On 13 Jun 2004 02:16:14 GMT, (Mediaguy500)
wrote:

I guess that means no more space shuttle video on 2250 mhz any more in a few
years or so, if it could even be picked up on the R3 in the first place (which
it might not ever been abvle to do anyways since the S band transmission might
be both encrypted and digital.)

Downlinked data from the shuttle is on something called Unified S
Band, or USB.

This is voice, tons of telemetry data, video (all digital, no analog)
and anything else needing to be transmitted, all multiplexed together.

It's linked through a TDRSS satellite then to the ground. Shuttle
transmit power is very low, and it doesn't take much to hit a TDRSS.
(Tracking Data Relay Satellite System, or basically a repeater).

Ground stations have antennas large enough to set your house inside.

The R3 is nearly deaf to any video, but you are correct, the shuttle
is all digital, so it's a moot point anyway.

The USB has to be demuxed into its separate components. Not practical
at a small scale.

Steve WA3SWS

former NASA employee, tho pre-Shuttle


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