B Do we currently have interstellar com capabilities?

[newjerseyrunner]

In 1974 we sent a signal out towards a cluster of stars 25,000 light years away at a power of 1000kW. If we had been on the receiving end of that signal, would we have been able to detect it? Basically if you could have two identical Arecibo observatories, what's the maximum range in which they could talk to each other?

 

[Chronos]

The 1974 message beamed by arecibo was mostly media hype. It is unlkely to be recognized by another arecibo at that distance. A more realistic range for an arecibo style transmitter is about 10000 light years, which is still pretty impressive, as noted here http://www.setileague.org/articles/oseti.htm. 10,000 light years would span about half way to the galactic center and, more importantly a significant fraction of the Orion arm of our galaxy - where most stars in the putative galactic habitable zone are believed to reside