Archive for the ‘travel’ category

K8GU/5 Field Day 1B1Op Battery

July 1st, 2012

I found myself in Santa Fe, NM, for Field Day this year to attend a conference. As I have shared before, I have mixed feelings about Field Day, but this was a genuinely good time. I first checked ARRL’s Field Day finder map and the local club’s web site for activity. Zilch. So, I remembered staying at the Fort Marcy Hotel Suites on several previous visits to Santa Fe. These condos are up on a hill overlooking town. Across the street is Hillside Park, with a couple of scraggly trees that might be suitable for antennas.

Instead of bringing the “usual” portable station, I brought a Small Wonder Labs SW-40, a K1EL K12 memory keyer (assembled especially for this trip), Palm Mini paddles, a 40-meter dipole, and a AA battery pack. The whole station took up less space in my luggage than my notebook computer and set up in 15 minutes. I got the dipole center about 4-5 meters off the ground and the ends sloped down to about 2-3 meters high…just enough to allow cars and small trucks to pass under them in the parking lot. Apologies for the photographs…they were taken with my cell phone (which is a regular old “dumb” phone).

The SW-40 did not appear to be transmitting correctly when I first hooked everything up. So, I pulled the cover off (packing a Leatherman tool is another good reason to check a bag) and wiggled some wires around until it fired up. Not an auspicious sign.

But, I did manage to operate for about an hour and make 12 or 15 QSOs. They’re logged in a notebook, but I haven’t looked at it since making the contacts. Virtually every QSO was a struggle. Low power (1.5 watts), wrong band (20 meters would have been better), a low antenna, and the fact that I hadn’t used the SW-40 for any QSOs in over 10 years, conspired to make thing difficult. Most operators pulled me right out once I was in the clear and zero beat (which I think was a serious challenge with the slightly drifty and definitely touchy SW-40).

My final QSO was with my old radio club from my college days, W8FT. The operator was my good friend Bill, AD8P, who worked hard to pull me out once he got my call right. After I packed up, I noticed that I had a missed call on my phone…sure enough it was from Bill. So, I gave him a call and we talked for a couple of minutes. “When he answered the phone, he said, `New Mexico?!?! I told Kelsey (N8ET) that’s what I had copied.'” We had a nice chat as I hiked back down the hillside into town and he pulled into his driveway after his FD shift.

I don’t think I’ve ever been so delighted with a Field Day effort of so few QSOs (except maybe my first Field Day, which was much more work for about twice the number of QSOs). Including the walk from my hotel to the park, setup, tear-down, and operating, I think the whole exercise took about 3 hours, and was tremendously FUN.

1 comment »

Posted in radio, travel

Tags: joy of homebrew portable QRP

OAx/K8GU

April 3rd, 2012

Loyal readers know that from time to time, I am fortunate to travel to interesting and exotic locales for work—they usually come in pairs, so Greenland and Peru are it for a while. Although the motivation is usually field work, occasionally a conference pops up. The International Symposium on Equatorial Aeronomy occurs every three to four years and can be counted on for an exotic locale. Sarah had such a good time when we attended the 12th ISEA in Crete in 2008 that she insisted on attending the 13th in Peru with me this year. Of course, Evan complicated that a bit, and so we evaluated the pros and cons of leaving him with grandparents or bringing grandparents along, eventually finding a willing pair of grandparents to come along. If you’re interested in a general travelogue (and following posts) and some photographs, you might check out my father’s blogs. This short post is mostly focused on radio aspects of the adventure.

In retrospect, it may not have been such a good idea to bring ham gear to this meeting. Between being the most seasoned traveler in my family and the only one with a functional command of the Spanish language, plus Evan, plus hours of meetings and collaborations each day, there was little time/energy to actually operate. Getting to Peru was uneventful—we took an American Airlines codeshare flight on LAN Airlines via Miama to Lima and got there early in the morning. Unlike their neighbors to the south, Peruvian Customs is by far the most curious I’ve encountered while carrying radio gear—just a minor headache but Sarah was a bit concerned when they took me away for additional questioning. I carry modest gear—a Yaesu FT-840, Astron SS-30 (this should be replaced with something smaller, but it’s what I have), WKUSB, Palm Mini-Paddle, the K8GU portable antenna system, and various cables to connect it all up. After clearing Customs, we boarded a bus to Paracas, where the meeting would be held…

Paracas, which is about four hours’ drive south of Lima, was the site of a major earthquake several years prior and is still in recovery. The hotel that hosted the conference and a few nearby hotels had all been rebuilt from the ground up since the earthquake. The city is on a small bay that is protected from the Pacific. It’s very beautiful—desert sands that go right down to the bay. After a few days at the meeting, I managed to get the antenna set up.

One of the things that surprised me was an excellent JA opening on 20 meters just after sunrise before I went to breakfast and then the meeting. I am pretty sure it was a direct-path opening because the signals did not sound like long path and the long path crosses the southern auroral oval, whereas the direct path does not. (Auroral absorption, by the way, is one reason that the long path can be more effective than the short path.) Any time I called CQ as OA5/K8GU, I was greeted with a roaring pileup. Not bad for an antenna propped up on my veranda. Verticals on the beach rule, and this one wasn’t even really on the beach.

At the request of a friend, I made a special effort to operate on 12-meter CW in the afternoon. The portable antenna would not tune up on 12 meters with the wire radials I had laid out. In a moment of desperation, I assembled some extra pieces of my portable antenna to produce a tuned radial that I clip-leaded to the ground lug as depicted in the photo above. It worked right away and I was quite popular there as well.

A comment about computers—my standard work-issued computer is a MacBook Pro, which although perfect for my work, is essentially useless for amateur radio. I know this will generate a torrent of discussion, but if you are accustomed to real contest/DXpedition logging software available for DOS and Windows, you know that the stuff for the Mac doesn’t cut the mustard. I have logged DX operations on paper (CE/K8GU), or in the case of the OX/K8GU operation, brought along a second computer. However, in a long-delayed flash of insight, I bought and installed VMware Fusion on the Mac in February. It runs Windows XP and TR4W with the WKUSB just brilliantly and with no special configuration. Aside from having to press Fn+F1 to CQ, this was an epic win. KB9UWU tells me that there’s an option in VMware to eliminate this nuisance as well.

After the meeting in Paracas, we returned to Lima, where we celebrated the 50th anniversary of the Jicamarca Radio Observatory. The cornerstone of the Jicamarca facility is a 49.92-MHz radar that feeds an 18,720-element phased array, pictured above. Jicamarca is one of the most powerful radio transmitters in the world, capable of 4.5 MW output, and is used for a variety of atmospheric, ionospheric, and space science experiments. Like Arecibo, it was originally designed to perform incoherent scatter measurements of the ionospheric electron density profile.

Lots of fire in that wire! Have you ever seen a coaxial cable that’s rated for over a megawatt at 50 MHz? This is the feedpoint of the phased array. There are a few tuned stubs in there, too.

Here’s one of the four 1.5-MW transmitter cavities. A maximum of three are used together. When configured for three transmitters, the driver stage puts out 7 kW! Needless to say, everything is custom made on site. The transmitting tetrodes (8973s, if I recall correctly) are refurbished by the manufacturer as needed.

After Jicamarca, we went to Cusco, which is south and east of Paracas, and much more lush than the deserts around Lima and Paracas.

We spent a lot of time being tourists in Cusco and vicinity and I had some difficulty with my computer so I only made a handful of OA7/K8GU QSOs from Cusco on 17 meters. It is quite remarkable how much better the bands were from the coast. As someone who has operated from W3, W8, W9 and W0, I can attest to that difference as well. I missed my morning JA run…

A final thought—we drove through a lot of towns and communities in OA4, OA5, and OA7, on this trip. Nearly every town, no matter how small, had at least one building with an HF fan dipole on the roof. HF is alive and well in a mountainous country like Peru!

QSL information: If you worked OA5/K8GU or OA7/K8GU, the best way to get a confirmation is through ARRL’s Logbook of the World. I have been responding to direct cards (to my FCC address) with a one-day turn-around lately.

Comments Off on OAx/K8GU »

Posted in engineering, radio, travel, work

Tags: DX operating portable science

Review: The World’s Most Awesome Suitcase

March 23rd, 2012

Air travel is hard on luggage. Just yesterday, I was sitting on the tarmac at Washington National (DCA) as we waited for our arrival gate to become available. The ground crew were loading baggage into the departing aircraft and did not elevate the loading elevator quite enough. Several suitcases and a Pack ‘n Play (the technical, brand-inspecific term for these things is a “playard”…who knew?!) toppled blissfully off the end of the elevator and landed in a pile beneath the aircraft. That’s just the stuff you see…

Until recently, I managed to travel carry-on only most of the time, something that preserved the life of my inexpensive soft suitcase far beyond expectation. However, the proliferation of checked bag fees has caused thrifty passengers to stuff as much stuff as possible into their carry-ons, making the overhead bins a nightmare. My employer is willing to pay for the first checked bag when I travel for work, which is 90% of cases or more, so thrift is slightly less motivating for me. I suspect that checked-bag fees have also increased the size of the average piece of luggage, making it perilous for my small soft-sided bag. So, like U.S. drivers of 10 years ago who preferred gas guzzling SUVs for their “safety,” I decided to fight back with a hard-sided suitcase.

After a trip to Europe in 2008 in which one of our soft-sided suitcases was essentially destroyed, Sarah was on board with this idea. I proposed a Pelican case at the time, but she thought it was ugly and “looks like a toolbox.” Since it’s a well-known fact that women drive household purchasing decisions, it should be no surprise that we ended up with a set of highly-rated, yet inexpensive hard sided suitcases. After one or two domestic trips, one of these developed a crack. The trip to Greenland in January of this year was impetus for me to take matters into my own hands: I bought a Pelican 1560 (empty with no foam) and the 1569 lid organizer.

The genius of the 1560 is that you can’t load it to more than 23 kg with “normal” contents. Although, Sarah—and airline, security, and customs employees the world over—would argue that very little that goes into my bags is indeed “normal.” It’s only a little more expensive than a department-store suitcase and definitely cheaper than most of the high-end brands. And, of course, it’s indestructible…and it floats. What’s not to like about that? There is one downside—it is almost always loaded to near 20 kg, so it’s heavy. But, until the airlines force us to pay by the kg, I have my suitcase for life.

Upon return from our latest trip yesterday, the two larger hard-sided suitcases had big cracks in them. “I think all of our suitcases should be Pelican cases,” Sarah remarked as we left the airport.

Comments Off on Review: The World’s Most Awesome Suitcase »

Posted in travel

Tags: going broke saving money

A Portable Vertical Antenna

March 23rd, 2012

With the loss of my preferred frequent flyer status, airlines tightening their checked luggage allowances, and the addition of another traveler to the family, I’ve been contemplating a new portable antenna that is easier to pack than my usual DK9SQ mast and dipoles. I don’t do high-priced reduced-size antennas if at all possible since portable installations usually have other efficiency-reducing problems. Multi-element antennas take up additional space and have feeding and installation complications that are unnecessary for the casual DX operator. So, that leaves us to choose between a vertical and a dipole.

A few words about efficiency: Dipoles have a distinct efficiency advantage over verticals in almost every practical installation for 40 meters and up, except when the vertical is physically placed in or over salt water. Radiation efficiency tends to be dominated by near-field conditions, pattern is dominated by stuff that’s farther away. This is why vertical dipoles work so well for long-haul DX when placed within a few wavelengths of salt water. They don’t need the near-field efficiency enhancement as much as base-fed verticals, but they still leverage salt water for developing their far-field radiation pattern, especially at low angles required for long-haul communication.

I’m a casual DX operator, not a DXpeditioner, so I never operate on 160 or 80 meters. That is, considering the discussion above, why I have been using dipoles with the DK9SQ. But, verticals have a distinct advantage over dipoles in the sense that they are self-supporting. I decided to build a vertical because: 1) my next DX trip would include time near a beach and 2) I wanted to be able to bring my own support as I had with the DK9SQ.

My remaining requirements were now simple:

A vertical antenna that requires no additional supports. Guying is OK.
The antenna must be full-size (quarter wavelength) on 40 meters and above.
Experience has shown that multi-band operation is desirable, but instant band switching is not necessary.
The longest piece must fit inside my suitcase (20 in / 50.8 cm maximum length).
Field assembly and repair with only a Leatherman tool.
Minimum cost, minimum weight, minimum volume, minimum installation time.

And this is what I came up with:

There are 21 aluminum sections, most with a “swaged” (actually, a poor-man’s swage to be described in a moment) end and a slit end. They are shown here bundled perfectly inside a section of cardboard shipping tube. An 18 x 2.5 x 0.125-inch aluminum plate serves as the base. I used DX Engineering resin support blocks to insulate vertical from the base. A point could be fashioned on the bottom of the base and a foot plate attached to push into soft soil, but that has not been done.

Most sections fit together using overlapping joiner pieces that I previously referred to as “poor-man’s swaging.” I’m not sure that it’s actually a savings over paying a local shop to swage the ends for you when time is considered in addition to material, but I cut telescoping pieces six inches long and fastened them three inches deep in one end of a 17-inch section of tubing with two offset and orthogonally-placed aluminum pop rivets for a total length of 20 inches. This geometry not only fits in my suitcase, but results in a very small amount of wasted material as well.

The other end of each piece is slit about 2 inches and they mate with an all-stainless steel hose clamp. The first 10 feet of the antenna are 0.75-inch 6063-T832 tubing followed by telescoping sizes down to 0.375-inch at the very top. The transition pieces are a full 20 inches long and are slit on both ends. The full-size antenna will stand in a light breeze, but guying is a good idea. Guy rings are fashioned out of flat washers drilled in three places.

Tune-up is easy…the more radials you use, the less critical their length. After about 8 or 10, you’re in the clear here. I never attached enough to prevent them from affecting the tuning. If you only plan to have a couple of radials, go ahead and cut them to 1/4 wavelength (even though ground proximity will detune them). Then, set the length of the antenna using the required number of 17-inch sections (the 234/f formula is surprisingly close) with the last section being a variable length for fine tuning.

I’ve intentionally left out most of the details of the antenna itself because I don’t expect anyone duplicate it exactly. But, here are a few notes for anyone considering building one themselves:

There are lots of parts vendors out there. McMaster-Carr and DX Engineering will get you there in one order from each. There is a surprising amount of overlap in their inventories. Get the hose clamps from McMaster…even if you get stainless-stainless (stainless band, stainless screw), they are about 1/3 of the DXE price. On the other hand, the resin support blocks are cheaper from DXE.
I carry a compact antenna analyzer (Autek Research VA-1) with me. Field tune-up is a snap and it runs on a single transistor battery. It’s about 1/4 the size and weight of an MFJ-259 and good enough for amateur work. Oh, and I bought mine used for a fraction of the MFJ.
A tubing cutter is fine if you only have a half-dozen or so cuts. But, if you have a chop saw or need an excuse to buy a chop saw, it will make cutting the tubing far easier. My hands were raw for a few days after cutting the tubing by hand. I’m sure the antenna performs better on account of it, though.
Find a friend with a metal-cutting bandsaw to slit the ends of your tubes. I went through a half pack (McMaster mega-size pack) of cut-off wheels for my rotary tool doing my slits.
McMaster only sells the aluminum plate in 36-inch pieces. If you don’t have the aforementioned chop saw, an angle grinder with a cut-off disk does a surprisingly good job.
I pack a combination-screwdriver that has hex drivers that fit the hose clamps and #6 nuts. Even though the antenna can be erected with only a Leatherman tool doesn’t mean it has to be.
The small parts box shown in the top picture holds all of the parts for the antenna—it was 2 USD at Home Depot.
The final and most critical component is a clip-lead that can be used to attach various nearby metal structures to your ground plane. I have used it to make a temporary radial out of excess tubing sections on 12 meters as well.

That’s it. The antenna goes up in a few minutes, especially if not used at full length. I used it successfully last week as OA5/K8GU, which will be detailed in a future post.

Comments Off on A Portable Vertical Antenna »

Posted in engineering, radio, travel

Tags: joy of homebrew portable

A Winter Trip to Greenland

February 3rd, 2012

Last year, I managed to scrape together some equipment funds at work to buy a small spectrograph system for studying atmospheric light emissions (airglow and aurora). A co-worker secured the funds and contacts for us to install it at an observatory in Greenland. Because we need to make the measurements at night, and because the instrument was delivered in early December, we made immediate plans to go to Greenland as soon as possible. (Sarah is certainly laughing at this point because the plans were actually far from immediate and we bought our passage just over one week before departure.)

Greenland is only a short (4- to 6-hour) flight from the NE U.S., however the only route that operates in winter (and indeed the only commercial route) is on Air Greenland via Copenhagen, which operates four round-trip flights per week in winter. This turned getting there into a two-day affair of perverse travel arrangements totaling over 12,000 air miles to go about 4200 miles round-trip on the great circle. I met my co-worker, a United Airlines devotee (myself an American Airlines devotee), in Copenhagen and we flew to Kangerlussuaq (Sondrestrom) on Air Greenland.

One of the things that strikes you about Greenland as you approach Kangerlussuaq is how otherworldly and remote it is. Kangerlussuaq is the site of the former U.S. Sondrestrom Air Force Base, and one of two runways (the other is at Thule) on the island large enough to accommodate aircraft capable of flying to Greenland from abroad (this is a mild, although amusing exaggeration). Air Greenland has its hub there, shuttling passengers off to towns around Greenland on twin-engine turboprops like the Dash-8. It is, as our host explained, “…not your typical Greenland town. It is far inland at the end of the fjord and not on the coast. The only reason it exists is because of the airport.” Fuel and supplies are all brought in from outside. Like most current and former U.S. military installations worldwide, it is reliant on diesel fuel for its on-going existence. It’s sobering to be someplace that is totally unsustainable, although one might argue similarly of many U.S. cities, but I digress.

Kangerlussuaq is also near “the dog line,” north of which sled dogs are very common. Here is one of the two road hazard signs we saw while driving around…dogsled crossing:

The instrument set up easily the first afternoon and we were able to collect some data with it that night. As we were setting the instrument up, we heard reports of an Earth-directed CME from the Sun and hoped for aurora over the next few days. We were not disappointed…

The second night, I stood “aurora watch” in the cold while my warm-blooded co-worker processed the previous night’s data. Soon, I saw some faint cloudy white sheets way down on the horizon and I ran back in to alert him and retrieve the camera tripod. This photograph was taken facing toward the east southeast.

And, the 3.5-MW peak L-band incoherent scatter radar was running. The dish is blurred because it is moving.

And, here is a shot of my fan dipole strung up on the DK9SQ mast.

Speaking of radio, I did manage to make a few QSOs as OX/K8GU on 17 meters, but not as many as I would have liked. The combination of high absorption in the auroral oval (mostly to our south during our stay), little sunlight, a poor low-angle shot (required to avoid the auroral zone) to North America, short openings, and the fact that we were well-occupied with work for the four days we were there conspired to keep my contact count low. QSOs will go into LoTW soon—the certificate was issued yesterday. I have not yet designed a card, but there will be a special card. Thanks to those who did contact me.

Comments Off on A Winter Trip to Greenland »

Posted in hobbies, radio, travel, work

Tags: science

DXpedition QSLing

November 1st, 2011

This post might better be titled “supporting things that you value.” A recent large-scale DXpedition to a “new one” just started sending out QSL cards in the past few weeks. I have seen a bit of traffic leaking onto the regional contest club’s e-mail reflector about QSLing this operation and today someone complained that QSL requests that included donations were being processed rapidly and that he had not yet seen his. He was thoroughly chastised by a number of people on the reflector (including one of the DXpedition operators who went on at some length about the cost of the DXpedition) before the thread was (wisely) quashed by the moderator.

I composed a short reply very early in the melee, but decided (also wisely) not to contribute it because it really had little to do with contesting. So, I’m writing here in hopes that someone finds it interesting.

When I was a new ham, I won a copy of the ARRL Operating Manual at a hamfest. It sounds inane now, but I read the thing cover to cover. In the chapter on DXpeditions, the author writes, “A donation should never be a condition for receiving a QSL card.” That has stuck with me through the years. The fundamental question is: why spend tens of thousands of dollars on the effort only to hold the operators who worked you hostage for a donation that might cover your QSLing costs if you’re lucky?

But, life is rarely black and white and most DXpeditions understand the futility of that question, so the situation outlined above rarely happens. In the present scenario, the DXpedition stepped into the gray by prioritizing donors ahead of non-donors. I have no problem with this. In fact, as I began to write in my reply, it is a matter of supporting things that are important to you. If having a card for the “new one” is important so you get on the Honor Roll for this year’s DXCC Yearbook, how much is that worth?

This falls into the same category as people who used to complain about the results of contests sponsored by CQ magazine being unavailable for free online. Well, if you want the results, buy the magazine!

Enough ranting…did somebody mention that CW Sweepstakes is this weekend? SWEEPSTAKES!

3 comments »

Posted in hobbies, life, radio, travel

Tags: contests days o' yore unobtanium

Wallops Island SuperDARN

February 21st, 2011

A few photographs from work on the Wallops Island SuperDARN radar last week…

Comments Off on Wallops Island SuperDARN »

Posted in engineering, nature, radio, travel, work

Tags: science

Recent tinkerings (9 Jan 2011 edition)

January 9th, 2011

Several people have commented over the years that I should “write more” on the blog. I usually respond that I could spend my free time tinkering/hamming or blogging, but not both. Here are a month’s worth of blog posts as freestyle poetry:

A section on my workshop has been added to k8gu.com under Engineering.
Discovered that although the SoftRock VHF Ensemble II won’t fit (barely) into the Bud CU-473 diecast box I bought for it, it will fit into an extruded enclosure that housed an ancient X-band radar detector I picked up at Dayton in 2002 in hopes of stripping the Gunn diode assembly and getting on 10 GHz. Bonus points for thriftiness. Photos will follow once I finish the project.
Did not observe Quadrantid meteor pings with the SoftRock VHF Ensemble II, but did notice something interesting about the W3APL beacon. Need to investigate.
Have more CE/K8GU QSL cards again, finally. Tonight, I might finish the bureau (and, ashamedly one direct) cards languishing. Some K8GU (and AA8UP, no kidding) bureau cards are sitting here staring at me, too. Not a big project, though.
Operated the NAQP CW on Saturday (8 January 2011) for four hours and twenty minutes and made 318 QSOs x 128 multipliers for 40,740 points before log-checking discounts. This total is pleasing to me especially considering that it was almost all leap-frogging SO2R search-and-pounce, which can be very fatiguing. It’s fun to see the rate meter stay over 100 when you’re S&Ping. Good Sprint practice.
Still the best 30 minutes on the radio every week: I operated the NS Ladder on Thursday (6 January) night and made my customary 30 QSOs x 24 multipliers for 720 points. Hopefully, adding 160 will give me some momentum to increase this score back over 1000.
We had a spell of 50F (10C) weather on New Years’ Eve. So, I put the 2-meter beam back up on the chimney. It was formerly mounted on a steel mast that was ratchet-strapped to the chimney. A strong wind (>50 mph gusts) before Christmas bent the mast (actually a fence top-rail) and I had removed it. I cut the bent lower portion of the mast off and attached the remaining top portion with rotator to a “girder” constructed from two pieces of treated 2″ x 4″ x 10′ lumber joined with a half-dozen lag screws. Again, I ratchet-strapped the entire assembly to the chimney. The present configuration is much stronger and less prone to damage. The 3-element 50-MHz Yagi is still on the ground until I actually get the transverter finished, which should be soon (as it has been for 12 months now).
Repaired a SoftRock v6.2 downconverter for WF1L and learned that you can solder leads back onto SOIC packages if you’re careful.
Have had delightful exchanges with KN6X and ZL1CDP about repairing the TS-930S. Some of these discussions (and their fruits) may make it onto the site at some point.
Back in December, I started integrating the W1GHZ transverters using UT-141 semirigid jumpers with pre-installed SMA connectors obtained on attractive terms from Max-Gain Systems. Mitsubishi RA18H1213G (1296 MHz) and RA30H0608M (50 MHz) modules arrived from RF Parts. May have a lead on something less expensive with more gain for 903 MHz via HA1AG. The big remaining tasks in all three transverter projects are the sequencer and IF interfacing.
Also in December, I had dinner with NS Ladder father Bill, N6ZFO, in San Francisco at the Hyde Street Seafood House & Raw Bar, which is a favorite of NA Sprint father, Rusty, W6OAT. Yes, I did feel that I was in the presence of greatness. (I had their excellent pork chops since I’m not into seafood, especially raw seafood.) Like most contesters, Bill’s a super, fascinating guy apart from his radio contesting interests.

Comments Off on Recent tinkerings (9 Jan 2011 edition) »

Posted in engineering, hobbies, life, radio, site, travel

Tags: 50MHz cheap VHF contests repair ts930 W1GHZ

QRL for Sprint and September VHF

September 16th, 2010

As I mentioned previously, I was planning to make the NCJ North American Sprint and the ARRL September VHF contests my kick-off to the Fall/Winter contest season. When a work trip was scheduled for that weekend, I assembled my portable station. But, Sarah convinced me not to take it since carrying the ham gear always complicates travel a little bit. Since the work trip was radio-related, I thought I’d share a couple of pictures and stories.

One of the projects in which I participate is the middle-latitude expansion of SuperDARN (Super Dual Auroral Radar Network). SuperDARN is a global HF radar network that is used to monitor plasma processes in the polar ionosphere/magnetosphere. It was recently highlighted on QRZ.com. Last year, we built a pair of radars near Hays, KS. This year, two radars are under construction in central Oregon. I went out to assist with the initial phases of the build.

The radars are installed on an old HF over-the-horizon-backscatter (OTH-B) radar transmitting site in Christmas Valley, OR.

Two of these radars were constructed for the U.S. Air Force as an early-warning system for aircraft, one in Maine and one in Oregon/California. The western portion of the radar was only turned on briefly for testing before being relegated to “warm storage” and then decommissioning. Typical. None of the antennas or transmitters are still on site and a lot of the copper wiring has been looted. Everything left inside the building, including the backup generator, was in essentially mint condition. As an aside, the transmitters from the Maine site were recently installed at Arecibo Observatory. I have no idea what happened to the transmitters from this site. Despite the fact that the antennas and transmitters were missing, there were a number of interesting things to see.

This OTH-B radar was a megawatt class (output, not ERP) system split into three segments/sectors, facing NW, W, and SW, each fed by four transmitters. Each sector had a separate, dedicated 3-phase power line that came from a substation some 50 miles away—I found it on the way home. You could follow the poles straight to it if you knew what you were looking for. Each of the transmitting arrays was surrounded by a fence, for obvious reasons. The fence was made entirely of wood. Furthermore, almost all of the washers were a fiber material, not galvanized steel like the bolts.

At first, I thought that the washers might have been an electromagnetic consideration, like the wooden fence, which might have distorted the antenna pattern in the best of cases or simply melted in the worst. But, I suspect now that it was a mechanical consideration to deal with dramatic changes in temperature and humidity in central Orgeon’s Great Sandy Desert.

The actual construction of the SuperDARN radar is not that exciting at this point, but here are some of the 72 aluminum poles we dressed with cables for the two radars. Each radar has a 16-element phased-array of folded dipoles mounted in a corner reflector. I installed a lot of N connectors on LMR-600 and a lot of Preformed end-grips on Phillystran, in addition to some more cerebral tasks.

The site has good optical conditions, too. So, I’m looking forward to trying some of my optical instruments out there. Here’s a quick star-trail exposure I took with the camera propped up on a picnic table in the motel parking lot.