Question

What is the difference between roof mounted and glass mounted antennas?

Answer 1

There is a difference of 3 dB between glass mounted and rood mounted antennas.
 
Glass mounted antenna
 
# This antenna is mounted on glass.
 
# There is no need to drill a hole to mount this antenna.

# The antenna is positioned lower than the roof mounted antenna.       
 
Roof mounted antenna
 
# This antenna is mounted on a roof.
 
# A hole must be drilled to mount this antenna.

# The antenna is positioned higher than the glass mounted antenna.