[Elecraft] OT - anyone have experience with effects of metal roofs on antenna performace?

[David Cutter]

A 4 square can be badly affected by metal (towers, masts, metal roofs).  The 
gain is similar but it loses front to back ratio in the affected direction.

David
G3UNA
>
You forgot the Gain. Forexample you can loose  2 - 3 dB gain on an
antenna due to interaction with another antenna or "object" and see
no nothing on the SWR you measure down in the shack. Then you think
everything is fine a perfect, well maybe it´s good since what you don´t
know you don´t worry about.
/SM2EKM