Clark Details Digital AM Night Theory

Broadcast engineering consultant Glen Clark declared that IBOC’s AM nighttime bugaboo isn’t so bad, that it’s “not time to drink Kool-Aid” anyway. At a digital broadcast engineering session for NAB2003, Clark detailed his theory submitted earlier to the FCC that the majority of AMs could go IBOC now without causing undue interference to either their host analog signal or their neighbors. Of the roughly 2,800 AMs in the U.S., Clark said 1,881 could go digital at night now, another 873 could go digital with a reduced (digital) power level and 95 could not go digital without causing potential interference to neighbors.
The AM nighttime skywave versus groundwave issue is shaping up to be a battle between group owners who own historically-protected Clear Channel stations that operate using skywaves at night, and group owners whose stations operate at night using groundwaves. One radio group engineer told RW Online there’s no easy way to solve the problem.
Clear Channel’s Jeff Littlejohn wanted to dispel the notion some may hold that skywave listening is unimportant. He said skywave-listeners make up approximately 10% of such a station’s night-time audience and such listening is quantifiable by Arbitron.