzer connects through a USB cable to a computer, where the scans can be displayed, zoomed in for details, and saved.  The analyzer is made in India as a kit and costs under $60.  The analyzer is called a Fox Delta AAZ-0914Ahttp://www.foxdelta.com/products/aaz-0914a.htm.

Rob mentioned that he can reliably make contacts around the world, when propagation permits.  And he feels comfortable competing with hams with larger antenna systems.

Construction Tips

Rob Conklin N4WGY presenting at our meeting [Photo courtesy NM4T]

Rob Conklin N4WGY presenting at our meeting, here discussing construction details. [Photo courtesy NM4T]

Rob devoted much of his talk to construction details, and much of the Q&A from the group was about components and building. I will mostly defer to the online resources Rob suggested. But Rob did give some additional advice:

  • Don’t use PVC for the center post.  Especially in the South with UV from sunlight, the material will quickly degrade.  Spend the extra money to get UV resistant tubes.  He recommends buying online the mast sold by K4KIO.
  • For the wire sets, he says 14 AWG stranded/plated and uninsulated antenna wire would be best.
  • Telescoping fiberglass poles are recommended for the spreader arms.
  • Do not make the wire elements too tight.

Here are resource links.

Construction plans:

  • http://www.hex-beam.com/ – The K4KIO website with detailed, step-by-step construction plans, similar to what Rob showed us.

Supplies and commercial hex beam kits:

SWR scanner tool:

Addendum

For the close of the talk, Craig Behrens NM4T brought in to show us a light-weight, self-contained, portable G3TXQ hex beam antenna. It is designed and manufactured by a company in Germany called Folding Antennas.  The antenna weighs only 9 pounds, is collapsable to 45 inches, and comes in an easy-to-carry bag. Instead of folding out like an upside-down umbrella, the spreader arms fold out flat.  The flat configuration has much less bending load, and therefore the spreaders are made thinner and lighter.  The wires have special fittings to attach to the poles. The antenna can be assembled by one person in 10 minutes. [See http://www.vibroplex.com/contents/en-us/d3.html. ]

Craig also showed us a prototype TenTech Patriot QRP transceiver.  It operates SSB, CW, and digital modes on 20 and 40 meters at 10 Watts.  Its design was influenced from recommendations by his QRP Skunkwerks group.  During the following week Rob Suggs KB5EZ (one of the members of that group) gave it some field testing.

 

The club again thanks Rob Conklin N4WGY for giving us an excellent practical, educational presentation.  The club also thanks Craig Behrens NM4T.  And thanks to our members and guests for participating.

One of the eQSLs the club recently received shows a hex beam of KL2R, the Two Rivers Contest Club in Fairbanks, Alaska. You can see the wires in front of the aurora.

QSL card we received from KL2R in Fairbanks, Alaska, showing their hex beam at night (with aurora).

QSL card we received from KL2R in Fairbanks, Alaska, showing their hex beam at night (with aurora).

We earned a First Place award again!

The results for the 2014 ARRL International DX Phone Contest were just published. WA4NZD scored First Place within the Alabama Section, in the Multi-operator Single Transmitter Low Power category!

The contest was during the first weekend in March 2014.  We operated Friday night, Saturday and Sunday.

Our point score was 43,605, with 168 QSOs and 95 multipliers.  Within the global community we placed #2015 out of 4102 entries.

It is still too soon for us to receive a certificate.  We only learned the news by carefully checking the just published online article, ARRL International DX Contest – Phone 2014 Results .  You will see us on page 20, the Regional Leaders by Category Page, under the Southeast Region column.  The results are grouped by categories; we are with the MSLP (Multi-operator Single Transmitter Low Power) group.  The others shown in that group are other state leaders in the Southeast Region for that category: N4XI (VA), AJ4DT (FL), WA4NZD (AL), and WA1F (GA).  We weren’t in competition with the “heavy hitters” of these contests, who typically run scores above a million.  We are in a niche of our own.

Our operators who accomplished this were Matt KA0S, Rob KB5EZ, Kalen KK4KLT, Don N4MSN, and Gary WA2JQZ.  Rob, Kalen, Gary, and Matt operated Friday evening.  This was Kalen’s first contest.  Don operated on Saturday*.  And Gary came back on Sunday.

For us this was a chance to operate and practice our skills, and have some fun in ways that don’t come every day.  Many other hams around the world participate.  It is fun to meet them, and in doing so to recognize that the world is really a diverse place.  With many hams on the bands from so many places, you can notice propagation conditions and how those change over time.

We operated on 10, 15, and 20 meters, and just briefly (for 4 QSOs) on 40 meters.  10 meters was fortunately wide open for parts of the late afternoons.

We significantly increased our DXCC credits with this contest.  Some of the stations that gave us first-time Logbook of the World (LOTW) confirmations for their countries were JL1SAM (Japan), TF3W (Iceland), J75Y (Dominica), LX7I (Luxemburg), YS1/NP3J (El Salvador), HC2AO (Ecuador), and TO5A (Martinique) — to name some which quickly stand out in the record.

As we are not in competition with the “heavy hitters”, our contest operations are relatively relaxed.  Such activities make good learning experiences, no matter how much or how little experience you have.  Because hams of different experience levels and interests operate, they each will make different decisions, based on their needs and how they perceive their situations. Everyone influences what happens.  And so you get a richly diverse environment.

We’re in a unique niche to get such an award.  Nonetheless it reflects genuine and good things about us.  Congratulations to all of us!

– Gary, WA2JQZ

 

ARRL DX SSB Contest 2014

Rob KB5EZ and Kalen KK4KLT warming into the contest as it started Friday evening. This was Kalen’s first contest.

ARRL DX SSB Contest 2014

Rob KB5EZ at the mike with Gary WA2JQZ logging.

ARRL DX SSB Contest 2014

Matt KA0S at the mike, working the contest into late Friday evening. Don N4MSN continued working the contest on Saturday. And Gary WA2JQZ returned on Sunday afternoon.

* PS note — That Saturday, March 1st, was the Birmingham Hamfest. Rob KB5EZ and Gary WA2JQZ drove there with Craig Behrens NM4T and Jim Spikes N4KH, and they had an extra adventure of their own. Craig gave two forums based on his Caribbean DXpeditions. Besides participating in the hamfest, on the way back they stopped at an I-65 rest stop south of Culman, and operated QRP CW and JT65 until dark. The ARRL DX contest was only for phone, and so, operating CW and digital, they didn’t participate in the contest from the field. Malcolm K4MLP also attended the Birmingham Hamfest.

***

ARRL DX Phone 1st Place Award for Alabama Section, Multioperator, Single Transmitter, Low Power

ARRL DX Phone 1st Place Award for Alabama Section, Multioperator, Single Transmitter, Low Power, for 2014

Field Day 2014 is here .!.

Has it really been a whole year since Field Day ?
(updated 20140629)
The club has had a lot of activity getting ready for the summer contest season, and this weekend will be a focal point. I wanted to start a new post, and let everyone know that WA4NZD will be active in the “1F” category, as our facility at NASA/MSFC is an informal auxiliary EOC that exercises to support both the Marshall and the Redstone communities. We will run one transmitter, which covers 160m thru 6m. We will also have an active VHF station to cover VO-52 satellite, 50MHz, 144MHz, 432MHz.
Surely you can find us somewhere. Work us everywhere you can.

Oh, and to find us, if you already have access to the base – please drop by to see whats a goin on. https://wa4nzd.wordpress.com/2010/05/05/quick-maps/

We hope to come back and update this post thru the weekend, so check back.

UPDATE: 20140629 – back for more . . .

The log indicates that KA0S was here until 03:45 local, and I was back at 08:15 after leaving at 01:00 CDT. WA2JQZ got here at 09:30, with fresh muffins and coffee. N4CNY just arrived as well, and is going to listen on 6m. Only one contact on 6 this morning, from Texas, and 2 meters has only been a little noisy.

20140628_4227ax

N4MSN, W4VM, KK4RPQ, KK4TJP, N4CNY, WA2JQZ, WB8ELK, N5AYD, WB5RMG

We had a pretty good crowd at times last nite, several distinguished guests.

20140628_4222acx

CW contact with W3CWC, via VO-52

Field Day dramatically increases the challenges, even for CW via satellite. WB8ELK finally pulls one out on our second VO-52 pass just before it goes LOS over the Pacific Ocean. WB5RMG makes sure it logged. Thanks to W3CWC for that contact, worth 102 points for us (including the satellite bonus) .!.

Another update to come later…
Thanks /;^)

June is a busy month

There are several events in the month of June for the ham radio world. Two of my favorites are the ARRL June VHF QSO Party, and the annual ARRL Field Day. The MSFC Amateur Radio Club participated in both activities this year. Here are some pics in a gallery (click one for the slideshow) . . .

Here are some links to more pics from WB5RMG for June 2012 activities :
GigaParts celebrates Ham Radio Day in Huntsville AL.
Full photo gallery for WA4NZD club activities for June 2012.

Don’t forget, we also have a monthly meeting, gathering ~4pm CDT, 2 Aug 2012. The short meeting typically starts by 5pm in Bldg 4622. Click for maps.

Thanks  /;^)

Now we have 2012

Time to start another year .!.

Sometimes it seems like we didn’t do much as a club, but just look back on this last year in the blog, and you will find NanoSail-D, VHF contests, Field Day, the Final Shuttle Launch Special Event, and points in between. We have come a long way in bringing the MARC back to life, and can be proud of that. We logged over 250 HF contacts during the STS-135 commemorative, and have sent certificates to all stations who sent us a SASE. The eQSL logs for this last year’s events will be uploaded before long, so please be patient.  /;^)

Sure we have a ways to go – but we already have plans in place to replace the HF beam rotor, and get our satellite tracking hardware back into operation. We need to focus our attention and get our Continue reading

STS-135 launch

STS135 Mission Patch

STS135 Mission Patch

WA4NZD will operate from NASA‘s Marshall Space Flight Center‘s club station after the launch of Atlantis to celebrate and commemorate STS-135, the final flight of the space shuttle program. The launch is currently scheduled for Friday morning, July 8th, 2011. This station Continue reading