Path: utzoo!attcan!uunet!zephyr.ens.tek.com!orca!pogo!bobt
From: bobt@pogo.WV.TEK.COM (Bob Tidrick)
Newsgroups: sci.space.shuttle
Subject: Re: Shuttle communications
Summary: Here is a file I saved some time ago with Shuttle frequencies.
Message-ID: <7651@pogo.WV.TEK.COM>
Date: 26 Jul 89 18:16:54 GMT
References: <115800001@uxa.cso.uiuc.edu> <807@occrsh.ATT.COM>
Organization: Tektronix Inc., Beaverton, Or.
Lines: 43

This was saved from the net maybee two years ago. I don't know if they are
still current but I can't see why they would not be.

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The shuttle comm frequencies are public information. From my Rockwell
STS-1 press kit, the three UHF AM frequencies are: 296.8 (primary),
259.7 (secondary), and 243.0 Mhz (emergency).

The S-band frequencies are:

2287.5 Mhz (PM downlink - primary)
2217.5 Mhz (PM downlink - secondary)
2250.0 Mhz (FM downlink - primary)
2205.0 Mhz (FM downlink - development flight instrumentation)
2106.4 Mhz (PM uplink - primary)
2041.9 Mhz (PM uplink - secondary)
1831.8 Mhz (PM uplink - DoD primary)
1775.7 Mhz (PM uplink - DoD secondary)

As Ron said earlier, the data stream is multiplexed stuff with digital
voice and telemetry. However, all of the data formats are also public
information. I have a NTIS report on the performance of the
communications system during the STS-2 ascent, and in an appendix are
complete details on everything you need - frame sync vectors, channel
assignments, etc. In addition to the digital data, the PM downlinks
repeat a 1.7 Mhz ranging tone. For the non-DoD uplinks, the carrier
frequency of the downlink transmitter is phase locked to 240/221 times
the uplink frequency, also for tracking.  While certainly challenging, this
is not outside of the capabilities of a dedicated amateur.

The FM downlinks can carry a variety of stuff, e.g., television [probably
analog], 128 kb/s real-time engine data or 192 kb/s playbacks of
recorded data.

Phil
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                                                 From the Files of
                                                 Bob Tidrick
                                                 GPID Engineering
                                                 Tektronix Inc.
                                                 Wilsonville OR.