This will also be the occasion to officially put the two amateur radio transponders of Qatar OSCAR-100, the first geostationary P4-A satellite from Qatar, into operation. The opening ceremony will be held by His Excellency Abdullah bin Hamad Al Attiyah, former Deputy Prime Minister of Qatar. A71AU is also the chairman of the Qatar Amateur Radio Society (QARS) and initiator of the first Qatari amateur radio satellite.
Only after the official release ceremony on February 14 will the transponders be released for general radio operation by radio amateurs worldwide.A team of the P4-A team of AMSAT-DL, consisting of the chairman Peter Gülzow DB2OS, Achim Vollhardt DH2VA and Thomas Kleffel DG5NGI, is on its way to Qatar to set up and commission the P4-A ground segment at the ground station of Es’hailSat. In addition to LEILA and the DVB-S2 DATV system, this also includes a club station for SSB radio operation under the callsign A71A. A backup station is installed at QARS in Doha. The ground station of the AMSAT-DL at the observatory Bochum is also ready for reception and transmission. Later, radio operation via Qatar-OSCAR 100 will also be carried out here under the callsign DL50AMSAT.
During commissioning, we expressly request that you refrain from any transmission attempts!
The SCC in Qatar, as well as Bochum in Germany, are carrying out some tests to measure both transponders and to calibrate the ground systems.
Please also note the beacons sent in the NB transponder. On the DATV beacon of the WB Transponder a video of Es’hail-2 will be broadcast in an endless loop in DVB-S2 format on the opening day.
Again: Please no uplink attempts until the official release of the transponders by QARS!Furthermore, the rules of the game, as defined in the Operating Guidelines for the Narrowband transponder and Wideband transponderare formulated. Please observe the band boundaries of the NB transponder as defined by the upper and lower beacon! A later adaptation and possible extension upwards may be considered after first experiments.
We appeal to patience and to the Ham Spirit: any disruptions during commissioning and on the opening day could result in further postponements of the official release.
Source AMSAT-DL https://amsat-dl.org/en/eshail-2-qo-100-teleport-inauguration
Es’hail-2 Narrowband amateur radio transponder operating guidelines
Es’hail-2 Wideband amateur radio transponder operating guidelines
Es’hail-2 WebSDR enables you to receive both the Narrowband and Wideband transponders online
Es’hail-2 amateur radio information
Es’hail-2/P4-A Narrowband Transponder Operating Guidelines and Band Plan
The narrowband transponder is intended for conventional analogue and narrowband digital signals.
No transmissions should be made beyond the nominal edges of the transponder passbands. In particular, no operation should take place below the lower beacon nor above the upper beacon.
No uplinks should result in downlink signals that are stronger than these beacons. In the event that such signals are detected, they will be marked by a “LEILA” siren. When they have been marked by “LEILA”, operators should immediately reduce their uplink power (ERP).
No FM transmissions should be made to Es’hail-2 as these would use excessive power and bandwidth.
Although there is no formal bandplan, the following details are provided for initial guidance.
|Uplink [MHz]||Downlink [MHz]||available Bandwidth [kHz]||notes|
|10489,550 – 10489,555||do not transmit||Lower beacon, 400 bit/s BPSK or CW|
|2400,055 – 2400,100||10489,555 – 10489,600||45||CW Only|
|2400,100 – 2400,120||10489,600 – 10489,620||20||narrowband digimodes (500 Hz max. BW)|
|2400,120 – 2400,140||10489,620 – 10489,640||20||digimodes (2700 Hz max. BW)|
|2400,140 – 2400,190||10489,640 – 10489,690||50||mixed modes (2700 Hz max. BW)|
|2400,190 – 2400,295||10489,690 – 10489,795||105||SSB only|
|10489,795 – 10489,800||do not transmit||Upper Beacon, 400 bit/s BPSK or CW|
- above Frequencies are preliminary and will be confirmed/updated after launch.
- NO FM mode is allowed on the transponder.
- No transmission below the lower beacon and no transmission above the upper beacon.
- The NB transponder is a bent-pipe transponder and non-inverting.
- Uplink polarization is RHCP (right-hand circular polarization).
- Downlink polarisation for the NB transponder is V (vertical linear polarisation).
- Monitor the beacons and keep your own signal level below, otherwise you might trigger LEILA warnings.
- Please use minimum uplink power (ERP) .
- Full-Duplex operation is mandatory (you must be able to monitor your own downlink while transmitting!)
- The beacons are modulated in 400 bit/s BPSK (similar to the P3-satellites) or in CW.
- The beacons are generated by the groundstation and will provide selected telemetry from the main satellite related to our amateur radio transponders. Details are still to be defined and will be published later.
Source: AMSAT UK
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