For many stations operating on their post-transition DTV channel specified in the final DTV Table of Allotments, they have only one action to take to complete their DTV transition at midnight Feb. 17, 2009: Switch off the analog transmitter.
For the rest, the transition will be more complicated, and in some cases extremely complicated. The FCC Report and Order in Third Periodic Review of the DTV Transition released New Year’s Eve provides guidelines for these stations and also sets firm deadlines. The FCC did provide some relief for stations that have complicated antenna swaps and other such actions before providing their certified coverage. However, stations that take advantage of that relief and operate their facilities with less than full coverage will be obligated to make repeated announcements that they are operating at less than full coverage. In these announcements, they are required to explain when full coverage will be restored, and also what actions are available to viewers impacted by the reduced coverage.
There are too many scenarios to present in this RF Report, but here are some steps stations should take now to make sure they are prepared for Feb. 17, 2009. The first is to download Appendix D of the Report and Order. If your station is on this list, other than filing the required FCC reports, no further action is needed (unless you wish to maximize coverage) until the analog transmitter is turned off for good.
If you’re not on this list, the FCC is going to require reports on your station’s progress in preparing for the transition. It will then post these reports on the FCC Web site for the public to see. All stations are required to complete FCC Form 387, either to confirm their Appendix D status or list the current status and next steps in their DTV transition plans. While I haven’t seen Form 387 on the FCC web site, a copy of the questions is in the Report and Order. This form must be filed by Feb. 18, 2008.
As described in earlier RF Reports, many stations planning a return to their VHF channels found that the antenna patterns in the Final Table of Allotments didn’t match their current analog antennas, and in some cases would be difficult if not impossible to produce. The FCC is making it easier for stations switching DTV service to their existing VHF antennas and avoiding the disruption and off-air time that would be needed to replace antennas or the significant reduction in coverage area to stay within the pattern in the Final Table of Allotments. These stations are being allowed to extend their contours by up to five miles in any direction, if needed, to avoid coverage loss. However, extensions will not be allowed if there’s an increase in interference by more than 0.5 percent to any other post-transition DTV station. Interference guidelines are somewhat relaxed for interference to analog TV stations.
While the Commission set strict limits on interference and requirements for coverage, it indicated it was willing to be flexible when stations faced special circumstances. It also gave Media Bureau staff the ability to make these decisions without full Commission approval, which should speed the process. If your station needs to take advantage of this flexibility, I recommend doing the engineering studies and filing the application for modified post-transition facilities as soon as possible.
Some stations planning to remain on their pre-transition DTV channel have not built out their construction permits for their certified facilities. The FCC set May 18, 2008 as the deadline for completing this construction.
Stations that will use their pre-transition DTV channel after the transition, but do not have a license or construction permit matching their post-transition DTV Table of Allotments facilities, must complete construction by Aug. 18, 2008. Note that in some cases the licensed facilities may closely match the DTV Table of Allotments facilities in coverage, but operate at a different height and power level. It is also possible that pre-transition interference limits have prevented a station from fully matching its analog coverage, especially low-VHF analog coverage. A small power increase, combined with the five-mile allowance on contour extension, may be all that’s needed to meet the final DTV Table of Allotments coverage, even if the heights and power levels differ slightly. In any event, if a station can’t match the certified DTV Table of Allotments coverage, it should file an application requesting a change to the certified coverage.
Stations that weren’t able to maximize their coverage pre-transition due to interference to analog stations have found themselves in a difficult position. The FCC did not allow them to increase power beyond currently authorized levels, even if their facilities were significantly less than others in the market, unless they could find another channel. These stations will finally have a chance to file for maximized facilities on Aug. 17, 2008. The 0.5 percent new interference criteria will apply to these applications.
If your station is operating at significantly lower power than other DTV stations in the same band in your market, it would be worth investigating maximization. While the FCC service contour may show full replication of your analog service area on the lower power DTV facility, this is based on the FCC/ATSC planning factors that require an outside antenna 30 feet high. If most other stations in your market are operating at power levels providing reception on simple indoor antennas, there is no reason for a viewer to install an outside antenna and mast. When they scan for DTV channels on their new set-top box or DTV set, your DTV signal may not even appear and when analog TV is shut down, viewers will no longer see your station.
The next date to be concerned with is Oct. 20, 2008. The FCC expects stations to have completed construction of their final DTV facilities by this date. If construction hasn’t been completed, FCC Form 387 needs to be updated with details on the status of construction and the FCC may request additional information on construction status.
The final date, of course, is Feb. 17, 2009. While ideally all stations would be able to switch to their final DTV facilities at midnight, a variety of circumstances could prevent this. The FCC will consider applications for special temporary authority to remain on a pre-transition in-core channel temporarily before transitioning to the final channel. This could benefit stations that need to remove analog antennas before installing new DTV antennas, or that intend to convert freed-up analog equipment for use on the final DTV channel.
This is a quick summary of a 154-page document. If your station is not listed in Appendix D of the Report and Order I strongly encourage you to review the Report and Order in Third Periodic Review of the DTV transition to see all the options available.
Doug Lung is one of America's foremost authorities on broadcast RF technology. He has been with NBC since 1985 and is currently vice president of broadcast technology for NBC/Telemundo stations.
Future US's leading brands bring the most important, up-to-date information right to your inbox
Thank you for signing up to TV Tech. You will receive a verification email shortly.
There was a problem. Please refresh the page and try again.