[BC] Failing XM Radio

[Dana Puopolo]

XM used to cover things fine with two birds (named Rock and Roll). A few years
into things, it was discovered that the power supply was wearing out MUCH
faster then planned  (as in the birds would wear out 5-7 years earlier then
had been designed/planned). Boeing and Lloyds of London put the third bird
into orbit at no cost to XM. By adding the third satellite, they were able to
reduce the transponder power of the other two to the point where they will
have a nearly normal life cycle. XM also has a ground spare satellite,

-D 

From: Alan Alsobrook <radiotech at bellsouth.net>

RokprtMike at aol.com wrote:
> GEO spacecraft isn't something that you have as spares. They build them,
launch them, and hopefully sell transponder space on them.

I don't know what XM has ready, but I do know that Sirius has or had a
4th satellite built and "ready to go" if needed. It would be launched
from Russia, and may be in storage over there. Sirius has 3 birds in an
figure 8 orbit over North & South America. If one of those three failed
  service would most likely be a bit more prone to dropouts, but they
would not be "Off the Air".