Amateur radio operators use many different ways to get signals from one spot to another. Perhaps one of the most interesting is meteor scatter propagation.
Meteor scatter propagation is possible because when a meteor strikes the Earth’s atmosphere, a cylindrical region of free electrons is formed at the E layer of the ionosphere. (E3A08) 28 – 148 MHz is the frequency range that is well suited for meteor-scatter communications. (E3A09)
Unfortunately, these ionization trails are relatively short-lived, so to communicate via meteor scatter, you need to either be able to detect when these paths are available or be transmitting when the paths are available. All of these choices are correct when talking about good techniques for making meteor-scatter contacts (E3A10):
- 15 second timed transmission sequences with stations alternating based on location
- Use of high speed CW or digital modes
- Short transmission with rapidly repeated call signs and signal reports
For more information on meteor scatter, go to:
Sebastian - W4AS says
Is this question actually part of the Extra exam? If so, it’s not entirely correct. The commonly used bands are 50 and 144 MHz, however 222 MHz is also suitable for meteor scatter contacts. And when there’s a shower, contacts can and are made on 432 MHz as well.
30 second exchanges are the norm, not 15 seconds.
And the biggest mistake is the part about short transmissions. Transmissions of the same information, whether it be CW or digital, is done continuously throughout the 30 second period.
Dan KB6NU says
Those questions and answers are taken verbatim from the new Extra Class question pool.