ABSTRACT
The Program Identification (PI) code is the backbone of all Radio Data System features. In the case where several full-power stations carry identical programming, it is essential that the same PI code be used on all stations. Consumer receivers use the PI code to verify that they are tuning to the same audio program. The reason that these special PI codes are used is that many large networks have stations that will break away from the main program at different times of the day to provide local programs. The second nibble of the regional PI codes tells the receiver how the tuned station is linked to a larger network. The use of the PI code along with the extended country code can allow the receiver to self-configure some of the following parameters: AM and FM band edges and tuning steps, FM stereo de-emphasis.
