nw2s

I wasn’t extremely happy with the PC satellite control software out there, so I decided to do something about it. The process was quite a learning experience – it’s my first true multi-threaded GUI app (as opposed to the web apps I’m usually building) and I learned a lot about basic satellite prediction.

It’s based on bits and pieces of other open-source software out there, but
architected using a more modular approach with decoupling done through a series of event handlers set up as a bi-directional message bus. I release the code on Google Code and wrote an article for the AMSAT Journal (122.55 KB).

I
know that lots of people have made successful QSOs using an array of
HT’s, mobile units, and any number of home made antennas. I started
similarly small, but had a couple of different design goals for
satellite communications.

First, I am somewhat limited by my
pool of equipment – I don’t have old radios around or an HT that can be
brought into service. I want to get as much use of what I have, but I
also will need to make investments as they make sense.

Second, I
want to be able to work satellites from my current base which includes
a 75′ feedline to the antennas on my roof. While mobile/portable
operation is a goal, I’d like to start with more and pare down for
portable work rather than the other direction.

Lastly, and
perhaps most importantly, I want to engineer a solution that will
produce reliable, repeatable results. As exciting as the first few
contacts are, if I am to use satellites as a reliable means of DX work,
I’d like to remove as much of the luck from the equation as possible.

Don’t
take my example as any sort of assertion that I think this is the best
way, or even how anyone else should follow my lead! I just wanted to
share what I got to work and the results.

The antenna is a
Cushcraft 2m/440cm 3 element yagi mounted about 50′ above ground and
15′ above the roof of my apartment. It is mounted to a simple
light-duty TV rotator. The bands have different feed points and
elements but share a boom.

Each antenna is connected to an SSB
preamp through 3 feet of 9913. The 2m is using 75′ of RG-8X and the
70cm feedline is 75′ of RG-213. The 2m antenna is driven by an IC-V8000
and the 70cm with the IC-7000.

I am currently limited by the
antenna in a couple of ways. First is that I have no elevation control
and the antenna to mast mount is fixed at 90 degrees. This means that I
can work satellites as low as 7 degrees, but seem to lose them around
20 degrees elevation. Unfortunately, this also means that I am unable
to take advantage of higher elevation passes which would have a lower
path loss. I had also intended to run full-duplex mode and used the two
different transceivers. Unfortunately, since the two bands share a
boom, they interact heavily and the 2m transmission completely
overloads the front-end of the IC-7000.

In keeping with my goals
of making reliable communications, I’m going to make a few more
attempts making only a couple of tweaks to the setup above. Ultimately,
though, I will move to some antennas like the Gulf Alpha 70CM-8ELSat and 2M-5ELSat
at about a 20 degree elevation on an 8′ cross boom. I will replace the
6m beam for now since it will most likely be a while before that band
sees any propagation more than the hour or so a month that I catch.

Many thanks to the AMSAT-BB list, Gary WA2AQH, and the SatComm Net hosted by the MBARC . If you’re in the area and want to join in, it’s every other Thursday at 20h00 on the KC2DAA repeater (144.225 pl 100.0)

I’ve been having a lot of fun working HF and a few local repeaters, so I wanted to share my experiences as a newcomer to the hobby who is one
of the dreaded new No-code Extras.

Starting off, I had a lot of luck just tuning around the New York City area 2 repeaters. There were a lot of friendly folks on the air, and it got me in the habit of good QSO procedure. When I moved from the mobile antenna mounted to the balcony railing to a rotated yagi on the roof,
my goal was to reach repeaters as far away as possible. I was particularly interested in reaching repeaters closer to the catskills…

The most consistent repeater I was able to reach is the KC2DAA repeater on Mount Beacon. This repeater hosts the Hudson Valley net as well as some activities of the MBARC such as a semi-weekly Satcom net for discussion of area satellite work.

It took about a month to get word of my General/Extra upgrade. At that point I was diliberating a solution for multiband HF access. Quite a few people extolled the virtues of the G5RV and the price was right. It turned out that I didn’t have as much room for a wire antenna as I thought. I did manage to use the G5RV for a few 6m and 20m contacts at a friend’s house in the Catskills.

After ruling out any sort of wire antenna, I turned to the vertical. At the time, the only real benefit that I realized is that a vertical is self supporting. I planned to mount the antenna on the roof of the apartment which is about 40 feet above ground and contains very little metal mass.

I ruled out the radial-less half-wave designs primarily because of their comprimised design, and mixed results in the review pages of eham.net. Of the multiband 1/4 wave designs I settled on the Butternut HF9V with the tuned radial kit. Installation and tuning whent great, and I am constantly surprised about how well it performs.

In the end, another huge benefit of the 1/4 wave vertical design is the low radiation angle which makes it great for DX work. In fact, it’s so good, my country list is longer than my state list!

States Worked

• Alabama
• Massachusetts
• Mississippi
• Ohio
• South Carolina

Countries Worked

• Europe
• Spain
• France
• Hungary
• Italy
• Norway
• Czech Republic
• Slovak Republic
• Belgium
• Russia
• North America
• Cuba
• Honduras
• Canada
• USA
• Mexico
• Trinidad & Tobago
• South America
• Columbia
• Argentina
• Venezuela

Since I’m only running 100 watts, I’m limited to conditions which haven’t been great. That being the case, I’ve been able to make at least one 5×9 contact with any given attempt.