[Antennas] Metal Roofs in Near Vicinity of Antennas

Fri Nov 5 11:17:51 EST 2004

I plan to build a small barn, 24' by 24' next year for shop area for 
car and motorcycle repair and restoration and for wood working. The 
upper loft, about 15' by 20' would be for my amateur radio shack and an 
office for consulting work. I plan to install 40' or 50' of Rohn 25 
tower near the front or back of the barn near the peak so that I can 
use an eave mount and eliminate guy wires.
I would like to use a metal roof on the barn but I am concerned whether 
dipoles and a three element beam (20, 15 and 10) mounted at the top of 
the tower would be affected by the metal roof. The peak of the barn 
will be somewhere between 19' and 22' from the ground so I would have 
about 20 feet separation if I us 40 ' of tower, 30' if I use 50 ' of 
tower.
It seems that one option would be to use a vertical so that the roof 
functioned as my ground radial. If install all wiring in metal conduit 
I would have minimal noise from electrical equipment in the barn to be 
picked up by the vertical.
Any ideas or cautions?
Don Williams, kd6uvt; with interests in gardening, genealogy, ham 
radio, motorcycling and mountain climbing. What do you want to be in 
life, a spectator or a participant? kd6uvt at arrl.net