Someone needs to do a link calculation, IMO. From what I remember, the numbers just didn't work for the amateur. As I recall that the transmitter was a pulsed laser of several watts at least, the Tx was a 24" or larger telescope, the Rx was similar and they only got a few photons back, if they were lucky. The Rx was a range gated PMT. This is not really practical for amateurs. -John