Volunteers Providing Emergency Communications for Multnomah County, Oregon

From the EC’s Desk

Grounds and Grounding

There has been a lot of activity in the station building front in MCARES over the past few months. As I receive stories and reports I am greatly encouraged by everyone’s willingness to jump in and build a better radio station. One of the main topics of concern folks have when installing a new radio station is proper grounding. There is considerable confusion and strong feelings over this topic. I cannot hope to clarify the technical aspects of station bonding and grounding in a newsletter setting, but I do want to make sure that everyone is looking in the right places and asking the right questions when they consider their station grounds.

There has been a lot of activity in the station building front in MCARES over the past few months. As I receive stories and reports I am greatly encouraged by everyone’s willingness to jump in and build a better radio station. One of the main topics of concern folks have when installing a new radio station is proper grounding. There is considerable confusion and strong feelings over this topic. I cannot hope to clarify the technical aspects of station bonding and grounding in a newsletter setting, but I do want to make sure that everyone is looking in the right places and asking the right questions when they consider their station grounds.

First off, the best way to get the right information is to research the situation oneself from the appropriate resources! MCARES is adamant that the ARRL technical publications are the best place to find information that has been vetted by competent engineers and will lead to safe and effective station construction. The two best publications are Grounding and Bonding for Radio Amateur and The ARRL Handbook. Additionally, The ARRL Antenna Book for Radio Communications has very good in­-depth information regarding RF grounds and their effects on radiated signal.

When one begins their shack, consider the four types of grounding/bonding that are part of proper station design. These are:

  • Electrical Safety Bonding
    • The ground that provides the path for over­current protection and provides chassis shock protection.
    • This is the third prong / green wire in your house distribution
  • RF Ground
    • It is important to keep the shack equipment at the same reference potential to avoid current flows or potential differences that can affect the operation of modern equipment.
  • Chassis Ground
    • These are the connections we think of for grounding inside the shack, the individual chassis connections to a great, fat ground bar that makes its way to a good earth ground.
    • Bonding of equipment to prevent RF flow between them can be difficult, so make sure your ground strap setup is as clean and short as possible.
  • Lightning Dissipation
    • The design of these systems can be complicated; make sure to review your desired results before implementing lightning protection. Again, review the appropriate technical references when you go to set up your operating station, and stay away from QRZ and eHam forums; you’ll find too much time there will make you want to give up on grounding altogether.