Learn, hack!

URL

http://events.ccc.de/camp/2011/Fahrplan/attachments/1885_4597-moonbounce-slides.pdf

File name

1885_4597-moonbounce-slides.pdf

File size

3.4 MB

MD5

cb464fcdeb05cb126d737a2f4204cd5f

SHA1

fb15fcac2a837154b844a07c4c31b6dc80fc0b26

Moon bounce, also known as EME (Earth-Moon-Earth), is a technique that allows two earth-based radio stations to communicate directly by using the moon as passive reflector. It is the longest path two stations on Earth can use to establish direct connection with each other. First developed the late 1940s by the United States Navy it was used as a revolutionary way to communicate without the uncertainties of shortwave radio propagation. The development of artificial satellites completely obsoleted this usecase only a few years later but the technique itself is still one of the most challenging tasks in radio communication. Today it's Amateur Radio stations that are practising the art of Moon bounce. We are here to tell and to show you how it is done. Amateur Radio Operators are one of the oldest sub-groups in the Hacker universe. Long before the term Hacker was coined there were people tinkering in their Shacks, building equipment and trying to communicate with like-minded spirits from all over the world. Moon bounce is not the newest kid on the block in the radio field but still most demanding in terms of necessary equipment as well as operating skills. We provide you with a little historic background, some basic facts about how radio communication even works and then explain what has to be done to achieve the goal of bouncing signals off the moon. In a weird coincidence we will actually have a Moon bounce setup at the camp site so expect some current pictures as well as juicy tales of the radio art. "But wait!" you say, "The moon's only up half of the day". Well, you're right. Remember those artificial satellites that replaced the moon in military as well as commercial applications? We have them too! Amateur Radio Satellites and even the International Space Station can easily be reached with a very modest radio setup so we will explore these communication modes too.