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ALTERNATIVE FREQUENCIES
As first mentioned on Page 10, the 730 accommodates as many
as 25 Alternative Frequencies, the maximum number supported
by the RDS/RBDS specification. These are other dial locations
where the very same program can be heard at the very same
time (in sync!). The RDS radio hunts for the strongest signal
that carries the program and seamlessly switches to it. This
feature is used by European radio networks and by independent
stations that have one or more rebroadcast ‘translators,’ ex-
tending coverage to areas where the main signal cannot be re-
ceived well.
Enter your Alternative Frequencies by checking
a box for every dial location that carries the
program. Always include the main transmitter
frequency, otherwise the RDS radio will not
switch back when it should. A button below
the Alternative Frequencies box allows all
checks to be cleared at once. The AF list is up-
loaded with the next
WRITE
command.
TRAFFIC ALERTS
The TP/TA function is a useful provision of the RadioData Sys-
tem, but one with potential for abuse. This is detailed on Page
12, along with a description of the TA Timeout Timer, a safe-
guard built into the 730 Encoder to prevent such abuse.
For a station to air TA (Traffic Alert) messages it first must be
listed as a TP (Traffic Program) station; that is, a station that
routinely includes traffic updates in the normal programming
schedule. RDS radios keep track of TP stations and ‘look’ for a
TA flag only from among those stations.
If your station does air
routine
traffic
an-
nouncements, check the
TP
box. This will then
permit the encoder to
send TA flags on demand.
In keeping with RDS and RBDS regulations, the TA flag is to be
sent only for critical traffic-related announcements, and then
only for the actual duration of the accompanying voice mes-
sage. We recommend using only the direct-connected, hard-
ware-switch activation of the TA flag described on Page 56.
However, as the encoder may be installed some distance from
the studio and addressed by a serial or network connection,
provision has been made to set the TA flag with a software
command.
