"Robert11" wrote in message
. ..
Hello,

For the scanner frequencies in general from approx.140 MHz to 1 GHz, is
propagation truly
line-of-site "totally", or is there bending of the signals by some
atmospheric layer possible at various times ?

Any around 156 MHz fm in particular ?

Is there ever any "ducting" ?

Thanks,
B.

yes there is normally some bending and refraction around hills and buildings
so it is not totally line of sight. generally the higher the frequency the
less bending and the better view of the antenna you need. and yes 150mhz
does duct very nicely at times.