Quitting Cable: Day 52 – Staying [Common] Grounded

Posted under A Geek Dad's Life, Blog Posts, Quitting Cable

Flash-Crack-BOOOOOM!!! Lightning and thunder woke us up this weekend during the first major Spring storm, and [boy] was it striking close to our house.  My first thought was of the new over-the-air antenna sitting on top of my garage, not properly grounded.  Doh.  This first storm was a not-so-gentle wakeup call. 

Lightning is a mysterious phenomenon.  It can strike a person directly without killing, and it can strike the ground killing everyone nearby.  More frightening to us technophiles than personal injury, lightning can really ruin your day by causing your expensive electronics to release the magic blue smoke required to make the gadgets function.  Sometimes the devices go out with a whimper or barely audible *pop*, and sometimes the devices go out with a flash and a bang.

When we subscribed to cable television from the utility pole, the cable was grounded at the point which it connected to the house using a ‘ground block.’   When I disconnected the CableCo’s cable and installed our new off-air antenna in February, I was really still in the “let’s see if this will even work” phase of the project.   Also, lightning was not a major concern in February, so I did not think about grounding it.  I changed my tune when I saw/heard that lightning/thunder!

My first instinct was to go buy a new grounding rod and some wire at the local Home Depot, but I remembered that “ground loops” can cause problems with RF signals.  I spent 2 hours researching the topic on various sites and determined that I should NOT mess around with a second grounding rod.  Using two grounding rods connected to the same house at different points can create dangerous ‘ground differentials.’  It can also be very expensive to bond the two grounding rods together due to the raw material cost of heavy gauge (#4) copper conductors and the complexity of burying the conductor at the proper depth.  According to every expert on the subject, your house should have a single point of common ground, and everything should be tied to that single point. 

So, I ran the antenna feed to the original grounding block from the original cable connection, and I ran a new ground wire from the antenna mast to the ground point on the house provided by the power utility company.  Whew.  We’re safe again.  Or at least as safe as we can be when it comes to lightning.