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The fact that there's a space station orbiting above the globe right now has become somewhat passe in pop culture. Not many people are truly wowed at the news of it. Within seconds, a few clicks of a mouse will take you to hundreds of pictures and videos of the International Space Station; but did you know you can see the space station yourself? No binoculars or telescopes needed! I figured I would write up a HOWTO for the uninitiated. It isn't hard, it just takes a little know how.
For starters, you need to know a few terms used when talking about satellites (the ISS is a satellite of the planet Earth).
Azimuth
The first term when dealing with satellites is azimuth. Azimuth is a technical term that means the same thing as heading, bearing or direction. Most people are comfortable with the cardinal directions North, South, East and West. The cardinal directions are fine for general directions, but to know exactly where something is we need to be more specific. When dealing with an azimuth, a number of degrees is stated. 0° is North, 90° is East, 180° is South, 270° is West, and on around to North again. Kinda get the picture? It's a full circle divided into 360 degrees. (Also note, there's technically no such thing as 360° when dealing with Azimuth, because 360° would be the same as North, but that's already 0°.)
Altitude
It's not entirely what you think. Sure altitude means height, but we're not talking in feet or meters here. Remember, we're dealing with observational angles here, so knowing how high something is is of little consequence to us. Altitude in astronomy means "angle above the horizon". Altitude is expressed in degrees, just like azimuth. 0° is at the horizon, 90° is straight up. 45°, you guessed it, is right in the middle.
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tags: iss space astronomy satellite howto
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A local ham recently asked me the best way to talk on ham radio satellites using what he already has on hand. It doesn't take much, although some more specialized equipment does make it much easier, but the point is - you don't need much beyond what you may already own if you have a basic VHF/UHF station. The following is my email to him:
Which birds to target and how to track them
"The best satellites to start with are AO-27, AO-Echo and SaudiSat-1C. (Satellites go by different names depending on where you're getting your info.)
I usually direct people to Heavens-Above to get the latest pass information. The exact time and angle of each pass varies from day to day, so you either need tracking software or a website to tell you when the next pass is over your location.
With Heavens Above, you need to enter your longitude and latitude, so it can figure out the information for you.
I've put in the longitude and latitude in for my QTH here in Longview on this link:
http://www.heavens-above.com/main.aspx?Lat=32.5560&Lng=-94.7474&Alt=365&Loc=N5DUX&TZ=CST
(change the location by editing the link or click on the link under Configuration at the top of the page)
When you go to the website, you'll be shown a lot of different links. For our purposes, we're interested in "Radio Amateur Satellites". Click on that link.
Now you'll be presented a table of all the various satellites that Heavens Above is tracking. I usually find the satellites I'm interested in working, then look over at the "maximum elevation" - this is how high in the sky the "bird" will get. Generally the higher the pass, the better chance of hitting the satellite you'll have. If all you're using is a vertical, 45-degree passes will give you a good shot. But anything greater than 30-degrees should be doable.
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tags: satellite ham radio intro howto
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Since I got my Arrow Antenna, I've been trying to contact all 50 states by satellite (aka Worked All States). I know a few states are going to be tough (if they're even possible). I know Alaska and Hawaii will probably have to be a scheduled contact. Since the pass that will allow us to contact each other will be very low on the horizon. I have been getting about 2 passes a day from the satellite AO-27, one usually to the east then the second passing more to the west. I've been steadily adding states as I hear them. I'm also making contacts via Echo (AO-51) which is very busy on it's nightly passes.
If it weren't for the listing on Heavens Above, I'd prob be lost as to when to listen for a satellite. For those stations that have sent me a QSL card, I will send out a batch as soon as my new ones arrive. The map above is a listing of those states which I've contacted (yellow) and those that I've received a QSL card from (green). |
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tags: ham_radio satellites awards
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This past Thursday afternoon I received my new Arrow Antenna. It's a dual-band (2m/70cm) handheld yagi antenna made from aluminum arrow shafts for making contacts with amateur radio satellites. What? You didn't know there were ham radio satellites? Yep, and there's more than one.
Using Heavens-Above, I can find when each satellite will be making a pass over my location as well as the angle and direction of the approach and apex. About an hour after I got the antenna, AO-27 was making one of its daily passes over me. I made sure everything was in order, set my radio to the right frequencies and walked to the field across from my house. Right off the bat I heard guys in New England talking with guys in Florida. Most everyone on the air was using a handheld with relatively low power (under 5W, which normally isn't enough to even get you across town). After just a few minutes I heard my chance to throw out my call. Right away I had two stations come back to me. First time to ever hear the satellite and I was making a contact on one. Unfortunately I didn't have a free hand to write down his callsign and I forgot it! Oops!
How does it work? Essentially the little satellite takes my signal and rebroadcasts it like a ground-based repeater does, only it's up - way up. Because it's up so high, it can rebroadcast my signal to most of North America. To hear me all the other station has to do is listen on the "downlink" frequency.
Really it doesn't take any special antenna to allow this, it's just this antenna is very efficient and easy to aim at just the right spot.
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tags: ham_radio antenna satellites
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