— 10 —
AF
List of Alternative Frequencies:
A broadcasting network, or a pri-
vate broadcaster using low-power rebroadcast transmitters
(‘translators’) to fill holes in his coverage area, can include a list
of all frequencies where the identical program can be heard at
that very time (synchronously). Upscale RDS receivers con-
stantly search for the best signal that carries the very same
program. When a stronger signal is found, the radio re-tunes
to it with no audible interruption. The principal utility of this
RDS function is with European radio networks and US stations
with translators. The 730 can hold as many as 25 Alternative
Frequencies.
CT
Clock Time and Date:
The Radio Data System is capable of set-
ting the date and time on RDS receivers equipped with a clock.
The 730 Encoder may be manually set to the current correct
time, or it will check the time and date automatically if con-
nected directly to the Internet. Provision is included for auto-
matic changeover between Standard Time and Daylight Saving
Time (DST). This is detailed on Page 37.
DI
Decoder Information:
This is one of several ‘flags’ that convey
yes/no or other very basic data. This particular flag is meant
to tell the receiver whether the broadcast is monaural or is be-
ing transmitted in any of several methods of stereo or binaural
broadcasting. This is a rather esoteric and little-used function,
and only monaural and conventional stereo transmissions are
supported by the 730 Encoder.
M/S
Music/Speech Switch:
This flag indicates whether music or
speech is the primary programming. The purpose of this func-
tion is not covered well in the respective Standards, so it comes
as no surprise that it is not widely understood. In general, only
all-news or talk-radio stations would fly the Speech flag.
ODA
Open Data Applications:
The 730 Encoder provides a method of
transmitting ‘raw,’ proprietary hidden data within legitimate
RDS groups, including ODA, FFG and TMC applications. This is
a special use of the encoder for non-standard applications.
Additional notes can be found on Page 62.
PI
Program Identification:
This block of data identifies the broad-
cast station with a hexadecimal numerical code representing
the ‘digital address’ of the station. The receiver processes the
PI code to assist automatic tuning features (station memories),
and to prevent false switching to alternative frequencies that
might be shared by broadcasters in nearby regions. The code
is assigned by the broadcasting authority in most countries,
but in the US and in Canada it can be calculated from a numer-
ical encoding of station call letters. Encoder software does this
automatically as described on Page 42.
PS
Program Service Name:
This is the station’s ‘street name’ that
might typically appear on the receiver faceplate display. The
PS can be up to eight characters in length (including spaces)
and can be as simple as the station’s call letters (
KWOW
or
KWOW FM
) or a slogan (
NEWSTALK
or
LIVE 95
). As the Program
