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The operator himself. First licensed at age 13 as WN0WEZ (1968), then WA0WEZ (1969), K7TI (1977), K7TI/VS6 (1982), T32AG (1983), WH6B (1983), AH6SG (2005), and recently MM/AH6SG (2006) (Thanks to Ian, GM4YSN). This recent phase of activity has begun a renewed interest, after a long QRT of over 20 years.
Main rig is an FT-920, with all the InRad modification boards. They really make all the difference in an otherwise poor receiver. I also recently added an IF output so as to run an SDR, which now makes for the best of both worlds. The amplifier is a homebrew version of the Motorola EB104 design, which runs 600W PEP using 4 MRF-150's. For an example of this, see the website of K0GKD, and also the reviews for Communications Concepts kits on eHam. (There are those that claim the use of diplexer type output filters is advantageous, but that does not seem to be the case. Simple filter types do just fine.) I am pleased at how cool the amp runs. Given my power system (see below), the efficiency of this amp is appreciated. As far as I am concerned, the tube is dead, unless you live in the far north and need a morale boost on a cold winter night.
I have recently (mid 2008) raised 23m of Rohn 45 tower. I managed to scrounge or salvage most of everything, but at a cost of large amounts of labor. That's OK, as I have much more time than money, and I much prefer to keep old things alive, rather than buying new. (There is plenty of stuff already on the planet!) All aspects of the tower are done by hand, as there are no cement trucks to fill the holes, or cranes to do the lifting. Even the holes were dug by hand, although really it is more chipping out rock, than digging, in our shallow volcanic mountainside. On top I have a 2el 40M yagi, based on the XM-240 but completely redesigned with longer trussed elements and high Q air wound coils. Below is a wide spaced 4 el 20m yagi on a 12M boom, built from the remains of some storm crashed KLM's from the 80's. Both antennas were modelled using the MMANA antenna software by JE3HHT. There is also a Cushcraft X9 at 11m which I am using for stacking experiments. It is fixed on stateside.
On the subject of software, I use Ubuntu Linux on my Gateway ML6872 laptop. It works very well for my needs. For Ham functions, I use: fldigi, xlog, MMSSTV, MMANA-GAL, xdx, Azmap, and sometimes linrad. A number of other ham related programs are made for Linux, and many others work through the Wine software. I am pleased to be out of the MS domain and taking advantage of Open Source software. It is a big step forward and very much closer to the original ham ethic of tinkering and experimenting.
The modeling software I use, MMANA-GAL is a very capable freeware program that is also a great way to learn about how antennas work. I have written a short tutorial on how to get started with the opening example models and use of the optimization engine in this program. It assumes you have some basic familiarity with antennas already. Most amateurs seem to have focused on the EZNEC software, but I highly recommend taking a look at MMANA-GAL as it has more sophisticated tools for design purposes.
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On 80M I am have an almost full sized vertical ground plane, feed point at 10m high, with 4 elevated radials. It is lashed to the side of a topped Norfolk Pine tree. They are unfazed by such treatment, and grow back vigorously. Hey, no rust! On 160m I shunt load the main tower, with about 35 short radials for a ground. Our soils tend to be rather wet, so this seems to be sufficient to get out reasonably well.
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On a second crank up tower I have a 4el 15m yagi at 17m high. The view on the right shows the antenna's outlook on the world to the south. Long path signals are quite strong as a result of the water shot. We don't work well to the north or northwest though, as the 3,300m bulk of Haleakala rises steeply behind.
Below are some views of the QTH of NH7O, also known as Kalepa Farm. It is located on the south side of the island of Maui, just across the channel from the Big Island. The area is very remote and isolated, and there is no grid energy available. All the electricity used on the farm is generated from alternative sources. We use a 2 KW windmill, which in our zone of strong trade winds, does very well. We also use solar panels for calm times, and there is a Pelton wheel which can generate power from the pressure in our water line.
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In my work with alternative energy, I researched a bit into maintaining the health of lead-acid batteries.
You can learn about my circuit and testing on the Desulfator pages, hosted by a friend..
If you would like to send an email, I'm nh7o (at sign) starband dot net.