Channel Changes Vex DTV Transition
I was in Los Angeles on June 12 when two of our stations switched from normal programming to nightlight status. A third station—with an out-of-core analog channel—shut off its 14-year-old Comark transmitter for the last time.
Overall, from what I saw, the analog shutdown went very well for stations that weren't changing channels. I think most broadcasters would agree that the four month extension and extensive broadcaster and FCC education efforts paid off.
While stations that were able to stay on their pre-transition channels had few problems, those that changed channels, especially moving from UHF to VHF, were not as lucky.
One problem was that some DTV converter boxes and DTV receivers didn’t update RF channel information for stations that had previously been scanned. For example, if the boxes had stored Channel 67 as the RF channel for WCAU, the only way viewers with the affected converter boxes could see the station after it moved to channel 34 was to punch in 34.1. Using 10.1 wouldn't work, even after a channel scan. The FCC issued a Consumer Alert advising viewers to “double rescan” to solve this problem.
Double rescanning involves removing the antenna from the DTV converter box or DTV set, doing a scan, reconnecting the antenna, and doing a second scan. The first scan, without the antenna, clears all stations from the memory. The second scan restores them, with the proper RF channels. The Consumer Alert also recommended viewers do additional scans after relocating their antennas.
The move from DTV on UHF channels to DTV on VHF channels caused major difficulties and I’ll cover it in detail in another article this week.
With a few exceptions, it appears most of the problems occurred in markets where all stations used UHF DTV channels until June 12. In San Francisco, where the NBC station KNTV transmits on DTV channel 12, viewers had an opportunity to learn before the transition that they needed DTV antennas that would receive VHF as well as UHF. When ABC station KGO-TV went back to its VHF analog channel for DTV, viewers that had been watching NBC on KNTV were ready for it. That wasn't the case in New York, Los Angeles, Washington D.C., Philadelphia and other markets where there were no VHF DTV stations on air prior to June 12.
Some viewers weren't ready for the transition at all, while others had converter boxes, but didn't know how to use them. Gary Sgrignoli's Updated FAQs and Answers for the DTV Transition is a good reference for station personnel helping viewers with reception problems.
The good news for broadcasters is that these viewers—once they got their DTV sets or converter boxes working—were very happy with the excellent picture and expanded choice of channels. A director of technology that I spoke with this week summed it up well.
He said that while talking people through the setup of their converter box or DTV set could be frustrating, hearing their reaction after seeing their first DTV picture once they had it working made it all worthwhile.
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