I still do those stations, but I like to know in advance if they have a Christian format. Recently, I've begun to look for a station's call letters in the National Religious Broadcasters' Directory of Religious Media. Many of my appearances have been extended for an extra hour or so. It all depends on audience response and whether another guest is scheduled to follow you. You want to be sure you have enough material on hand for a longer show.
Most programs are live, and because of callers, are the most interesting.
Occasionally, the host will tape your interview for a later airing. Write down the producer's name and phone number. If you have to cancel, call as far in advance as you can. When setting the date and time, be sure you understand what time zone the show is in. Don't forget to write down all this information in your appointment book.