Originally Posted by coyoteaz
Pacific primetime runs 8-11, Arizona runs 7-10. Even though the clocks in Arizona match the clocks in California when California is on DST, Arizona TV stations are still running primetime an hour earlier and thus can't use the Pacific feed.
You are quite correct; I misspoke, and I apologize for that. It is during Standard time (winter) when the schedules for the west coast and AZ are in sync, even if the clocks are an hour apart. But the reason for not using that feed then is partly based on the same issue of regionalized spot sales. Advertisers want a more targeted demographic, although I am not sure what the perceived differences might be between viewers on different sides of the Rockies.
Also slipping my mind was another reason why it makes more sense for AZ stations to use server delays for prime, which is that the codes to control the branding (which consists of the corner bug and the top-of-hour legal ID) are in the bitstream as it comes from FOX. The bugs themselves are generated locally from those codes as part of the ROSA MPEG splicer system.
The problem was that even though AZ stations used to demux out a separate program stream from the multiple program transport stream, the branding codes were not always specific to the feeds.
Some FOX stations on the west coast for whatever reason carry the Saturday late night stuff at 10 PM AZ time for part of the year, while KSAZ carries news at that time. I think this is for west coast stations that don't mount an 11 PM newscast on Saturdays.
Because they claimed that "the script can't be changed" this would mean that KSAZ would get the branding for FOX late night inserted over their local news, even though KSAZ did not carry that programming until 11 PM AZ time, an hour later, which meant bugs on KSAZ's air over the wrong programming every Saturday night for half the year. It also affected stations that opted to carry an earlier feed of Fox News Sunday
It would appear to be simple matter to fix this by muxing in separate code sets for each program stream, but FOX never could seem to find the handle. I think it might have been one of those embarrassing situations where a master plan has an unfixable flaw that is only noticed once the system is deployed. The auto industry deals with this with recalls. The broadcast industry is a 24/7/365 proposition, so fixing such flaws would be the equivalent of replacing your faulty fan belt while you are still driving down the freeway at 75.
There was never a clear explanation why FOX could not fix this, or even why it was problematic in the first place, but their solution was to place stream servers for delay at the stations that did not carry programming in step with the rest of the stations. That allowed the stations to delay the programming and the codes equally, putting everything back in sync.
Wacky, but true.