P4-A WB Transponder Bandplan and Operating GuidelinesSeptember 17, 2018
The following operating guidelines and bandplan are designed to enable the most efficient use of the 8MHz wide transponder for all users.
Due to the very large number of variations of transmission parameters, it is essential that all users notify their transmission parameters on the co-ordination chat room page that has been established by AMSAT-DL and BATC at the Qatar-OSCAR 100 Wideband Spectrum Monitor which is hosted at the Goonhilly Earth Station in Corwall, UK.
As a general principle, the transponder should be only be used for short-duration tests and contacts.
The only long duration (more than 10 minute) transmissions should be:
- The TV beacon channel uplinked from Qatar (A71A) or Bochum (DK0SB).
- Video of the live proceedings of AMSAT and Amateur TV Lectures and Conferences of wide interest. Examples might include:
- National AMSAT Conferences
- National Amateur TV Conventions
The following content is unacceptable:
- Recordings of events, or broadcast of events not explicitly concerned with Amateur Satellites or Amateur TV
- Transmission of any copyright material (such as movies or TV channels)
- Repeated transmission of test videos unless essential for equipment alignment
- The relaying of terrestrial Amateur TV Repeaters is discouraged unless the content is of exceptional amateur radio interest.
All uplink transmissions should use the minimum power possible. QPSK transmissions should have a downlink signal with at least 1 dB lower power density than the Beacon – the web-based spectrum monitor enables users to set their uplink power to achieve this. Transmissions with symbol rates of less than 333 kS using 8PSK, 16 APSK or 32 APSK should use the minimum power density required to achieve successful reception.
Transmissions should use DVB-S2 where possible. For normal standard definition transmissions, 2 MS is the maximum symbol rate that should routinely be used.
To enable easy decoding the following DVB PIDs are recommended: Video 256, Audio, 257, PMT 32 or 4095, PCR 256 or 258. Service Name should be set to CallSign. PMT PIDs 4000 – 4010 should not be used.
On Wednesdays (UTC time), experimenters are encouraged to try other modes – perhaps 6 MS using the whole transponder for brief (less than 10 minute) periods. It is essential that users announce their plans on the chat room page, and always monitor it.
Experiments using unusual modes (for example ranging) should use the lower 1.5 MHz of the “Wide and Narrow DATV” Segment.
The beacon transmits continuously (24/7) to provide a test signal and to allow new users to precisely align their antennas.
DATV Beacon DVB-S2 parameters:
- Center Frequency: 10.4915 MHz
- QPSK 4/5 FEC
- 1500 kSymbols
- RollOff = 0,25
- Pilots = off
- min. C/N = 4.6dB
- Datarate 2.383 MBit
Bandplan (V2.0 2020)
- Narrow DATV transmissions should be confined to the “Narrow DATV” section, but may use the “Wide and Narrow DATV” section if the Narrow DATV section is fully occupied.
- A maintenance uplink occupying 10494.0 MHz – 10497.0 MHz will be used very occasionally; users are requested to give it absolute priority when notified.
- Recommended spot frequencies for various usages and symbol rates are listed below.
- Uplink 2401.0 – 2410.0 MHz RHCP, Downlink 10490.5 – 10499.5 MHz Horizontal.
|Mode||Symbol Rate||Uplink Freq MHz||Downlink Freq
|Beacon||1500 kS||2402.0||10491.5||Beacon DVB-S2 FEC 4/5|
|Wide||1 MS||2403.75||10493.25||1.5 MS and 2 MS transmission should use this part of the band|
|Narrow||333 kS||2403.25||10492.75||Use these 14 frequencies for
500 kS, 333 kS and 250 kS
Use frequencies above 10497.0 first
|Then every 500 kHz until|
|Very Narrow||125 kS||2403.25||10492.75||Use these 27 frequencies for
125 kS, 66 kS and 33 kS
Use frequencies above 10497.0 first
|Then every 250 kHz until|
|Very Narrow||125 kS||2409.75||10499.25|