I think I said it all in the title. I have RS Discone on a 5 foot mast on the roof my house and I hear everything in my area just fine. I have some mountains within 5-10 miles of me that as far as I know are not blocking any signals because they have antennas mounted on one of the peaks. I was given an extra antenna mast and I could get one more if needed, but do you think 5 or 10 extra feet would make a difference in what I can hear. I listen to AIR, police and fire on VHF and UHF and I have not tried to listen to anyone greater than 30 miles from me. Finally, last question, during a storm the grounding wire I had came loose from the roof section so before I climb up to the roof to fix the wire I wanted to get your feedback on adding another mast.