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Radio Data System (RDS)

All uplevel audio systems are equipped with technology known as the Radio Data System (RDS). RDS is a system that sends data along with the audio of the FM station you are currently tuned to. RDS is a standard that defines how a FM broadcast station may send digital data along with the audio program. Think of it as a one way wireless modem, allowing the broadcaster to send information about his program to your receiver.

RDS data is carried in what is known as a "subcarrier". A subcarrier is a frequency that the FM broadcaster is authorized to use to send data or other audio programs that are not audible in the main audio program. RDS information can be used to display program information and to control the radio.

To receive the RDS signal, all that is needed is an FM receiver with a RDS circuit. A special integrated circuit capable of dealing with the RDS signal is in the RDS circuit and passes it along to the receiver's microprocessor where it is decoded and acted upon.

RDS Basic Information
RDS basic information:
^ RDS functions are provided in the FM broadcast band only.
^ RDS functions will only work with FM broadcast stations that are broadcasting RDS data.
^ Not all FM Broadcast stations broadcast RDS data or offer all of the RDS services.
^ RDS functions may not work properly when reception is weak, reception is of poor quality, or RDS is not implemented properly by the FM Broadcaster.

In some cases, a radio station broadcasting incorrect information may cause the RDS features of the radio to appear to work improperly.

Broadcast RDS information can be used in a variety of ways by the receiver and listener, but basically falls into two categories: Display and Control.

Displaying Program Information
RDS displays textual information such as:
^ The name of the station.
^ The type of program.
^ General information such as artist and song title, call in phone numbers, etc.

Turning RDS on
The RDS select button is located in the lower right hand corner of the radio face. Press the RDS select button to use the alternate RDS functions on the six preset buttons. After pressing the RDS select button, press the RDS (preset 1) button to turn RDS on or off. When tuned to a non-RDS station, your radio will display frequency information as you would normally expect. When tuned to an RDS station, your radio will change from displaying the frequency of the FM station to displaying the call letters of the station or display the nickname of the station. This feature is known as the Program Service Name.

Using the RDS Traffic Feature
Some RDS broadcasters may carry traffic information programming to inform you of current traffic conditions in your listening area and is indicated by the TP icon in the radio display. RDS enables the broadcaster to get this information to you even when you are listening to a tape or compact disc. This feature can be enabled or disabled by the listener. Press the RDS select button, followed by the TA (preset 2) button to find a station that claims to carry traffic information. You may do this even when playing a cassette tape or compact disc. This action will operate in the background without interrupting the current playback. If the radio is not currently tuned to an RDS traffic station, the radio will immediately SEEK an RDS traffic station. If the radio finds an RDS traffic station, the TP icon will appear in the radio display. If the radio cannot find an RDS traffic station after searching through the entire FM band, the radio will display "NONE FOUND".

Viewing Messages
When MSG appears on the radio display, a new message is available for viewing. These messages are from the RDS broadcaster and may be general information such as artist and song title. To view the text message, press the RDS select button, followed by the MSG (preset 3) button. If the whole message does not appear on the display, parts of the message will appear every three seconds until the message is completed. To view the message faster, press the MSG button again.

Using Program Type Presets
The radio has the ability to use RDS data to find stations according to Program Type (PTY). When in PTY mode the preset buttons are now PTY presets instead of frequency presets. To turn PTY mode on or off, press the RDS SELECT button, followed by the PTY (Preset 4) button.

Selecting a PTY
The preset 5 & 6 buttons can be used to scroll through the list of available Program Types (PTY) that can be used to find RDS broadcasts. Press the RDS SELECT button, followed by the preset 5 or 6 button to scroll through the available program types. The radio will show the PTY icon to indicate that it is in PTY mode. When the desired PTY is shown on the display, press the TUNE/SEEK button. The radio will search for an RDS broadcaster that is carrying the PTY you selected. If the TA icon is displayed while performing a PTY search, the radio will look for an RDS broadcaster of both the selected PTY and traffic information. If the radio cannot find the desired PTY, the radio will display NONE FOUND and return to the station you were last listening to.

RDS Clock Time
Broadcasters can choose to send clock time information in the RDS data. This information can be used to update the clock time on the radio. RDS clock time is broadcasted once a minute. To set the clock press the RDS SELECT button. Then press and hold either the HR or MN button. If the broadcaster is sending clock time data the display should show "STATION TIME IS xx:xx". If the time is acceptable, simply continue to press and hold the HR or MN button until the display shows "TIME UPDATED".

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