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ARRL DX with the K2

February 16th, 2014

k2100

One of the goals I had for the K2 that I failed to mention in the previous post was to fill-in for the K3 in DXpedition service.  This is a tall order.  It also necessitated upgrading the basic K2/10 to a 100-watt K2/100—being loud (enough) is an important part of pileup control.  I had the good fortune to come across an already-assembled final amplifier unit at an attractive price a few days after I purchased the radio.  I took that as a sign!

Another rite of passage for the K2/100 would be…how does it perform in a pileup?  One of the really great things about ARRL DX CW since the advent of the CW Skimmer and Reverse Beacon Network is that literally any U.S. station (especially on the East Coast, my Western and Midwestern friends will remind) with a modest signal can elicit a blistering run of Europeans.  I’ve been relatively unhappy with the K3’s response to pileups, with callsigns often being mushed together more than with other radios (e.g., the TS-930S).  I understand that tailoring the K3’s AGC should help this—the KE7X book now graces my shelf but I haven’t had a chance to explore all of his suggestions yet.  Having heard anecdotally that the K2 does better in this regard, I was excited to break it in with ARRL DX.

Sarah worked this weekend and I was frankly wiped out from a full week at work plus shoveling 18 inches of snow and cutting up trees from the previous week’s ice storm!  Nothing approximating a “full” operation was in the cards.  In about two hours of operating, mostly on Sunday, I made about 140 QSOs on 10 and 15 meters.  I’m happy to report that the K2 did quite well with regard to the pileup response and I didn’t manage to break it CQing hard at full power.  The K2 also passed the “W3LPL test”…Frank lives just a few miles away and is frequently quite loud here.  But, I could still hear nearby stations with no problem at all.  The one thing that disappointed me about the K2 is that it seemed a little deaf as the 15-m band was closing to Europe.  A number of stations were right at the noise floor and were tricky to copy.  This might have been “one-way” propagation, too, a topic I should write about at some point.

The upshot is that I’m extremely pleased with the K2 and I look forward many more QSOs with it!

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Latest Tinkering (or how Elecraft is taking all my money)

January 28th, 2014

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On Christmas Eve, I was sitting at my in-laws’ kitchen table with the Small Wonder Labs SW-40 I built as a high school kid in 1998 listening to beautiful music and I got the itch to come up with a radio smaller (and less expensive) than the K3 to drag around with me when I go places.  My mind wandered to the NorCal Sierra, which was a featured project in ARRL Handbook’s of my youth.  I was able to come up with a draft version of that Handbook article on the web—pause for a moment and think how revolutionary that is—my in-laws don’t have an ARRL Handbook, let alone the one that contained the Sierra article.  I looked at the bill of materials and realized that I had some 70% of the parts in my junkbox.  This seemed like a good idea until I went searching for a PCB.

Why PCB?  Well, I’ve done the dead-bug thing and it works great but it’s a pain to troubleshoot and unless you have decades of experience doing it, it looks like a Mexico City suburb, sprawling unpredictably in every direction with only the most tenuous connections to the core.  Since I was seeking a travel radio, I wanted it to be compact, easy-to-troubleshoot, and relatively rugged.  Due in no small part to the wishes of the Sierra’s designers (not coincidentally founders of Elecraft), boards are no longer available.  I looked into doing my own board, but if you don’t mix chemicals yourself, you’ve suddenly spent $150 on PCBs, plus the layout effort.  I toyed with making the board smaller (a win in several ways) by using surface-mount parts but even that was a non-starter since my junkbox parts are through-hole, requiring me to buy everything.

Astute readers can extrapolate what occurred next.  I went to the Elecraft web site to price the Sierra’s successor, the K1.  I had all but made up my mind to sell off some junkbox items and raise the capital to buy a K1 kit when something occurred to me:  fellow ham blogger Mike, VE3WDM, had recently moved to a smaller QTH and was offering a half-completed K2 kit for sale.  His asking price was only a little more than the K1 kit with some of the options I wanted and it was all-band.   The ad had been posted for some days by this point, so I fired off a sheepish e-mail to Mike asking if the radio was still available.  It was.  We sealed the deal and the radio made the somewhat tortuous ride (for us, not the radio—it sat in Chicago for two weeks) from his QTH to mine via the postal system.

I would not have bought a partially-finished kit from just anyone.  However, since this was Mike’s second K2 build and he was documenting it carefully in a blog, I figured it was a pretty safe bet.  So far, that is definitely true.

While I was eagerly awaiting the radio’s arrival, I redoubled my efforts to get a friend’s TS-930S off of my workbench, a task that involved replacing all 115 electrolytic capacitors on the cookie-sheet-sized “Signal Unit” board (similar to the K2 and K3 “RF unit”).  That radio still has low drive (it has ALC again and sounds like a million bucks), something I traced to a hard-to-find semiconductor that’s now on-order.  So, I gathered it up and started work on the K2 on Sunday afternoon.

Last night, I got it on 40 meters RX-only and peaked up the RX BPF.  Former K2 owner KL9A mentioned to me that it has some blow-by on strong signals but that he thinks it’s a pretty good radio.  I can confirm that based on my experience last night.  It sounds really really good on CW.

More on the build to come…including a look back at some troubleshooting of the BFO circuit.

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Still Alive

January 1st, 2014

Despite the lack of activity on the blog, I’m still alive and QRV on the radio.  The blog had to wait.  Here are some recent activities around K8GU:

  • We moved from our 50’x100′ “city” (WM3O told me it was “suburban” because I couldn’t walk to an Asian grocery) lot to a nice “suburban” (semi-rural) lot of just over an acre in October 2013.
  • In order to work the November DXpeditions and contests, I hastily erected the hexagonal beam on surplus fiberglass poles, as well as the 80-m vertical and a 40-m dipole.  Also, put up several Beverages (yay!!!).  The hex has survived some modest wind gusts, which surprises the heck out of me.  I thought it would have been on the ground by now.
  • Managed to work K9W, T32RC, and T33A on 80m (as well as other bands), which made me happy.  Did not manage to work Z81X (on 80m) through the EU.
  • Put in a nice 19-hr effort in CQ WW CW, SOAB-HP “CLASSIC” (one radio, no spotting), about 1.5M.  It’s nice when WW is before Thanksgiving.
  • Repaired a number TS-930Ses for people.  I think mine will be on the bench soon since the sensitivity appears to be shot.

I’ve never been into making New Years’ resolutions, but some projects are in order for the next few months:

  • More TS-930Ses.  I have one still to fix in my queue, plus mine.
  • Keep refreshing LoTW until the 99 DXCC I presently have confirmed on 80m rolls over so I can apply for 5BDXCC.  I have cards for even more on 80m, but I’d rather do it all on LoTW.
  • Getting some VHF antennas up.
  • Editing my junquebox and ham equipment holdings, mostly parts.  Anybody need some big air inductors and variable capacitors?  6-el 220 beam?
  • Getting on 160 and 30 meters, better antenna for 40.
  • Working FT5ZM on at least one band/mode.
  • Re-installing antenna switching hardware.  Right now I have to run across the basement to move coax.
  • And, a special project that you’ve probably heard about but do not yet realize…details to follow.

So, Happy New Year and I hope your 2014 holds as much interesting and promising to do as mine does!

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Thoughts on QRP

August 22nd, 2013

I recently read an excellent post by W2LJ on non-QRPers’ perceptions of “the frustration of QRP.”  While I’m in 100% agreement with what he writes—essentially to “act loud” when you’re operating QRP—I’m guilty of the very first sin he calls out at the beginning:  advising new hams not to start on HF with [a] QRP [rig].

I stand by this advice.  Here’s why.  The advice is often solicited in the context of saving money by buying a QRP radio (e.g., FT-817, IC-703, KX3, etc) versus a full-power unit (e.g., FT-857, IC-706/IC-7000, KX3+KXPA3, respectively).  Everybody wants to save money, not everyone wants to operate QRP, whether they realize it or not.  It’s a whole heck of a lot easier to crank a 100-watt radio down to 5 watts than it is to crank a 5-watt radio up to 100 watts.  So why does that matter since we’re talking about why people should or shouldn’t start with QRP?  If you operate QRP, look at your log.  You should see a pattern.  Most of your QSOs are on CW or digital and on the “core” HF bands, 40/30/20/17/15 meters.

QRP is not frustrating at all, as long as you operate CW (or digital) into decent antennas on certain bands.  Knowledge and skill indeed trump power.  But, if you are just acquiring knowledge and skill for the first time, a little reserve power doesn’t hurt.  Just my thoughts.

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A Summer Trip to Greenland

August 3rd, 2013

the_office

A professional colleague who is the principal investigator of the Sondrestrom incoherent scatter radar facility announced at a conference that they no longer had a scientific high-rate GPS receiver at the site for making ionospheric measurements.  I enthusiastically volunteered to ship them one that I had on the shelf.  She suggested that instead I should come install it myself and I found some support to do it (the National Science Foundation heavily subsidizes U.S. Greenland and Antarctic scientific travel during their respective summers, making this trip possible).  Therefore unlike my previous trip in the winter, this trip did not involve travel with the most perverse of arrangements flying to Copenhagen only to hop on another plane and fly half-way back to the States.  I set off for my second trip to Greenland, leaving Scotia, NY, early on Monday and returning mid-day on Friday.

On the past trip, conditions were really awful for radio with plenty of visible Aurora.  I didn’t really mind that because the auroras were beautiful, but with only a small chance of NLC/PMC (noctilucent/polar mesospheric cloud) sighting in the summer, I was eager for some good radio conditions to sate my appetite for other nerdy activities.  I set up the radio equipment almost right away the first evening to make sure that everything tuned up and immediately made 10 or so QSOs on 20-meter CW before heading to bed.

Instrument installation is always a hairy business, especially when you can’t just run to a hardware store, let alone going to RadioShack or calling McMaster-Carr.  Sometimes, everything works smoothly; other times it doesn’t.  In any case a flexible attitude (and some good old ham practicality) goes a long way.  Wind gusts of 40-50 mph (18-22 m/s) on top of the hill made for exciting work, but having a couple of helpers made it go smoothly.  Here is a photograph of the installed instrument on its hilltop (the box and green antenna on the right-hand side of the pole, which also held a weather station).

instrument
Work, especially some recalcitrant Windows 7 issues (At one point, I was running Windows 7 in a VirtualBox virtual machine on a Linux machine and logging into the Linux machine from a Mac!), kept me pretty busy on Tuesday and Wednesday and I only managed a few minutes of operating on each of those days.  But, by Thursday, my schedule broke loose a little and I was able to operate for a few solid hours in the afternoon and evening.  I had no idea that Greenland would be so popular on 30 meters!  Wow.  That’s definitely the most intense pileup I’ve ever experienced.  Thanks for being patient.

There was some about S3 hash on 20 and 30 meters that the K3’s NR function would take care of but the NB function wouldn’t.  NR is not good for running pileups, so I often had to get the caller isolated to use NR.  On the receiving end, there was a lot of fast QSB, with a period of a few seconds (this is consistent with magnetospheric and plasmaspheric waves that impinge upon the auroral and subauroral regions.)  In any case, callers were up and down, often in the span of a call.  You all on the other end may or may not have observed the same from me.

Per usual, the setup was an Elecraft K3 and the GU Special vertical with 2x 1/4-wavelength radials for each of 20 and 15 meters.  Everything else was tuned by adjusting the length of the radiating section.  This is a substantial improvement in performance-to-size ratio over the previous station I carried in January 2012, which was a Yaesu FT-840, DK9SQ 10-meter telescoping pole, and a variety of wire antennas.  Below is a photograph of the GU Special deployed (it’s in the center, unceremoniously ty-wrapped to a wooden sign post sticking out of a barrel).  The diesel Toyota HiLux pickups are the most popular vehicle in town.  We gave a visiting graduate student lessons in driving a manual transmission.  Great vehicle to teach/learn on with lots of torque and low gearing!

gu_special_sonde

Although I was unable to connect with them, we did drive past the OX2A/XP1AB site on Black Ridge that overlooks downtown Kangerlussuaq:

ox2a_xp1ab
Thanks for the QSOs.  The log has been uploaded to LoTW this morning and QSL cards are ordered.  I never ordered cards after the last trip, so it will be a shared card with a photograph of the aurora.

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RSGB IOTA Contest expedition to NA-140

August 3rd, 2013

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I forgot my camera at home and my mobile phone battery died so there are no photographs of this adventure…

I first experienced the passion of those pursuing RSGB’s Islands on the Air (IOTA) programm(e) when I was active from Adak (Andreanof Islands, NA-039) in August/September 2012.  Matt, KB9UWU, and I made some tentative plans to do the 2013 RSGB IOTA Contest from NA-139 (Maryland State East, Assateague), returning to the site where he and W3CF had done the same contest over a decade prior.  During the planning stage, I cast about for the nearest IOTA groups to activate.  For the DC area, the easiest groups are surrounding the Delmarva Penninsula, NA-083 (Virgina State), NA-139 (Maryland State East) and NA-140 (Maryland State West).  We did not execute the plan to go to NA-139 and I had really given up on the idea of doing anything for the IOTA contest…

That’s when work interviened.  I scheduled a trip to Greenland (story about this to follow in a future posting) leaving late on Sunday of the IOTA contest weekend.  My wife had a cousin with a baby shower in Ohio on Saturday…so, we did the logical thing…packed her and our son off to Ohio on a Saturday morning flight.  After dropping them off at the airport, I headed to the Eastern Shore for some IOTA action.

The principal mission for this trip would be to understand the difficulties in activating NA-140 and to make it widely available to the IOTA community because it is apparently rather rare (25% claimed, versus 19% claimed for Adak).

The station setup was simple and typical—an Elecraft K3 and an updated version of the GU Special.  The GU Special had just returned Tuesday from KL2HD’s KL7NWR expedition to NA-064 back in June (he had left it on the research ship until it returned to port, so technically, it’s probably visited some other rare IOTAs, too).

In order to avoid discharging the car’s battery, a mistake that could leave me stranded far from home, I lugged along a few SLA batteries to power everything.  I selected a couple of candidate sites using aerial imagery and ended up using my preferred site, which was very accessible to saltwater and the road, making it trivial to setup the radio in the car and
the antenna on the beach.  I now understand why NA-083 and NA-139 have much more activity—they’re close to civilization!  Nevermind, I love the middle of nowhere.  So, it was fun.

I configured the antenna for 20 meters and launched a few CQs on CW.  It took a while to get a run established, but after that the pileup was pretty much non-stop for about 3 hours.  I even worked some JAs, which was pleasing considering that NA-140 is very rare there and I was not QRV during the peak hours for JA.

Unfortunately, I hadn’t rigorously tested the batteries beforehand (except for one) and only one (the one I tested, of course) of the five performed well.  One performed acceptably and was relegated to running the inverter for the laptop once the battery warning came on.  Even the “good” battery sagged under load at 100w transmitter power.  So, I cranked the K3 down to 50w and let it rip.  That was enough to produce a commanding signal in Europe, with RBN Skimmers showing my signal peaking at 47 dB SNR with many hits in the 30s of dB.  As Matt said when we talked after I returned home, “I have trouble getting those kind of numbers with a small beam and the legal limit!”  Verticals on saltwater rule.  End of story.  Hearing was a different issue as there was some line noise and the occasional passing boat, who provided more QRM in the audio range than the RF range.

My pileup thinned out a little bit around 2020 UT and I was exhausted.  Evan didn’t sleep well the night before and that didn’t help anybody else sleep, either.  Plus, it was hot, even with the nice breeze and pleasant temperatures.  If all of that wasn’t enough, the battery in my mobile phone had discharged, the battery in the laptop was nearly dead and both the K3 and the inverter began
throwing low-voltage alarms.  It was time to pack up.  Fortunately, the GU Special deploys and stows in 15-20 minutes, so it wasn’t bad.

I ended the three-hour window with 215 QSOs and 11 (!!! that’s what you get for CQing the whole time) island multipliers, all on 20 meters.  I’ll take it!  Thanks for the QSOs.  I just ordered cards today and they should be printed and ready to send by mid-August.

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K2BSA

July 19th, 2013

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Worked my good friend and professional colleague Nathaniel, W2NAF, who is a radio instructor at the 2013 National Jamboree. Fast QSL with a special postmark. Ham radio continues to be cool.

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Review: Array of Light (3rd Edition)

July 9th, 2013

My friend Matt, KB9UWU, eggs me on to buy things.  Sometimes I listen.  Sometimes I don’t.  But, eventually he wins me over and I’m usually happy with the purchase (e.g., K3 and Hex beam, although I built the Hex from scratch, which reminds me that I owe the blog a discussion of that).  I like to think that I let Matt be the early adopter and then pick and choose based on his experience.  He convinced me to buy a copy of N6BT’s book Array of Light.  Here’s my review.

If there’s anybody that knows antennas in the amateur community, it’s Tom Schiller, N6BT, the founder of Force12 and now owner of N6BT Next Generation Antennas.  He’s also a member of the very successful Team Vertical contest team, who have revolutionized DXpedition and contest expedition antenna systems by replacing trapped tri-band Yagis like the TH-3jr(s), TA-33jr, and A3S, with arrays of verticals located at the water line.  Schiller’s work has been nothing short of revolutionary so I had high hopes for the book.

My copy, like every other copy, is signed by the author.  It’s a good-quality laser print and has the same spiral binding as the Elecraft manuals.  The book is a loosely-edited collection of articles and clippings that read pretty well in series.  But, it’s bear to skim or go back to find specific things unless you’ve read the whole thing cover-to-cover a couple of times.  But, that’s pretty easy to do because Tom is a good storyteller.  My only other complaint is that there are a couple of places where I think Tom has drunk his own Kool-Aid regarding the efficiency of his antennas, especially “linear loading.”  This is a topic that I need to revisit with a pencil and paper study at some point because there is a lot of misinformation floating around about traps, linear loading, and “multi-monoband” antennas.  It’s not clear to me that anyone has sat down and really examined this in a methodical way.  It was disappointing that he quoted numbers like “greater than 99% efficiency” without going into more detail about the efficiency of a full-size antenna versus the linear-loaded one, etc.  Of course, this is difficult, but it’s something that always makes me a bit skeptical.

Array of Light is worth the price of admission for a couple of reasons—the first is the stories and the second is the antenna designs.  I’m a big proponent of not reinventing the wheel on most of my homebrew projects and this book is sure to provide some proven designs to work with.  Especially if you want a good discussion of practical antennas for DXpeditioning and contesting I think it’s a real winner.

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Do you see what I see?

July 7th, 2013

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  1. Crystal oscillator for 98.5 MHz.  Check.
  2. TUF-1 and TUF-3 mixers.  Check.
  3. SMT protoboard.  Check.
  4. MMIC amplifiers.  Check.
  5. Larcan TV exciter amp.  Check.

Do you see what I see?  Yes, a 222-MHz transverter is on the horizon.

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Dayton 2013 Recap

May 20th, 2013

dayton_big_dish

Some good planning on Sarah’s part yielded a bridal shower for her sister scheduled on the same weekend as the Hamvention.  Huge win.

  1. Speaking of huge wins, there was no sewer back up this year.
  2. Like the last time I attended in 2011, I’m pleased to see more younger (than me) hams in attendance.  A high-ranking ARRL official noted to me the “energy and enthusiasm” present in this generation of young hams that was not present 15 years ago (this year marks my 20th year as a ham, but I didn’t mention that).  Attendance was still thin compared to my first visit in the mid 1990s.
  3. Deals.  I stimulated the economy by purchasing a small CDE rotor for my VHF activities, an HP server power supply for a future solid state amplifier project (>55 amps at 50 volts), a couple of 900-MHz antennas, and some miscellaneous small parts.  I sold some junk to partially cover that expense.
  4. People.  Ran into a lot of old friends and made some new ones.  This is really why I go to Dayton, well, that and the junk.  K8MFO tells me there are Bureau cards coming.  W8AV has 930s for me to work on.  W2NAF had people for me to meet.  AD8P was able to win himself a pizza from an unnamed W5 in the “SB-200 challenge” of correctly differentiating an SB-200 from an SB-220 at a distance of 20 feet—a tribute to the W5’s failure to distinguish the two until after the sale last year.
  5. W2NAF has written an article about our trip to Adak (NA-039) that was published in the June 2013 issue of CQ.  It has a lot more background detail than what I wrote on the blog.  Check it out.  I picked up a copy of that and the May 2013 issue which has the 2012 CQ WW CW results in it.
  6. Products.  I just don’t care that much about new products.  The Ten-Tec Rebel that several people have already discussed is a cool idea.  I know that Ten-Tec took some flak for not opening up the Orion SDR core when they produced it.  But, let’s be realistic, people.  Hams would have bricked those suckers in a heartbeat.  A sandbox “open source” radio is a step in the right direction, but I question what a ham can really customize that matters without screwing it up.  Maybe I’m just not visionary enough.  Almost 10 years ago now, I interned in the R&D lab at a large consumer appliance manufacturer as an undergraduate my supervisor was always saying, “How can we make this attractive to the [hardware] hackers?”
  7. Guns.  The Hamvention web site was very specific that the Trotwood Police Department would be actively enforcing Hara Arena as a non-gun zone.  Seriously?  It’s a ham radio convention.  Bill Goodman is there at least once a month the rest of the year.  Do hams bring their go-kits to gun shows?  They must.  Inquiring minds want to know…
  8. Suites.  I did not do the contester suite thing.  Was thinking of going on Friday night but fell asleep in my in-laws’ living room.  This is a recurring problem when I visit so no one bothered to awaken me.

Was the trip worthwhile?  I think so.

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