On Oct 24, 8:14*am, "Jon Slaughter" wrote:
It's because the paths are not the same. Think of a silvered mirror. It can
transmit light much easier in one direction than the other. Take both
outside and see if it has the same problem. (extremely doubtful because the
path's is virtually identical)

Did you design the receive software?
Or did buy the receiver "off the shelve"?

Perhaps there is a problem
with the receivers and how they are
receiving the data.