ARRL 160M CW Contest 2015 from Lea Hutaff Island

ARRL 160M CW Contest 2015 from Lea Hutaff Island

For the past three years, I have operated the ARRL 160M CW Contest from Lea Hutaff Island, located off the SE coast of North Carolina.

This year, my campsite was located in the dunes, quite close to the beach.

AA4XX 160M Lea Island campsite

I noticed that the dunes just north of my campsite had been significantly overwashed by a recent prolonged rain event.  The sea oats had been stripped away from the ocean side to the sound side of the island.

Lea Hutaff Island overwash2 2015

The extended weather forecast was encouraging, with light to moderate wind and no rain for the duration of my trip.  I began setting up camp on Thursday morning and finished set up just before dark the following day. The 1KW Honda generator was located about 50′ from the operating tent, and I did not hear any trace of it while I was operating.

AA4XX 160M Lea Island generator tent3

 

I set up two antennas, a 48′ top loaded Spiderbeam vertical and a 135′ kite supported long wire. An A/B switch at the operating table allowed instant comparison between the two antennas.

I removed the top two sections from my 60′ fiberglass Spiderbeam pole and attached three 53.5′ top hat wires at the 48′ level.  This top loaded vertical was secured to an 8′ yard timber that was buried 3′ in the sand. The resonant frequency was 1810 kHz.

AA4XX 160M Spiderbeam vertical

 

The Kite vertical went up in two minutes flat!  The skyhook is a 9′ delta box, or delta conyne kite, which flies at relatively high angles and is a good lifter.  The lightweight teflon covered antenna wire was taped to the dacron tether line every 10′ or so, leaving plenty of slack in the wire.  The resonant frequency of the kite wire was 1805 kHz.

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AA4XX Lea Island 160M kite wire

 

A DX Engineering radial plate with 32 radials was positioned beside the 50′ Spiderbeam mast.  Half of the radials were 60′ long, and half were 120′ long. The radial system was shared by both antennas.

AA4XX 160M radial plate

 

An SCG-230 autotuner was installed at the radial plate, along with a multi tapped unun. The unun’s purpose was to transform the top loaded vertical’s low feedpoint impedance of 5 ohms to 45 ohms (1:9 ratio). The 45 ohm output of the unun was fed to the SGC-230 autotuner, which handled the varying reactance of the antenna system as I moved around the band.

AA4XX 160M Lea Island SGC230 autotuner

 

I decided to do something a bit different this year–operating in the QRP assisted class.  Assisted refers to the use of a local  or remote network to help with the spotting of stations that have not yet been contacted.

In my case, the spotting was performed by a QS1R SDR (software defined receiver).  The QS1R’s job was to listen to the entire 160M band during the time I was not transmitting.  The SDR works in conjunction with two software packages–CW Skimmer and N1MM Plus.  The end result was that my logging program was always aware when new stations fired up on the band, and by simply selecting one of those stations on the N1MM bandmap, my rig was immediately tuned to that station’s frequency, ready to make contact.  That is a huge benefit, because you no longer have to scan the band from  end to end to find fresh meat.

AA4XX SDR Lea Island

 

In the above photo, the QS1R SDR is on the left, and a Receive Antenna Interface (DX Engineering RTR-1A) is on the right.  The RTR-1A adds a second receiver port for my Argonaut VI transceiver, so the SDR can share the same antenna that the Argonaut VI is using.  A more complete explanation of this system will be the subject of a forthcoming blog.

 

Most of the radio gear was set up in my tent on a 3′ long camping table.

AA4XX 160M op station Lea Island

From L to R, equipment includes Powerwerx SS-30 Power Supply, homebrew controller for SGC-230 autotuner on top of p/s,  homebrew A/B antenna switch, Oak Hills WM-1 QRP wattmeter on top of ant switch, Argonaut VI transceiver, USB Winkeyer on top of Argonaut VI, Thinkpad laptop, N3ZN paddles (not seen to R of laptop)

Below table L to R, QS1R SDR, DXE-RTR-1A Receive Antenna Interface

That’s a lot of gear to haul to a remote location, especially when salt water intrusion and bumpy boat rides are a real concern.  I am indebted to my good friend and QRP buddy JP, AB4PP, who generously donated a Pelican case for my logging computer.  It’s waterproof and provides a high degree of shock protection.

AA4XX 160M computer pelican case2

Following up on this idea, I purchased a larger Pelican 1500 case, which provides safe transportation for most of the other radio gear.  The power supply and 3dB rx splitter are embedded in the foam beneath the Winkeyer and CW paddles, making this a very functional case.

AA4XX 160M station pelican case

The contest started at 5PM local time Friday afternoon.  It took me right up to this time to get all the radio gear and antennas checked out.  The good news was that all the gear checked out perfectly.  I was really  tired from two full days of work, but after a leisurely meal of reconstituted freeze dried food (sometimes pretty good stuff, sometimes rather horrible) I was anxious to see how the antennas measured up.

The kite vertical was again the winner this year by about 3dB for most stations, and by 6dB for some stations, despite the fact that EZNEC (antenna modeling software) predicted equal performance from these two antennas; The 48′ top loaded vertical was playing quite well, but it never bested the kite.  Speaking of the kite, I spent a couple hours late Friday afternoon making up a lightweight 30# dacron tether line, with 30AWG (very lightweight) teflon covered antenna wire loosely taped to the dacron line every 10′ or so.  With light winds expected Friday night, I wanted the kite to stay up as long as possible. This paid off, as unlike the previous night , the kite stayed up all night.

AA4XX 160M 9' delta box kite

I operated for seven hours Friday night before climbing into my sleeping bag for a few hours sleep.  By that time, I had 162 contacts in the log, with 51 sections, including 8 countries.  I was especially excited to work TI5W in Costa Rica, my first Top Band contact from that country.  My best US DX was W0SD in South Dakota.

Upon waking up and eating breakfast Saturday morning, I decided not to push myself too hard by operating all night Saturday.  Instead, I made the decision to start packing up in order to catch the mid afternoon high tide back to my home base, which was a one hour boat ride up the Intracoastal Waterway.

Packing up all my gear was not a trival prospect.  It took six hours to dismantle the antennas, radials, feedlines, camping gear and transport all the gear to my boat. The Spiderbeam mast  was dismantled within a half hour, including the time to neatly wind up the 6 guy lines and 3 top hat wires.  The Spiderbeam mast was secured to an eight foot yard timber with duct tape.  This made it easy for me to safely raise and lower the mast even in moderate winds.

AA4XX 160M vertical and kite

I had to be ready to leave before the tide got too low, or there wouldn’t be enough water to exit the tidal creek.  I got all my gear into the boat at high tide, so all was well.

AA4XX boat

In conclusion, I tell myself every time I return from one of these extreme trips that I need to seriously lighten the load for the next trip.  It’s a lot of work to pull off an operation like this, but it is also extremely satisfying.  Hopefully, I’ll be back next year with a couple like minded QRP friends, which will leave time to set up camp at a more leisurely pace and to more fully enjoy this lovely island.

4 thoughts on “ARRL 160M CW Contest 2015 from Lea Hutaff Island

    1. Hi Mark, Sure good to hear from you! It has been a while since we last QSO’d. I’m not sure if we have had a 2xQRP Top Band QSO either.
      I agree with you that using lightweight stranded wire is a critical factor in ensuring success. I started out using 100lb dacron kite line and 22AWG stranded antenna wire taped to the dacron line every 10 feet or so. This worked fine as long as the wind speed was at least 10 mph. As the wind diminished to 4-5 mph shortly after dark Thursday night, the kite sank to the beach. Fri afternoon I switched over to 30lb dacron kite line and 30AWG stranded antenna line, along with a lighter kite tail, which significantly reduced the weight and drag
      on the kite, allowing it to stay up all night, even when the wind speed was around 5mph. FB also on the phasing link you provided. Now that is really a blast from the past! 72 es HNY to you and your family.

    1. Hi Richard. Although the top loaded vertical is a proven good performer, I’ve found the quarter wave kite antenna to be the best performing Top Band antenna I have ever used. I’ve given some thought to building a phasing network for next year’s trip and combining it with two identical kite antennas spaced a half wavelength from one another. That would provide selectable bidirectional broadside or bidirectional endfire with additional gain over a single vertical. I conked out after seven hours of contesting Friday night, with a total of 162 contacts.

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