If you haven’t tried satellite operations, I heartily encourage you to check out this amazing yet easily accessed segment of our amateur radio hobby.
Ham Radio Satellites in Orbit
There are currently a number of amateur radio satellites on the air. While it’s no small matter to build and launch a satellite, it is becoming much more common. From piggy-back riding on other satellite launches to getting onto the International Space Station and tossed out the window, so to speak, there are many ways of getting into orbit.
There are two primary types of satellites: FM and SSB/CW satellites. The FM satellites currently include AO-85, AO-91, and AO-92. They use a single uplink channel and downlink channel. You can think of them as repeaters traveling at 17,500 miles per hour at roughly 300 miles above the earth. These three satellites have a 70 cm uplink frequency and 2 m downlink frequency. That means that your transmitter needs to be on 70 cm and receiver on 2 m. It also means that you can listen on 2 meters and hear your own transmitted signal repeated through the satellite. This is called full duplex versus half duplex when you can only hear when you’re not transmitting.
The SSB/CW satellites currently in operation include XW-2A, XW-2B, XW-2F, CAS-4A, and CAS-4B. These satellites are not limited by a single channel. Instead they have a linear bandwidth that allows several stations in QSOs at the same time. You still have one band for uplink and another band for the downlink.
As you may have guessed, you cannot see these satellites at all times. In fact, their visibility is typically around 10 minutes from the time the satellite appears above the horizon, travels across the sky, and disappears beneath the opposite horizon.
To find the times that satellites will be overhead you can use a smart phone app, computer program, or go online. AMSAT (The Radio Amateur Satellite Corporation) has an online calculator (https://www.amsat.org/track/index.php). You enter your location either from your grid square or latitude/longitude, select the satellite, and it will provide a listing of the satellite passes. That list will include dates and times for AOS, acquisition of satellite, the azimuth of the satellite, the maximum elevation, and the LOS, loss of satellite. This will help you determine when and where to point your antenna to connect with the satellite. It sounds a bit complicated, but once you’re got the process down it becomes second nature.
Satellite Ground Stations
Satellite operation, for all its out-of-this-world implications, doesn’t really require all that much in the way of equipment. A simple hand-held Yagi or log-periodic antenna works very well. Plus, a handy talkie can be used as the uplink transmitter and another one can be used for the downlink receiver. There are lots of possibilities for transmitting and receiving.
It does require a bit of skill, acquired by getting on the air, to line up the transmit and receive frequencies to hear yourself on the satellite, and to track the station on the other side of the QSO. It also takes a bit of skill to determine satellite orbits and where to point your antenna at the right time. All that just takes some practice to get it right.
And, of course, you can always improve your station. That could include adding a VHF/UHF satellite transceiver such as the Icom IC-9700. This rig is all set for satellite operation including receiving the downlink signal at the same time you’re transmitting — full duplex. You can also add computer control of the transceiver’s uplink and downlink frequency.
Another improvement is to use higher gain antennas that track the satellite’s azimuth (direction around the compass) and even elevation. Simple Yagis for 2 meters and 70 cm can be controlled by a small television rotator for azimuth and the antennas can be tilted upward around 15 degrees to cover the elevation of most satellite passes. Even better, you can use a rotator system that controls both azimuth and elevation. You can also interface the rotator system to your computer and let the software point the antennas.
Simple home station satellite antennas for 2 meters and 70 centimeters. A 15-degree elevation angle catches most satellites except when they are directly overhead.
My Home and Portable Station
As with most things in amateur radio, you can build as simple or complex a station as your heart desires and budget allows. For my station, I currently use the Icom IC-9700 Direct Sampling VHF/UHF Transceiver along with MacDoppler as the software controlling the rig’s frequency.
Satellite tracking system display using MacDoppler software. It’s showing my location, with the cross, the direction to the satellite, AO-92, and the track of the satellite. Note the other satellites that are also nearby.
At home I’ve used simple fixed elevation Yagis and found them excellent. At the moment I’m using omnidirectional eggbeater antennas. They get me on the air but don’t work all that well unless the satellite is nearly overhead. These are, however, versatile antennas that also allow local repeater and even SSB/FT8 QSOs.
My portable setup uses a battery to power the IC-9700, a laptop to control the frequency, along with a hand-held Arrow antenna. This setup works exceptionally well in activating grids in rover mode. You can see this in the nearby photos.
Portable station set up from the back of my SUV in grid DM95 using IC-9700 and MacDoppler.
Working Satellite DX
With satellites you will only hear stations that are in the footprint of the satellite. For the maximum distance you’ll be at one edge of the coverage pattern and the DX station at the other end. Some of my best DX from here in North Texas has been Alaska, Azores, Hawaii, and Northern Ireland. Even so, working grids in the USA can be a great deal of fun. There are 488 grids in the continental United States and it’s very, very difficult to collect them all.
Being the DX
That’s where grid expeditions come into play. As noted above, you can get on satellites with a handy talkie and a hand-held antenna. That makes activating a rare grid pretty easy. Well, of course, you have to get there first.
One thing to take into account is that those rare grids can be relatively nearby. They just don’t have any satellite operators, which is why they are rare. That makes for a fairly straightforward drive to reach a new grid, or you can even locate a borderline between two grids and activate them both at the same time. Activating a four-way grid line corner, putting four grids on the air at the same time, can really draw satellite operators.
That’s also what makes satellite operating fun. There is always something going on, new grids, new satellites, and quite a few new operators as they discover the magic of working ham radio stations through space.
My Recent Grid Activation
For this past Thanksgiving holiday, my wife and I visited my daughter and her husband in Amarillo, Texas. They are located in grid DM95 which is not a rare grid but one that doesn’t get on satellites all that often. So, I tossed my gear in the car and set up for satellite QSOs the day after Thanksgiving while my wife and daughter headed out for some shopping.
Satellite portable operation from DM95 Amarillo Texas during 2019 Thanksgiving holiday.
I had two satellite passes that worked well around noon that day, AO-92 and AO-91. These are both FM satellites and very active. As I set things up for AO-92, my software got all sideways trying to find the database of satellite frequencies. By the time I figured out what was happening and managed to restore things, the satellite had crossed the sky and was near the horizon. Dang. I’m sure you’ve encountered similar situations.
For the AO-91 pass, all was well. I picked up the signal early and listened closely to who was on the air. One operator had set up on a grid corner — activating four grids for one contact. So, I tried to let that work itself out. This is necessary when you’re on an FM satellite as everyone has to use the one channel that’s available.
Later in the pass, things opened up a bit and I was able to work four stations and put grid DM95 into their logbooks. It’s nice to help out other hams with their pursuit of operating awards such as VUCC with a satellite endorsement for working 100 grids.
Over the years I’ve also activated a few gridlines: DM74/DM84 in New Mexico, EM05/DM95 on the Texas Oklahoma border, and EM22/EM23 in Texas. That was a great deal of fun and generated lots of interest and activity from other operators who wanted to add those grids to their logs.
Satellite portable operation from the DM74 and DM84 gridline in eastern New Mexico.
Grins
hat’s where the grins come into play — either working a new grid or activating one on a grid expedition. The community of satellite operators is a super open group of people, welcoming you into this aspect of our hobby, and offering any assistance needed. So, it is sweet to be able to return the favor of activating grids. After all, they’ve helped me add over 500 grids to my logbook.
If all this sounds of interest, for more information I recommend the AMSAT website and in particular their book Getting Started with Amateur Satellites. This book is updated every year with new satellites and covers entry level topics extremely well. Here’s the link (https://www.amsat.org/product/2019-edition-of-getting-started-with-amateur-satellites/).
Get on the air with satellites — have fun!
