[TowerTalk] RF Surge Suppressor at Base of Tower or Shack SPG or Both ?

[Michael Tope]

Jim, et al:

What about control cables coming down the tower? I just skimmed through 
the first edition of Ward's grounding book. It recommends bonding the 
coax shields to the tower, but doesn't say anything about control 
cables. Typically there is a least one rotator control cable in the mix 
and oftentimes additional control cables for array switches and multiple 
Tic ring rotators on larger more sophisticated installations. That seems 
like an inconsistency, no?

73, Mike W4EF...........

On 10/12/2021 2:28 PM, Jim Brown wrote:
> On 10/12/2021 11:14 AM, Shawn Donley wrote:
>> Where should the coax surge suppressors go?  At the base of the tower 
>> or at the shack entry box or both?
>
> Where antennas are bonded to all the bonded grounds, where they enter 
> the shack. They protect the rig(s) two ways. First, by bonding the 
> coax shield, and second by shorting the center conductor to that ground.
>
> The coax shield should be bonded to the tower at top and bottom, but 
> an arrestor at the tower is a waste of money.
>
> Remembering that lightning is an RF event, not a DC event, a 130 ft 
> long bonding wire looks like an inductor, and is essentially a waste 
> of copper. It's only required if you have mains power at the tower, in 
> which case it must be run with the power conductors (as with Romex, or 
> in conduit).
>
> The N0AX book is a great reference, to which I contributed.
>
> 73, Jim K9YC