Satellite UO-14

Currently, probably the most accessible satellite for radio amateurs. On QSO in an emergency, a two-band 'FM hand' and an external antenna will suffice. The optimal device would consist of two transceivers: at 2m with a power of 25W, at 70 cm any TCVR (RX is enough) and a pair of antennas (for example, design XE1MEX described recently). With such equipment, it is not a problem to work with the whole of Europe.

Launch into orbit

UO-14 was launched by the Ariane space shuttle from Korou in French Guiana on January 22, 1990. On board is a satellite transponder with an uplink on 145.975 MHz and a downlink on 435.070 MHz. The advantage of FM in satellite operation is that we can largely ignore the Doppler frequency shift - we tune to the 2m uplink frequency and can transmit. At 70 cm, the Doppler is already larger, it is advisable to tune around the downlink frequency so that the reception is as good as possible, while we do not have to listen to our signal on the uplink.

Thanks to sponsors (University of Surrey, ARIANESPACE, VITA, AMSAT, RACAL, RAE, MITSUBISHI, SSTL), it was possible to realize a satellite with dimensions of 345x345x600 mm and a weight of 45 kg for a price of 350 GBP. It was launched by a space shuttle into a sun-synchronous orbit 780 km above the Earth's surface with an inclination of 98°.
On board is: battery module, receiver, transmitter, power system, remote control module, telemetry system, on-board computer (1802), RAM disk, PACSAT communication experiment (80C186), space experiment with particles, positioning, control and safety system. UO-14 has a 2 m dipole antenna and four 70 cm rod antennas, a stabilizer bar, two three-axis magnets and four GaAs solar panels that cover the outer surface of the satellite.

Transponder UO-14

Primárnou časťou UO-14 bol digitálny transpondér typu store and forward, ktorý mohli využiť stovky portablových pozemských staníc. Tento spôsob sa používa najmä v oblastiach postihnutých prírodnými katastrofami, kde iný spôsob komunikácie nie je funkčný. Dva platené projekty sú zamerané na monitorovanie radiácie satelitu na nízkej obežnej dráhe (LEO ), measurement of cosmic particles and total radiation. Power supply is provided by highly efficient GaAs solar cells in cooperation with NiCd accumulators.

Amateur radio transponder UO-14

Po poruche tohto systému sa využíva dnes len rádioamatérsky transpondér. Ten pracuje 24 hodín denne. Pri každom oblete je tam rušno, preto sa komunikácia obmedzuje len na výmenu najnutnejších informácií – značiek, reportov a lokátorov. Platí pravidlo, že ak dve stanice robia QSO, ostatní nevysielajú – ináč by spôsobovali QRM . Ak Vás satelitná komunikácia zaujíma, najlepší spôsob ako si ju vyskúšať sa volá UO-14.