From the moment that AMSAT first lobbed an OSCAR (Orbital Satellite Carrying Amateur Radio) into space, communication via the growing constellation of amateur radio satellites has held a special allure.
Interested in getting active on the sats? A great place to start is to visit amsat.org. The Radio Amateur Satellite Corporation was founded in 1969 and has been advancing the art of space science ever since. AMSAT’s followers were instrumental in the design of OSCAR 1, the first amateur radio satellite that plied the heavens just months after the launch of Sputnik. Amsat.org is loaded with tools for beginners and experienced satellite enthusiasts alike. AMSAT’s book, Getting Started with Amateur Satellites is a great resource and well worth the investment. I hope you will support AMSAT by joining their ranks.
If you’re like me, you’ll want to move from the rudiments of hand-held radios and FM-only operation to a setup that gives you the broadest access to the largest number of birds. Here’s what two of my most trusted mentors recommend.
Two Radios Facilitate Full Duplex
W9WSW’s Satellite Gear – Two Yaesu FT-818s, a Tracer LifePo4 Battery Pack and a Tascam DR40 MP3 recorder.Find a pair of Yaesu FT-817 (or the new 818) radios. These are long time favorites in the low power (QRP) space as they feature all modes in virtually every amateur band, including 2 meters and 70 centimeters. Why two units? Paul Stoetzer – N8HM is, at this writing, Executive Vice President at AMSAT. He says that you’ll want to be able to hear yourself on the downlink to ensure you’re signal is getting into the system. It’s also easier to compensate for the doppler effect by adjusting the 440 frequency as needed during the pass. Although 817s can be found on the used market and will serve your needs well, the 818 has a few convenient updates including an improved battery, better frequency stability and a bit higher power. An added benefit is that you’ll have an excellent radio for low band and mobile work that has many fans in the QRP community. Add a linear amplifier if you want to throw some more heat on HF. If you are a Morse enthusiast, consider equipping one of the radios with the YF-122C 500Hz CW Filter.
It’s all about the gain.
While it is technically possible to work some satellites with a whip antenna and a handheld, serious chasers will want the gain offered by the Arrow 146/437-14BP. This handheld dual band yagi design allows for quick and easy orientation as the polarization of tumbling satellites is continually changing. The antenna is offered with and without a duplexer. In a dual rig configuration like the twin Yaesu solution, you won’t need a duplexer. What you will want is a pair of low-loss coaxial cables with BNC connectors on each end. It’s possible to purchase the antenna with the duplexer built in, but you’ll need a second one to split the signal again. Remember that every passive device also adds signal loss. Another antenna option is the smaller Elk 2M/440L5. It’s a 5 element log periodic that can work across both bands with ease. You’ll see Paul using one in the video, below.
An option for Juice.
Sean Kutzko – KX9X has been a contester and satellite enthusiast for years. He recommends the Tracer 12V 7Ah LiFePO4 Battery. It’s a lithium Ion power pack with the muscles of the best sealed lead acid models. Install Anderson Powerpole connectors all around to make it easy to swap power sources and make sure everything is properly fused.
Choosing headphones.
A good pair of over the ear headphones that will stay in place in challenging environments can make a huge difference. The Vibroplex Inrad is that latest and greatest in this space. It comes with stereo headset connections facilitating multiple radios and a 600 ohm microphone element that is perfectly matched for your transceivers. Heil also has a variety of excellent headsets to choose from. I have a Pro 7 that is a favorite, if a bit pricey resident in my shack.
Make sure to get the right adapters to connect your headphones with your radio. Another good addition is a splitter cable to link the rig audio with an MP3 Recorder. Any inexpensive recording device with a line/mic input can work. You’ll use the recorder as your logging device since both of your hands will be occupied with antenna and radio adjustments on the fly. You will also want to pick up an assortment of BNC to UHF adapters to make for easy connections to your favorite low band antenna.
Putting it all together
Once you have your gear, powerpoles and jumpers ready to go, you’ll want something to hold the electronics while your are operating. Amazon sells an inexpensive camera bag that can get the job done. Check out the photo, above, to see how Sean arranges his gear for easy transport and quick setup. The bag has a long strap that you can throw over your shoulder, holding the rigs in place as you operate.
Operating.. Worth a separate blog post.
Working the sats is as much an art as it is a science. Smartphone applications exist to help you find when and where the birds will make their appearance, even helping you zero in on the frequencies to use. We’ll write a more detailed post on satellite operation later, but here’s an interview with Paul – N8HM, one of the best sat ops around, to whet your appetite.