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If you want to pick up NASA TV's new digital 
signals, please pass this technical information 
along to your A/V staff; a glossary of terms is 
included.  The official info page is: 
http://www.nasa.gov/multimedia/nasatv/digital.htm. 
NASA will update this Web page as new information 
becomes available. E-mail questions or concerns 
to 
<mailto:[log in to unmask]>[log in to unmask]


Satellite Downlink for continental North America:
Uplink provider = Americom
Satellite = AMC 6
Transponder = 17C
72 Degrees West
Downlink Frequency:  4040Mhz
Polarity: Vertical
FEC= 3/4
Data Rate= 36.860 Mhz
Symbol = 26.665  Ms
Transmission = DVB
"Public" Programming:  Program = 101,   Video PID = 111,   Audio PID = 114
"Education" Programming:  Program = 102,   Video PID = 121,   Audio PID = 124
"Media" Programming:  Program = 103,   Video PID = 1031,   Audio PID = 1034
"SOMD" Programming:  Program = 104,   Video PID = 1041,   Audio PID = 1044


Satellite Downlink for Alaska and Hawaii (beginning July 2005):
Uplink provider = Americom
Satellite = AMC 7
Transponder = 18C
137 Degrees West
Downlink Frequency:  4060Mhz
Polarity: Vertical
FEC= 3/4
Data Rate= 36.860 Mhz
Symbol = 26.665  Ms
Transmission = DVB
"Public" Programming:  Program = 101,   Video PID = 111,   Audio PID = 114
"Education" Programming:  Program = 102,   Video PID = 121,   Audio PID = 124
"Media" Programming:  Program = 103,   Video PID = 1031,   Audio PID = 1034
"SOMD" Programming:  Program = 104,   Video PID = 1041,   Audio PID = 1044

NOTES:
1.  SOMD = Space Operations Mission Directorate
2.  PCR (program clock reference) information is 
included within the Video PID by the Harmonic 
Encoders used by NASA TV

GLOSSARY OF TERMS

"Addressable" – A type of IRD (Integrated 
Receiver Decoder) that can not only receive "free 
to air" digital TV signals but can also receive 
and store specially encrypted programming for 
rebroadcast.

DVB – Digital video broadcast.

FEC – Forward Error Correction

"Free to Air" – A TV channel that local cable and 
satellite service providers are "free to air" at 
no cost. Your basic, commercial "off-the-shelf" 
IRD can tune a "free to air" digital TV channel, 
provided you have a C-Band-size satellite 
receiving dish.

IRD - Integrated Receiver Decoder, a piece of 
equipment used to tune a digital TV signal.

LNB – Low Noise Block/Converter.

NTSC – National Television System Committee. The 
group responsible for setting the television and 
video standard used in the United States. NTSC 
also refers to the standard itself. (In Europe 
and elsewhere, PAL and SECAM are the dominant 
standards.)

PID – Program Identifier

SOMD – Space Operations Mission Directorate

TBD – To Be Determined.

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