Inovonics 510, Инструкция по эксплуатации и техническому обслуживанию

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T HE RDS DAT A GROUPS
The ‘Glossary’ utility of the Model 510 gives only the full names of
the RDS data groups. What follows here is a further definition of
these groups and their functions.
AF L ist of Alternative Frequencies: A “network” broadcaster, or one
with low-power rebroadcast transmitters to fill ‘holes’ in his
coverage area, can include a list of all frequencies where the
identical program can be heard. The RDS receiver, particularly
upscale car radios, constantly searches for the best signal that
carries the very same program. When a better signal is found, the
radio re-tunes with hardly any interruption. The principal utility
of this RDS function is with European radio networks and US
stations with ‘translators.’
CT Clock T ime (and Date): RDS can automatically update the clock in
the listener’s radio when the station carries this information. Of
course the time signal must be accurate, otherwise the radio clock
would reset itself each time the radio was tuned to another
station. Not only is it necessary to have time base stability, but
the proper offset for different time zones is part of the time
setting equation as well. Because of the grave responsibility that
this function implies, most US broadcasters do not provide time
data.
DI Decoder Information: This is one of several “flags” that convey
yes/no or other very basic data. This particular flag tells the
receiver whether the broadcast is monaural, or is being
transmitted in any of several methods of stereo or binaural
broadcasting. As many as 16 encoding options may be
accommodated! This is a rather esoteric function and, thus far,
remains unused both in Europe and in the US.
E ON E nhanced Other Networks: Used exclusively in Europe, this
feature allows the RDS radio to be updated about stations other
than the one being received. This feature finds utility in
situations where, for instance, an important speech is being
carried nationwide. Rather than relying on the AF feature to keep
the radio tuned to the strongest local signal, EON can tune the
receiver to another network that has the identical program.
E WS E mergency Warning S ystem: EWS carries coded information
regarding specific emergencies. Consumer RDS radios do not
respond to this data, but “special entertainment radios” carried by
emergency personnel would give an alert.
IH In-House Applications: This is a data channel set aside for
proprietary use by the individual broadcaster. It can be used for
transmitter or other plant equipment instrumentation, paging of
station personnel, or transmission of special messages to be
viewed by station management or even by employees of other
stations at remote locations. This messaging has some security in
that it requires a special decoder such as the Model 510. In-house