Difference between revisions of "Es'hail-2 conference transmissions"

From BATC Wiki
Jump to navigation Jump to search
(Created page with "It has been agreed that the wideband transponder can be used to uplink amateur radio related conferences and presentations. Any transmissions must be agreed with AMSAT-DL bef...")
 
Line 3: Line 3:
 
Any transmissions must be agreed with AMSAT-DL before the event and should last no longer than the actual condference or talk sessions - transmissions of rempty rooms and / or general activities are not permitted as they are taking up transponder bandwidth which could be used for normal DATV QSOs.
 
Any transmissions must be agreed with AMSAT-DL before the event and should last no longer than the actual condference or talk sessions - transmissions of rempty rooms and / or general activities are not permitted as they are taking up transponder bandwidth which could be used for normal DATV QSOs.
  
  A valid amateur radio callsign must be transmitted at all times an it is the user's responsibility to check and comply with their local license conditions.  For example the UK amateur radio license does NOT permit broadcast transmissions and all transmissions must either be a CQ call or a two way QSO.
+
  A valid amateur radio callsign must be transmitted at all times and it is the user's responsibility to check and comply with their local license conditions.  For example the UK amateur radio license does NOT permit broadcast transmissions and all transmissions must either be a CQ call or a two way QSO.
  
 
==Transmission standards==
 
==Transmission standards==

Revision as of 15:50, 5 March 2019

It has been agreed that the wideband transponder can be used to uplink amateur radio related conferences and presentations.

Any transmissions must be agreed with AMSAT-DL before the event and should last no longer than the actual condference or talk sessions - transmissions of rempty rooms and / or general activities are not permitted as they are taking up transponder bandwidth which could be used for normal DATV QSOs.

A valid amateur radio callsign must be transmitted at all times and it is the user's responsibility to check and comply with their local license conditions.  For example the UK amateur radio license does NOT permit broadcast transmissions and all transmissions must either be a CQ call or a two way QSO.

Transmission standards

The conference uplink should use the following transmission standards:

Transmission mode: DVB-S2 (Increases the signal margin by 2 dB and is the recommended standard for QO-100)

Modulation: QPSK (gives the best signal margin)

Symbol Rate: 1.5MS (higher SR needs more power/TX dish size and denies other users the bandwidth, lower reduces compatibility with commercial receivers and potentially reduces video quality) 1.5Ms also reduces any conflict with the 2Ms beacon which can pull station’s FEC off channel.

Frequency: Exact frequency to be used will be confirmed at the time of request but nominal frequency for conference transmissions is 10,494.5 MHz with a .2 roll off when the beacon transmission is on.

Encoding: H264 (H265 would give better picture quality, but increases encoding complexity and decreases receiver compatibility. MPEG-2 does not offer any advantages)

Power Level: The power level should be set to the same as the beacon (using the Spectrum Monitor here: https://eshail.batc.org.uk/wb/ ). This means that anyone who can receive the beacon should be able to receive your transmission.

FEC: 2/3 initially. This could be altered from 1/4 (which would enable reception on much smaller dishes, but reduce picture quality), up to 9/10 (which would give slightly improved quality, but more difficult reception). However, keeping it the same as the beacon with the same power density means that anyone who can receive the beacon can receive your transmission.

Picture format: 720p. I would suggest testing your encoder with 720p to begin with.

Power budget: About 100W to a 1.2M dish should achieve the parameters above (or 25 W to a 2.4M dish...)