The website Slate has an interesting piece on ‘The Broadcast Clock: The Diagram That Rules Public Radio’.
At NPR’s studios in Washington , D.C. , there are clocks everywhere. Big red digital clocks, huge round analog clocks.
Slate notes each show also has a virtual “clock,” a set template, from which the show almost never varies. Every show that broadcasts—or aspires to broadcast—in the public radio system has a clock.
The article also shows the clock for NPR’s extremely popular ‘All Things Considered’ show which airs afternoon.