HISTORY.
Date December 1961.
Today there are several radio amateur satellites orbiting the earth
using analogue, digital and imaging techniques as well as those designed
specifically for emergency communications in the event of a natural catastrophe
such as a Tsunami.
Amateur radio has always been at the leading edge of satellite
technology and satellites like the soon to be launched P3D EXPRESS will utilise
systems not yet tried in the commercial world.
It all started 44 years ago in December of 1961 when Oscar 1. OSCAR
is an acronym for: Orbiting Satellite Carrying Amateur Radio. With its battery
powered beacon began orbiting the earth transmitting the familiar letters 'HI'
in Morse code.
Between Oscar 1 and the current fleet of amateur radio satellites
there have been and will continue to be a host of opportunities for the amateur
radio satellite enthusiast, some of the satellites in low earth orbit (LEO)
providing simple CW and SSB communications for radio amateurs around the world,
others in high elliptical orbits providing DX contacts or store and forward
'flying mailboxes' using advanced digital techniques. P3 EXPRESS like it's
predecessor P3D is expected to have advanced imaging systems and an estimated
life of at least 20 years! ... taking us well into the 21st century.
NOTE.
Until recently, The Amsat Corporation (an international group of
amateur radio satellite enthusiasts) together with the Russians were the only
ones to have built satellites with amateur radio transponders but on the 5th of
May 2005 India launched its first amateur satellite, HAMSAT on board an Indian
built PSLV launch vehicle from the Sriharicota test range.
Amateur satellites were launched in 'phases'- Phase 1 satellites
were simple low Earth orbit types carrying radio beacons. Phase 2 satellites
were more sophisticated low Earth orbit types carrying beacons and
transponders. Phase 3 satellites are placed into highly eccentric orbits and
carry more sophisticated transponders, beacons and onboard propulsion systems.
This booklet will provide the newcomer with all the necessary
information to be able to utilise these satellites, be they analogue or
digital, LEO's or high fliers, imaging
satellites or flying mailboxes.
Each satellite has it's own 'character' and provides specific modes
of communication. Satellite operating is the 'cutting edge' or 'sharp end' of
amateur radio, like P3E EXPRESS with it's high microwave frequencies, while
satellites like HAMSAT provide a simple training ground on the lower
frequencies with its VHF and UHF links.
In other words ... something for everyone!