Archived from groups: alt.video.satellite.mpeg-dvb (More info?)
1. Last week I was contracted to do a satellite tv downlink in support
of ESPN who was broadcasting the Maryland/Duke basketball game at
College Park, Md. My downlinked signal was the regular Galaxy 12 ESPN
signal displayed on the jumbotron screen inside the arena and to the
commentators after the game and to the production vans inbetween
events. A separate uplink truck did the pre and post game on site
activities, commentators, etc. Another uplink truck did the game
itself. ESPN had 3 separate production trailers on site. I had plenty
of time to talk with the uplinkers and view their various equipment.
These uplinkers are very, very good at what they do and are frequently
on the go literally across the country at times.
2. The trend in MPEG2 uplinking has been to MPEG2 4:2:2. Each uplink
truck contains a primary and backup for all equipment to include 4:2:2
encoders which were used for the pre/post game activities. One truck
uplinked the pre/post activity to Galaxy 4 Ku band. Uplink power is
about 150 watts. The other uplink truck used about the same power and
uplinked the game on C band. I forgot to ask what satellite, but the
look angles were comparable on both trucks. Antenna sizes were a 15 ft.
Andrew and a 15 ft. Comtech. Both configurations were insured for
$750,000. For DTV and/or Dish Network uplinks affecting services being
broadcast via satellite in real time, the uplinkers carry a portable DTV
or Dish Network antenna and receive the target signal in the truck to
visually confirm the quality of the downlinked signal.
3. MPEG2 4:2:2 baseline is bad enough but reception equipment is
available if you want to pay the high dollar price. Both uplinkers told
me the trend now is to encrypted HDTV and leave the 4:2:2 format. These
HDTV transmissions typically will occupy a full transponder bandwidth.
4. I also did a satellite tv downlink teleconference in January using
an encrypted MPEG2 satellite signal. Thanks to the new generation of
blind search receivers many teleconferences now will be encrypted
MPEG2. My pre-authorized receivers used Nagravision modules, the same
encryption mode as used by Dish Network. The downside of any encrypted
signal is an average of 2 db in signal strength is used in the decoding
process. But the receivers worked worked well. Galaxy 3 Ku band was
used.
5. A number of SNG vans came and went. Ch. 13 from Baltimore did a
live standup and a Ku band uplink. WRC Ch. 4 in DC did a 2 ghz.
point to point microwave link that probably was about a 10-15 air mile
line of site to the tower. All of my concerns about RF interference
were not happening until the Maryland State Police helicopter appeared
with the searchlight and flying very low. He was spewing microwave RF
really bad. The helicopter was flying low over campus to intimidate and
warn any students not to think about rioting. It has infrared
technology on board. The received infrared signal can be relayed
through another microwave transmitter to ground units. I suspect that
link is what caused temporary problems for me. Whenever he would fly in
my look angle line of sight path it disrupted my reception varying from
minor to total wipeout. When he moved on my reception again was great.
Fortunately the ballgame had ended when he appeared on scene and only
the guys in the producation vans had to deal with his temporary RFI.
1. Last week I was contracted to do a satellite tv downlink in support
of ESPN who was broadcasting the Maryland/Duke basketball game at
College Park, Md. My downlinked signal was the regular Galaxy 12 ESPN
signal displayed on the jumbotron screen inside the arena and to the
commentators after the game and to the production vans inbetween
events. A separate uplink truck did the pre and post game on site
activities, commentators, etc. Another uplink truck did the game
itself. ESPN had 3 separate production trailers on site. I had plenty
of time to talk with the uplinkers and view their various equipment.
These uplinkers are very, very good at what they do and are frequently
on the go literally across the country at times.
2. The trend in MPEG2 uplinking has been to MPEG2 4:2:2. Each uplink
truck contains a primary and backup for all equipment to include 4:2:2
encoders which were used for the pre/post game activities. One truck
uplinked the pre/post activity to Galaxy 4 Ku band. Uplink power is
about 150 watts. The other uplink truck used about the same power and
uplinked the game on C band. I forgot to ask what satellite, but the
look angles were comparable on both trucks. Antenna sizes were a 15 ft.
Andrew and a 15 ft. Comtech. Both configurations were insured for
$750,000. For DTV and/or Dish Network uplinks affecting services being
broadcast via satellite in real time, the uplinkers carry a portable DTV
or Dish Network antenna and receive the target signal in the truck to
visually confirm the quality of the downlinked signal.
3. MPEG2 4:2:2 baseline is bad enough but reception equipment is
available if you want to pay the high dollar price. Both uplinkers told
me the trend now is to encrypted HDTV and leave the 4:2:2 format. These
HDTV transmissions typically will occupy a full transponder bandwidth.
4. I also did a satellite tv downlink teleconference in January using
an encrypted MPEG2 satellite signal. Thanks to the new generation of
blind search receivers many teleconferences now will be encrypted
MPEG2. My pre-authorized receivers used Nagravision modules, the same
encryption mode as used by Dish Network. The downside of any encrypted
signal is an average of 2 db in signal strength is used in the decoding
process. But the receivers worked worked well. Galaxy 3 Ku band was
used.
5. A number of SNG vans came and went. Ch. 13 from Baltimore did a
live standup and a Ku band uplink. WRC Ch. 4 in DC did a 2 ghz.
point to point microwave link that probably was about a 10-15 air mile
line of site to the tower. All of my concerns about RF interference
were not happening until the Maryland State Police helicopter appeared
with the searchlight and flying very low. He was spewing microwave RF
really bad. The helicopter was flying low over campus to intimidate and
warn any students not to think about rioting. It has infrared
technology on board. The received infrared signal can be relayed
through another microwave transmitter to ground units. I suspect that
link is what caused temporary problems for me. Whenever he would fly in
my look angle line of sight path it disrupted my reception varying from
minor to total wipeout. When he moved on my reception again was great.
Fortunately the ballgame had ended when he appeared on scene and only
the guys in the producation vans had to deal with his temporary RFI.
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