oaktree said:we signed off for 15 minutes at 7:00 AM to allow some station out West to sign on.
Fascinating history, but why sign off to allow a station out West to sign on? The dominate Class A was KSL with its 50-gallons. I understand about "critical hours" but don't understand why WJJD would have to sign off for 15 minutes for a sign on a time zone away. A pattern change only takes seconds and doesn't affect much after sunrise in your time zone. Just curious. I worked at a station with a half dozen pattern changes a day, but never signed off. I remember power changes, too, but haven't heard of this.
A half dozen pattern changes a day? I don't think so. A Class B AM located west of the primary co-channel Class A on one of the few channels on which the primary class A operates at night with its daytime facilities until local sunset at the secondary co-channel Class A (examples: 1530, 1560) could have a lot of pattern/power changes over course of 24 hours, but SIX per day? I dunno. I think the worst scenario would be the following:
Class B sunrise
Two hours after Class B sunrise
Two hours before Class B sunset
Class B sunset
Secondary Class A sunset
I believe that there may be a 1560 station in KY with a schedule that complicated, but that's still only five pattern changes per 24 hour period. WQEW is the primary class A on 1560; KNZR is the secondary Class A. The Class B in question is the KY station. Maybe the extension of the end of Daylight Saving time into early November (went into effect in 2007, I believe) could add another early-morning pattern change to this schedule. If so, I believe it would apply only during the first few days of November. I must confess that haven't figured that out;>( Hasn't the FCC made an exception and allowed October sunrise times to be used from November 1 until the end of DST?