12 Suggestions for Success Working AMSAT-OSCAR 51 (Echo)

[This was originally posted as 8 suggestions in a post on the AMSAT-BB. Several people wrote to me and asked that I post it on the website, and a few were scratching their heads. It was late after a midnight AO-51 pass when I wrote it, and after reading my post the next morning I decided to add a few things and include a few graphics.
I don't remember who told them to me (KK5DO perhaps) but I'd like to thank all my elmers - you know who you are.]

  1. THE ONE TRUE RULE for HT success (and even for FM base station users) - keep your SQUELCH OFF. If you ignore every other rule in this list, don't ignore this one. Working satellites starts off as a process of finding weak signals, so don't expect the satellite to be anywhere as strong enough to break squelch like your local repeater. I know it's noisy, but that's part of the process. Noise can also be an aid in locating the satellite because when the frequency starts to exhibit QUIETING, that's a sure sign that you are hearing the satellite, and you should get ready.
  2. LISTEN FIRST! Even though you only have 5 watts, it's still possible to jam other stations. Expect to hear other stations before you transmit. If you can't hear other stations and need to check your uplink, don't call CQ, just transmit your callsign. If others hear you, they will want to work you.
  3. Use a good antenna for your HT. A good gain whip antenna like the AL-800 is very good. Using an Arrow dual-band handheld antenna is better, and if you prefer to homebrew your antenna, Alex Diaz XE1MEX has an excellent Yagi-Uda design.
  4. When you identify yourself, always say your CALLSIGN followed by "HANDHELD" - I've found most operators will give way to HT users if they identify themselves that way. "Portable" is also good.
  5. AO-51 Doppler CorrectionSet up your radio so you can to tune for DOPPLER. If your HT only has 5KHz tuning steps, start listening 5 KHz above the center frequency - you will hear the satellite sooner and clearer. When you hear the downlink signals get scratchy or fuzzy, tune down 5KHz and it should be clearer. Follow the signal down in frequency as the pass continues. (See the graphic to the right.) If your HT doesn't allow you to use split frequencies in VFO mode, consider programming a couple of memory channels in this way, then just move to the next memory channel. For 5KHz tuning step radios it's debateable whether or not tuning the transmit frequency is helpful. If you have 1KHz or finer tuning steps it definitely helps.
  6. Facing the SatelliteBack to the satelliteDon't hold your whip antenna upright. Vertical antennas are not good, and a HT held upright isn't either. The satellite isn't on the ground (which is what HT's and vertical antennas were designed for). TILT IT about the same amount as the satellites ELEVATION. This means that if you are FACING the satellite, tilt it down towards the ground from HORIZONTAL an equal amount. If the satellite is to your back, tilt it up an equal amount away from the satellites position off the vertical. You will be surprised at the difference.
  7. Make sure you know where the satellite is. Even if you don't have a palm sized computer running a tracking program such as PocketSat or PetitTrack you can estimate this. If you know the AOS azimuth and the satellite pass time, you can just estimate how much to move until you find the satellite. On ASCENDING (South to North) with the satellite EAST of you or DECENDING passes (North to South) and WEST of you, move your body anti-clockwise (counter-clockwise for people in the US). If the satellite is ASCENDING WEST or DECENDING EAST, move clockwise.
  8. HEADPHONES are very important, especially if you are working full duplex. You are much better off listening with two ears than one. If you have a full duplex HT like a Icom IC-W32A you can listen to your own downlink (a good thing). Your brain is far better at discriminating signals than most expensive DSPs.
  9. Know your gridsquare as that is a quick way of identifying your location. Saying CM87 is much quicker than saying "San Francisco, California". The ARRL and Icom have some dandy gridsquare maps, the latter of which are free at most amateur radio stores. You can download both from the respective websites.North America Population Centers
  10. Map out a strategy for contacts. This isn't rocket science, but close. So preparation and planning is important. Not every pass is workable with an HT, so don't go after the 10 degree passes. Pick your passes, and work the ones you know will give you the best chance. It's not a battleground out there, but it's not a walk in the park either. You are competing with other stations for a limited resource so it helps to plan. If there are population centers (bright spots on the map) to the east of you, work western passes. If they are south of you, listen north. If you live on the coast, try passes out over the ocean.
  11. If you don't plan to write down your contacts, try to work out someway to record them. You can hook a MP3 or Cassette recorder into the headphone jack on the receive side to record your contacts so you can review it later. On many HTs you can just use a simple "Y" cable available from Radio Shack. Even if you don't make contacts, it helps to accustom yourself to the callsigns, voices and personalities of the other operators. When I first started out, I found it more valuable to know which contacts I missed rather than the ones I made.
  12. Ask questions! Find an elmer or look up the AMSAT area coordinator for your area. You can locate an Area Coordinator on the AMSAT website. Posting specific questions on the AMSAT bulletin board will also help you find answers.
Most of all - Join AMSAT! It will help you get plugged in to a very good organization, keep you informed of the latest developments, and contribute to the success of the amateur satellite program.

Contributed by Emily Clarke W0EEC,
AMSAT Area Coordinator, San Francisco Bay


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