To coordinate or not to coordinate, that is the question . . . and when to coordinate – that’s another question. Oh yeah, when to include proof of coordination – let’s not forget that one, too.

The Wireless Bureau has issued a declaratory ruling clarifying when prior coordination is required for Broadcast Auxiliary Service (BAS) microwave applications above 2110 MHz – facilities generally used by TV stations for studio-transmitter links or relays linking other locations. The coordination requirement is based on whether a change could affect other licensees and not whether the change is “major” or “minor.”

New BAS fixed microwave links and major changes in existing links must go through a formal coordination process, where existing licensees and applicants who may be affected are notified and given an opportunity to protest, before a license application is filed with the FCC.  

Coordination is also required for “major” changes, which are changes in:

  • location of more than five seconds of latitude or longitude;
  • area of operation;
  • frequency tolerance; transmission bandwidth;
  • emission type (including conversion from analog to digital);
  • EIRP (power), if increased by more than three decibels;
  • antenna beamwidth or polarization; or
  • antenna height, if increased by more than three meters.

In other words, if a change affects the extent to which your signal can cause interference to others, the change is “major”, and you have to coordinate before filing for a license. Several engineering firms offer coordination services.

On the other hand, minor changes – which have less impact than the major change categories noted above – may be implemented as a matter of right. However, if there is any change in operating parameters, the FCC must be notified by a license application to be filed within 30 days after the change is made. 

Disagreement apparently evolved in the engineering community recently as to whether coordination must be completed prior to implementing a minor change. The FCC’s answer is “yes” – IF the proposed change “could affect or be affected by” anyone else’s facilities, in which case you must coordinate first, and then implement your minor change and file your license application.   The coordination process usually takes at least 30 days.

The ruling is important because the same Form 601 is used for both major and minor changes. Written evidence of prior coordination must be attached to an application for a new station or major change, but not a minor change application. Nevertheless, the FCC says, the fact that you do not have to file a prior coordination notice for a minor change does not mean that you do not have to do the coordination if any other station or earlier application might be affected.

The FCC really means that prior coordination is required if a major or minor change could adversely affect anyone else. There are some changes that might help others by allowing them to expand, but prior coordination is not required if the effect cannot be adverse. Examples include deleting a path, deleting a frequency, reducing power, or reducing occupied bandwidth, which could allow another station to improve its facilities but cannot hurt anyone else. Even in those cases, however, a license application must be filed within 30 days after the change is made, so that the FCC can update the database used by coordinators.

The formal coordination process, described in Section 101.103(d) of the FCC’s Rules, is not required for fixed or mobile stations below 2110 MHz (including “2 GHz” ENG systems), mobile stations in higher bands, or short-term operation of 30 days or less under Section 74.24. In those situations, informal coordination is required with all licensees in the area. “Informal coordination” entails contacting a local frequency coordinating committee if one exists, or otherwise contacting anyone you can find who might be affected by your proposed operation.

So now we know that prior coordination is needed for almost any change except cutting back or discontinuing an operation. But how can we be sure? The FCC admits that “there may be other minor modifications that may not require prior coordination”, but a “comprehensive list” is impossible to make, because whether or not a change would affect or be affected by other facilities must be decided “on a case-by-case basis”. When you’re planning a change, it’s a good idea to chat early on with your engineer, so that coordination gets taken care of and does not turn into an obstacle that delays project implementation.

While the FCC’s ruling appears directed at only TV auxiliary licenses, Section 74.502(d) of the FCC’s Rules requires that the Section 101.103(d) coordination procedure by used for applications for radio studio-transmitter links in the 950 MHz band.  Presumably then, the same interpretations can be applied to radio links.