[time-nuts] Using lasers for data transmission

[Perry Sandeen]

Hi,
Several (many?) years ago National Geographic magazine show a picture taken here in southern California of the state government sending red laser signals between different mountain tops to keep track what was going on near fault lines.
There were no technical details on what was taking place.  So it can be done.
At a hamfest a few years ago I bought both a red and green 35 mW laser pen for about $15 each.  They do shine a long, long way.  Whether these are powerful enough, or can be properly modulated for what is needed, I have no idea.
On line I saw at least one China site that had much larger outputs available.  The prices were modest. FWIW.
Regards,
Perrier