Clipped from a sci.space.news posting about 'Rock' and 'Roll' - the
two XM Radio satellites... 10,000 watts may not be accurate, but it
isn't too far off...


The XM "Rock" satellite has two 16.4 ft folding deployable S-band
transmit
reflectors and one X-band global receive antenna. The satellite spans
132.5
feet in length and 46.6 feet in width, with antennas fully deployed,
and has
a total spacecraft power of 18 kilowatts. To generate such high power,
each
of the satellite's two solar wings employ five panels of
high-efficiency,
dual-junction gallium arsenide solar cells developed by Spectrolab,
Inc., a
Boeing Satellite Systems subsidiary.

To provide 15 years' service, the Boeing 702 carries the flight-proven
xenon
ion propulsion system (XIPS), built by Boeing Electron Dynamics
Devices,
another Boeing Satellite Systems subsidiary, for all on-orbit
maneuvering.
The satellite carries a digital audio radio payload which features two
active transponders generating approximately 3,000 watts of radio
frequency
power, making these the most powerful commercial transponders ever
built.
Rock is operating in a geosynchronous orbit at 85 degrees West
longitude and
weighs approximately 10,284 pounds (4,666 kg) at launch.



"Dan Luke" wrote in message ...
Have you been ableto obtain any hard specs on the system? The two reps I
spoke to at their both were the most clueless inndividuals I've ever seen
rep'ing a vendor at OSH. For instance, they didn't know what I meant by
"baud rate." Thus I was highly skeptical of some things they told me: that
the WxWorx radar map resolution is 1/4 mile, and that their two satellites'
radiated power is 10,000 watts.