Quote:
Originally Posted by Electron
... The main reason for grounding the coax and even the antenna in the attic is to direct interference to ground and have better reception.
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To be fair, I'm not certain if your statement covers both attic and outdoor installations. Because the OP specifically inquired about outdoor installations, my comments below are predicated on the assumption that your statement is referring to both attic and outdoor situations. Please correct me if my assumption is incorrect.
I firmly believe the main reason for grounding is for protection of people and property regardless of were the antenna is mounted.
If there is reduction of interference, I'm very pleased. But interference reduction is of secondary importance to me, and I suspect the OP and others who have had valuable equipment damaged.
As a side bar discussion in a separate thread, I would welcome an explanation of how grounding the coax shield can reduce the amount of on-channel interference received by the antenna which is then coupled to the center conductor and inner shield surface in differential mode (which is what the tuner input is connected to). A correctly installed ground connection that provides a low resistance/impedance path to ground at DC and power-line frequency can not be expected to do the same at VHF and UHF frequencies unless carefully engineered to do so, and then it will only provide a low impedance at one or a few specific VHF or UHF frequencies unless the length or the ground conductor is extremely short, a fraction of a wave-length. The same physics that govern antenna element length design, apply to ground conductors. Inductive reactance, distributed capacitance and resistance all increases with the length of a conductor when the cross section is constant.