An operation on the beach as an expedition is always a great chance to learn new stuff. This year we learned that fiberglass mast is pretty flimsy and aluminum is much stronger – not a revelation.
After some extensive modeling by K2AV, we settled on using ladder line fed doublets that were 56 feet(17.2m) in total length, 28 ft per side. The models show that length to have useful lobes on 15m and 20m, without loosing much over a regular 40m dipole. We ran the ladder line to just behind the radio’s into 4:1 baluns, and used the radio internal tuners for matching. [I'd have preferred outboard tuners.]
We didn’t get good enough propagation on 15m to decide if they were making a difference, but two of these antennas at right angles, with their apex at 40 feet, seemed to work very well on 40m and 20m. On 20m, there was a worthwhile difference between the two antennas, several s-units in many cases. The signal level difference on 40m was more subtle. The pattern on 40m at only 40 ft high is mostly omnidirectional anyway.
Lacking an appropriate vehicle is somewhat of a problem for this sort adventure. The island has only sand trails, no real roads, so 4WD is recommended. N3ND volunteered the use of his AWD Toyota Highlander this year. We were able to get everything packed inside or laid on top, but it was a snug fit.
2010 was great WX wise. We had blue skys and a steady cooling sea breeze for the duration of our stay on CALO. Saturday afternoon was particularly pleasant, with low humidity and moderate temperatures making the afternoon very comfortable – the first time we have enjoyed such good WX for an expedition.
Operating was a lot more fun in 2010 compared to the previous three years due to slightly improved propagation. Friday evening booked a few pages worth of QSO’s to both the US and Europe on 20m and 40m. When the RSGB IOTA contest began on Saturday morning, we enjoyed a decent 20m opening to EU on both CW and SSB, and even a few JA’s getting into the log then. Propagation to Europe faded during the midday, but began picking up towards mid afternoon. 15m never really opened, and 10m was completely unproductive. Its been a long term goal to make Q’s on 6m from CALO, but the e-skip never sees to coincide with our expeditions. This year was no different – nothing heard on 6m.
Pulling the graveyard shift wasn’t very productive for QSO rates, but there were some great Pacific Q’s to gather there. VK7, ZL1, E51, WH6, NH2 all made it into the log then. That was fun, even if it caused symptoms of sleep deprivation later!
The mast gear seemed to be in good shape, with the exception of one folded stick of fiberglass. Going to 40ft is more difficult than going to 30ft, but is not impossible with at least two people. Lifting 30ft is possible for one person with proper guying, but the mast is too heavy for one small person to lift to 40ft. Possibly with a gin pole – but the additional rigging needed for the gin pole is time consuming, and extra gear required is not available at this time.
The Good: Great WX. Good radio conditions. We blew away all our past mileposts for the bottom of a sunspot cycle, new high of 1196 qsos and 1.4m points. K2Av was great opening 4om CW, and N3ND and N4YDU both had great runs at various times during the day. Homebrew compound baluns didn’t melt. A few day before leaving for the island, noticed that RSGB had posted the list of 2009 Trophy winners – and N4A nabbed the plaque for North American expeditions again. SWEEEET!
The Bad: W0UCE missed due to a family illness. Pesky intermittent noise, we think from a UPS. Just hate using, for contest logging, N1MM.
The 160 Inverted-L is about 160 feet of wire. To get a good match there is a series capacitor in line with the wire. The bandwidth for any useful value of capacitance is about 40kc. The object is to use a set of relays to switch in or out additional capacitors. That will allow the antenna to be tunable across most of the band – from 1800kc to 1930kc. There is also a 1.5:1 unun at the feed point, followed by a coax cable choke. This lowers the SWR to a very nice 1.1:1 over the useful range. The rig is very happy at resonance, and a good match will be a dial click away.
Currently the capacitance in the system gives a nice 1:1 SWR at 1825kc. Using the autotuners, either radio [K2, FT-920] can work from 1800 to 1875. The goal is to be able to turn off the tuners and feed the antenna directly. Maybe I’ll pick up a few extra QSO’s with a good match on the antenna end of the feedline.
After several other projects using relays and the 3kv Panasonic capacitors for the band pass filters, enough extra parts are in the parts bin to make it happen. So, why wait?
A handy nearby line previously shot into a nearby biological antenna support provides an opportunity for expansion. The line seems well placed to add an INV-L element for 80m. One additional relay for switching bands. Judicious choices for the capacitance values may allow the sharing the capacitor banks for either antenna. Being able to cover the CW segments is most important, so the minimum value used would ideally resonate each wire near the bottom of either band. Hmmmmm. Time to pull the 80m wire up and start tinkering.
Getting home from vacation a couple of weeks back, a huge branch was found in the rear area of the antenna farm. One ginormous limb had fallen from one of the white oaks holding the north-south 40 meter dipole. It was on the opposite side from that antenna, but must have crossed paths with the 80 meter folded dipole on the way down. The bad news is that the 80m antenna was on the ground, as well as six or eight radials from the nearby inverted L for 160m. The good news was that only the line holding the antenna itself had failed, and not the line over the branch, and the nearby 40m vee was not effected.
On most of these hard to hit branches, the approach that usually works best is to use two lines for the center load-bearing supports. Once a pilot line is shot over a branch, a heavy line is run up and over to make a loop. At the joint in the heavy loop line, a pulley is attached. The actual antenna support line is then run through the “pulley”. Haul the pulley up to the desired height, paying out antenna support line as it goes up.
Note: The “pulley” is usually just a simple welded steel ring, attached to the heavy loop with a swivel. Real pulleys often bind – never a problem with the simple steel rings, although the steel ring may cause the line to break more often. The swivel is to offset some of the twist a line can take on when being hauled up 50 or 60 feet.
Using that method, the heavy line over the branch can usually be pulled up and left alone, reducing the amount of line “sawing” that is caused by raising and lowering a hard-to-tune antenna. More importantly, the line over the branch breaks less frequently. Easier to pull the ring down and send up another support line than to shoot a new pilot line.
So – One dead folded dipole. Worse, its always been my favorite antenna for 80 meters. It has a broad bandwidth, and seems to do a great job in the domestic contests.
Making lemonade out of lemons, it was a great time to do long delayed maintenance. The line over the branch was at least three years old, maybe four. Worse, its probably too lightweight for the spot – a large branch at about 70 feet. It was a hard shot to hit, so the heaviest line available. about 10mm, was pulled into place as a replacement line for the pulley support. The antenna pull line was also replaced, using 6mm line.
With the new support lines ready, one other minor issue was repaired. The antenna was built directly from the cookbook dimensions, from an article in the antenna book chapter on portable antennas. (Reproduced with permission in the Cary Amateur Radio Club newsletter, the Feedline). The tuning option used was the open stub of twin lead, since the twin lead was here back in 2002, but no suitable capacitors. Since then the parts bin has been augmented with suitable panasonic capacitors.
The twin lead stub functioned properly, and was trimmed only slightly from the cookbook dimension of 37′4″[11.28m] . The “third leg” was always a bit of an additional problem to deployment, as it needs to be stretched away from the feed line rather than coiled as might be possible with a coax stub. Plus the extra weight.
The stub was removed, and the junction was repaired physically. 240pf of 3kv capacitors were pulled from the parts bin and used to replace the stub for impedance matching. The cookbook called for 289pf, but I took the time to experiment. The 240pf value was arbitrary, but it paid off. the original antenna had a 2:1 SWR bandwidth from 3550 to about 3920, with the sweet spot of 1:1 at 3730. The modified version using 240pf for matching lowered the 1:1 point to 3675, and the 2:1 bandwidth extends from 3500 to about 3860. The autotuner in the FT-920 has no problem providing a good match across the entire 80m/75m allocation. With 100w, my 80m results have always been competitive.
When re-installed, it was also possible to get the apex a bit higher than before. Nice. Hopefully it will survive a few more seasons before needing additional work.
Had fun again for Field Day with N4YDU. Always do. Even though it was miserably hot and humid this year. Operated this year under the NC Contesters call NR3X.
We had a crew of ‘ringers’ on 40m CW. W0UCE, N3ND, and K2AV ran up a nice QSO count on 40Cw. Other operators were AA4XX, K4CZ, N4GU, N4YDU, and W4KAZ. With the extra operators on hand we operated class 3A. AA4XX and K4CZ were only available for the first few hours, so in the end we wound up with about seven or eight hours of idle time on two of the stations. Gotta sleep sometimes.
With one station dedicated to 40m CW, the other bands/modes were spread between the other two stations. Station one was 40m ssb plus 10m/15m. The second station handled 80m CW and 20m CW, plus 20m SSB.
A late afternoon thunder storm chased me out of the 20m CW shack for just over an hour at about 4:00pm local on 06/26. To hell with that! I like operating, but not enough to die for. Also had a couple of computer problems early on with the setup for the 20 CW station. Piddled away some time resolving those. (Problems: N1MM has a faux “Elecraft K2″ radio option that does not work [MUST use "Kenwood"], and when the laptop went idle its power saver caused N1MM to hang up when using its function key macros [solution re-boot laptop. Better Solution: Use writeLog])
The 80m/20m CW station had dipoles for each band, fed with ladder line. The 40m ssb/10m/15m station used a G5RV sized doublet, also fed with ladder line. At the 40m CW pit, two crossed 40m dipoles were played.
Final tally was 2746 total QSO’s for a score of 9600+ points. Close enough to 10K to taste it. Close to 3K QSO’s, but not quite close enough.
(This post to be amended as more links turn up, de w4kaz, last update 2010-06-09)
Well, sure, Dayton 2010 was probably very much like 2009, or 1995, or 1970. But its more fun to go than to stay home.
But congratulations to my friend Nathan, N4YDU. This year Nate placed 6th the in the annual pile-up competition sponsored by the Kansas City DX Club. (If you want to see what the competition is like, the club has sample audio files posted, as well as a custom logging program provided by VE3NEA.
For those of us unable to experience the 2010 Dayton Hamvention in corpus, here is a round up of the easy to find “stuff”. Send me a link and I’ll add it to the list if it seems suitable.
More randomly chosen Youtube video, here, here, here, here
And if you want a professionally done video, perfect for a club meeting program, for $15USD you can get the 2009 mooo-veee from central NC local Gary, KN4AQ. [I'm not affiliated with Gary, nor any pecuniary interest in ARVN. Gary has been doing a great service by documenting recent amateur activities. I've seen his work, so $15 is a bargain with the forum material included.] [2010 release??? see KN4AQ's comment.]
N4YDU was on the sidelines/out-of-action for the weekend, so I took NR3X out for a spin in the WPX. So for those who would be wondering why NR3X was suddenly a lid, well, there it is. Apologies to all who expected NR3X to be piloted by a good CW op.
Original plans to put in a more serious effort evaporated, so it became a great chance to play SO2R using spots. Logged about 8 hours total Butt-In-Chair time over the entire contest. The shack has a new scavenged computer, so it needed a shakedown anyway. The one item not ready was the Winkeyer2, which showed up in the mailbox only a few hours before ’showtime’ on Friday. Despite an initial urge to slap the winkeyer together, it remained(s) un-built. Lacking an additional USB to serial interface, it could not have been used anyway. Soon!
The ‘new’ ShackBox CPU has a clean win XP install. On a tip found on the Writelog support forum, the “PortTalk” program was used to circumvent the parallel port issue, but the winkeyer will render that workaround moot. For handling packet cluster and skimmer merges, the wintelnetx program by K1TTT was installed. Wintelnetx is relatively easy to configure after the “route” settings are understood, and K1TTT has sample ini files included which make it easy to get started. This tutorial for TR is helpful.
With wintelnetx configured to pull spots from the normal spot network and from N4ZR’s skimmer node, the band maps are populated in a very short time. Very interesting.
With the weekend shaping up as an hour or two here and there, poking spots seemed like a good idea. Friday night turned into a bust, with a local T-storm showing up overhead around 0100Z. Bail! Saturday morning conditions were poor. Normally loud EU stations were not, and few were hearing the low-power-low-antennas from the KazShack very well, so it became mostly a click and shoot on US stations and the occasional loud DX. A few 15m Q’s added to the mix, but not generally good propagation. 20m opened to EU around 2000z, with 40m picking up just a bit later. Seemed more like mid-summer IOTA propagation.
Conditions Sunday seemed a bit improved, but less time spent on the air, missing the late afternoon opening entirely. Closed out the contest trying to run on 40m, which produced a few interesting Q’s.
Things to Fix: Fix LID operator! Need to decide how best to correct the SO2R audio switching. Simply reversing the L/R phone audio might be easiest fix, but probably would best be served by figuring out exactly what was haywired originally
The GOOD: SO2R set up performs flawlessly. New ShackBox CPU also integrated without problems. Skimmer spots are more useful than ordinary packet spots, would be ideal with a local node[great club project idea]. Good results on 40m, conditions seemed good there and even had a good mix of EU stations call into my run in the last hour.
The BAD: Propagation seems to have returned to ‘no sunspot’ mode, and summertime conditions have already taken hold.
The UGLY: Busted calls. Busted exchanges. Busted LID operator.
Noticed on Saturday last week that the log check reports for the 2009 ARRL 160m contest had been posted on the ARRL website. How I found them, I’m not sure. The ARRL site has been well shuffled. In my life as a DP professional, it was important to stress the significance such sweeping change would have to the hapless victims – i.e., the poor folks who actually used the program interfaces to get their jobs done.
Its like this – the hapless victims(in this example ME) had a working knowledge of “how it works”. That knowledge was reinforced by 0 to 20(eleven) years of hands on habitual training. Sometimes that is good, sometimes not good. Tossing these years of “habit” is often more or less equivalent to firing the entire staff and starting with fresh high school grads. Sometimes that sort of drastic change was required to achieve the goals. More often it was just done on the whimsy of the dork making the decisions. So – whimsy or requirement? But I digress into grumpy Old Fart-ville….
Yet I am smiling. The LCR, once found, is for me one of the best things about the ARRL contests. It is a blow by blow breakdown of what was screwed up. In this case the 2009 ARRL 160m LCR is better news than most. It’s the best CW LCR I have had – ever. On 201 QSO’s I busted only 2 calls, and had one exchange busted. O’course, it was only 200 Q’s total, but improvement is always good.
Operating for only about four hours, about half of the QSO’s were from runs, and the rest from S&P. The rate was low by Bigg Gunn standards, but about normal for the low power 160m KazShack. This low error rate even beat out a lot of my SSB LCR’s. It may in fact be the best LCR for any of my contests, either mode. SWEEEET!
Now, I just need to get the Sweepstakes log(and every other log) to be as good as this ARRL 160m log. Sweepstakes was terrible. In 2008 most of the errors were on the exchanges. 2009 CW Sweeps was a step backwards, with more callsign busts.
Sure wish I knew what was different – it would be better to have more logs like the 160m ‘test. The ultimate goal is a 500 QSO CW contest log with zero errors.
When pigs fly…..for now I would be happy with a consistently low error rate.