On Wed, 04 Feb 2004 15:42:07 +0000, Peter Hickman <peter@semantico.com> wrote:

Meaning that any communication recieved would be from life forms that
have Hydrogen based life, like ours.

This is where is goes wrong, the hydrogen band is cleaner. There is less 
noise in this part of the spectrum so if you wanted a message to travel 
far and not get swamped with all the background noise then this is the 
frequency you should transmit at.

Hmm...Isn't this the frequency at which ionized hydrogen emits? ie- it is a
frequency that is found commonly in the galaxy. 

The advantage of using it is more likely that the frequency is useable to map
hydrogen gas concentrations in the galaxy, so it's one that civilizations would
be expected to be interested in for astronomy purposes.

That means that it would be an ideal wavelength to transmit on if you wanted
somebody else to see your signal.... send the signal in a way that is likely to
be seen because that's where others would be looking. ('where' in the sense of
frequency band, not physical direction or location)

In addition, there are potential spin offs into other areas of astronomy. Some
of the detected signals might turn out to be not ET's, but some hitherto
unexamined phenomenon emitting in the hydrogen band... and perhaps worth further
investigation in visual, radio, UV, or other bands.