Non-permanent method to mount TV antenna?

I rent one half of a small duplex that kind of sets in
a "bowl" as far as good HD TV signal reception.

I'm def going to have to use an outdoor antenna to get
off air digital TV channels. Thing is I'm looking for a
non-perm method of mounting a smallish TV antenna up
high..... roof or something.  No drilling or mounting
wanted if possible

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

Any other ideas out there?