Thanks,
Ideally you would connect a #10 ga. copper wire (larger diameter wire is fine) to the mast. Home improvement stores carry a variety of electrical ground clamps that would serve the purpose. The other end of the ground wire would connect to the electrical service ground. Ideally, the wire would be as short as practical and run outside the building structure. Sharp bends should be avoided.
The coax shield should be grounded before entering the building. The preferred method would be to run the coax from the antenna down to a location close to the electrical service ground. There, install a coax ground block, and run a short length of #10 ga, copper wire to the electrical service ground.
If you elect to add a ground rod for what ever reason, it needs to be connected to the existing electrical service ground system with a #6 ga. copper wire (or larger diameter).
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