Tom Ring wrote:
"Motorola 900 MHz Canopys are advertised as "non line of sight"... so
you may get more mileage than you`d expect when running at the
relatively low frequency."

It`s true that radio does not always take a direct path. Part of ham
radio fun is in anomalous propagation. It`s also true that the higher
the frequency, the smaller the obstruction that can block propagation.

900 MHz is more reliable than frequencies in the GHz. A point to
multipoint system may require more reliability than a single point to
point system, and more reliability than: "Can You believe it? I`ve
contacted DX!" I`ve engineered and installed several 900 MHz systems
which proved to provide, with their path clearances and fade margins,
24-7 reliability of very nearly 100%.

Line of sight is defined as: "The distance to the horizon from an
elevated point, including the effects of atmospheric refraction."
Another definition is: "The propagation characteristic of microwave
radio."

900 MHz is on the border between UHF and microwaves. It shares some of
the characteristics of both.

Best regards, Richard Harrison, KB5WZI