Mmmmm... are you referring to your antenna as your lightning rod? :twisted: Well, it's supposed to be the antenna support structure and all appurtenances. That's generally the tower and antenna. In the land mobile industry it's not uncommon for an entity that doesn't have any other restrictions to put up a 180 ft. tower with a 20 ft. antenna on top of that. A 5 (fiberglass - like a PD-220) or 6 (collinear dipoles - like a DB-224) dBd VHF antennas or 10 dBd UHF antennas (PD-455/DB-420) are generally 20 ft. long, excluding the mounting stub.
A wise site manager or RF telecommunications engineer will figure out the area he or she needs to cover, then put the antenna off the side of the tower. Then, put corona dissipation arrays on top, especially in Florida. The tower will take the hit and conduct the lightning impulse to the ground. In that case, the tower can go up to 200 ft with no additional topside appurtenances. Here's an article on
static wicks, like you'd see on an aircraft.
It is not wise to put a fiberglass radome antenna up top. The instantaneous bend moments from wind will, over time, break the welds between the elements inside the antenna. You will then have arcing in the antenna under full duplex conditions and will have one or two of two conditions: noise/"static" artifact, and signal levels that can be observed to be multiple levels in RSSI or on a spectrum analyzer. A fiberglass radome antenna is for side mounting along with lateral stabilization standoff on the top of the antenna!
I probably should not have to say this, but I will put it out there, anyway. If you do put up a tower, you are wasting your money if you don't run hardline (7/8" for UHF and at least 1/2" for VHF for a 180 ft. run) and a professional grade antenna. I've seen a lot of people put up towers and top them off with a Ringo or AEA Isopole and 300 ft. of coiled 9913 coax. First windstorm and they have a stub. Lightning strike and the thing looks like an exploded cartoon cigar with a coat hanger sticking out. You can't slap them, it's not legal anymore, and you get in trouble. Do it right the first time and follow the
NEC and
R56 grounding and
bonding standards.
Wind loading is important to you, especially if your tower is within the
fall zone for your house (or, like me years ago, my neighbor's swimming pool). That also goes for professionals. Don't crust it up like it's a Christmas tree.
And, finally, BE SAFE. Rigging a tower is not a beginner's job and you don't get proficient by watching a Youtube video. Everyone is a
safety man (or woman), everyone needs PPE.
If I sound pedantic, it's only because I don't want you or someone else who comes across this in the future to
die from taking a shortcut. That's a permanent condition. Have fun and best of luck with however your project turns out.