En ny satellit från Sydafrika med amatörradio ombord är på gång. Vi känner igen upplägget med Voice Digipeater och en enkel V/U transponder:
It is official! South Africa’s second satellite, SumbandilaSat, will be launched from the Russian Baikonur Cosmodrome in the December to March time frame.
SumbandilaSat has been unpacked and is undergoing testing at SunSpace in Stellenbosch before it will be shipped to Russia for integration with the launch vehicle. Engineers at the launch site are preparing a special adapter ring to accommodate the Sumbandila structure on the rocket.
“Sumbandila” means showing or pointing the way. Freely translated into English “Pathfinder”
The Amateur Radio Payload will be operating in conjunction with the University of Stellenbosch Software Defined Receiver project as it will share the VHF receiver and UHF transmitter used by the SDR project.
SA AMSAT has designed and built a control system to facilitate the following
operations:
* V/U voice transponder with an uplink in the 2 metre band and a downlink in
the 70cm band.
* A parrot repeater (voice digipeater)
* A voice beacon
The control unit will command the various function of the transponder and handle the parrot and beacon messaging. On receipt of a tone from the VUCU VHF receiver, the CTCSS tone will be decoded and depending on the tone received the unit will command the VU transponder operation or the parrot repeater. In the transponder mode the satellite will act like a cross-band FM repeater and allow two way communications with other stations on the ground.
If the tone received indicates parrot operation, the interface unit will record 20 seconds of audio on its VHF uplink receiver and replay the recorded audio on the UHF downlink.
Should, for a predetermined period, there be no tones received, the controller will initiate a voice beacon, transmitting a pre-recorded message at regular
intervals. This facility will offer many opportunities for educational
projects.
[ANS thanks SA AMSAT for the above information]