I was thinking abt just mounting antenna on side of
something heavy such as concrete block and SETTING it
on top of roof.

Uh! Something heavy on the roof. Danger! I remember my parent's sat
dish stopped working after a storm. My father and I went up under the
roof and found out that the tube holding it was only fixed with two
hose clamps. Turned the tube until reception quality was okay again,
fixed the clamps and went down.

If there is some tube at the outside of your house you can fix such a
tube with a dish mounted on top at it. Or if there is some gap
somewhere in the roof put the tube through it. Or if you can drill a
few holes to the wall mount it at the outside. Or... - be creative!

virtuPIC
--
Airspace V - international hangar flying!
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