In message , Jeff Liebermann
writes
On Fri, 07 Sep 2012 19:35:42 +0200, Helmut Wabnig [email protected] ---
-.dotat wrote:

Rent a room directly under the roof.
w.

Or, get an outdoor or marine AM/FM receiver and mount it on the roof
in a weatherproof NEMA box.
http://www.ticcorp.com/outdoor_amplifiers_amp10pic.htm
CAT5 should be sufficient to run the audio and DC power down the pipe
to the server cave.

I think a Google on 'active antenna' might give you a lot more general
information. Start he
http://en.wikipedia.org/wiki/Active_antenna

They typically untuned (and hence fairly wideband).

An active antenna often consists of a short whip antenna, which
functions as a high-impedance RF voltage probe. This is connected to the
input of an amplifier which has a very high input impedance. The
amplifier provides gain, and also converts the high impedance of the
whip to a low impedance, which is suitable for connecting to 50 or 75
ohm coax feeder.

Of course, the amplifier has to be powered, and typically this is
provided by a DC power unit located at the receiver end, which sends the
necessary power back up the coax.

Note that one thing an active antenna must do is not to be overloaded by
strong signals (which can be a problem if you have a local transmitter
or two in your area).

But as I say, have a Google, and see what information it brings you.
--
Ian