GET THE MOST OUT OF RDS
This is the last in a series of occasional articles to help you get the most out of RDS. Read them all at: radioworld.com/RDS. We will continue to update readers as new uses of the technology evolve.
a previous article in this series about RDS (RW March 13), I
wrote about techniques that can be applied to all of your metadata
delivery platforms to ensure your RDS displays make sense.
I’ll discuss common RDS problems and remedies.
or Program Type, is defined in the RDS standards as a
“descriptor” for your radio station formats; for example, the
numerical value 1 describes the format “News.” (Note that these
numbers involve one of the small differences between Europe’s RDS
and the U.S. RBDS standards. For example, a PTY of 5 in the European
RDS standard means Education, while in the U.S. RBDS standard PTY 5
sure that when you are setting up an RDS encoder, you have consulted
with the programming management of the station and selected the PTY
that most closely represents the station format.
the format changes over time, be sure to update it. I cannot tell you
how many times I have seen the wrong PTY set on a station. Often PTY
is set to the station’s previous format. While your particular
receiver might not display the PTY, many do.
Classic Rock station is transmitting an incorrect PTY code of 10 for
Country instead of 6 for Classic Rock on the author’s RDS receiver.
by Alan Jurison
are many newer program formats that do not have current PTY codes.
The newly released National Radio Systems Committee-G300 offers
recommendations in this area; see Section 4.2 and Table 2.
or Program Identification, is a unique four-character hexadecimal
identifier. In the United States, this value is determined by
NRSC-4-B Section D.7. In many cases, the PI code for your station can
be based based off of your call sign; for example, using NRSC-4-B
Section D.7.1, WHTZ would have a PI of 692B. Make sure when setting
up your RDS encoder that you have set PI properly as per the
applicable RDS/RBDS standards.
hardware manufacturers have improved their setup programs to help
with this, but ultimately it is your responsibility to set the
identifier correctly and unique to your service area. Note that
because of the use of RDS Traffic Message Channel (TMC) in the United
States, the NRSC has issued revised guidance in NRSC-4-B in Section
D.7.4; and NRSC-G300 section 4.1 further clarifies the issues. Using
the example above, because WHTZ is an RDS TMC station in North
America, its PI code becomes 192B. For some older receivers that use
the NRSC-4-A standard to “back-calculate” the call sign, this may
display as KDMH. NRSC-G300 Section 4.1.1 also issues guidance for PI
codes on FM boosters, translators and simulcasts.
PI issue is complicated in these situations, so the NRSC in the G-300
guideline recommends that receiver manufacturers no longer display PI
call sign back-calculations. The NRSC recommends manufacturers
instead use RadioText + StationName.Short. Thankfully, most radios do
not display or back-calculate call signs.
potential problem related to the PI being set incorrectly is that
some radios use the PI to determine alternate frequencies for your
station. While tuned to your station, the radio is scanning other
frequencies on the FM band with the same PI.
your main signal becomes weak and the other one is stronger, the
receiver will flip to the other station with the same PI. This is a
great feature; but I have seen cases where some clusters have never
calculated the PI and simply used the factory default on all of their
stations. Listeners then called and complained that the radio would
flip randomly to another station in the market.
stations had been set up improperly with the same PI code. Do not let
this happen to you! Each station in the market needs to have a unique
Alternative Frequencies, data is helpful for stations that have
multiple frequencies, such as a translator or simulcast partner.
this does not apply to your station, make sure the list is empty.
this does apply, make sure the frequency entries are accurate. If you
do not pay attention to this setting, you are opening yourself up to
a situation as described above, in which the receiver may tune to an
undesired station if your station’s signal becomes weak.
Service Centering is a popular method used to make the
eight-character PS look good on a receiver. If the PS contains fewer
than eight characters, RDS hardware and software vendors have had the
ability to “add” spaces to the field to make it appeared
was a big proponent of this until Insignia introduced the NS-HD01
portable HD Radio with analog FM RDS support. It has a bug; the PS
will not display if the first character has a space! It seems to the
user that PS frames are being dropped.
I am not usually a proponent of catering to a specific receiver
issue, I think it is in the best interest that we make the user
experience good on this radio, seeing how monumental it was to our
industry. Newer versions of the receiver have corrected the issue.
PS becoming less visible in new products, PS Centering and PS
Scrolling have started to lose their relevance.
forget RDS when you change station format. This might seem obvious,
yet I have seen stations overlook it. Plan to migrate RDS (and other
data services) as appropriate. Include these migrations in your
you cannot dedicate resources to switch your RDS during the format
change, at least make sure the RDS encoder is offline and not
injecting the subcarrier on the air. Revisit the RDS as soon as
Stations leasing RDS bandwidth or providing traffic information via
TMC should not disconnect their encoders due to a format change,
because you are required to always be transmitting RDS TMC data.
to inspect and review during a format change are the Program Type
(the format), Program Identification (did the call sign change?) and
default Program Service/RadioText messages. Make sure that you
replace all references to reflect the new format.
have seen stations that display the old station name and format
information not just for hours but sometimes weeks. Likewise, if you
do plan your RDS for the new format, be sure it does not get on the
air before the format does. That could be a spoiler to your surprise
I am travelling, I periodically scan the FM dial to see what other
stations are doing. I have seen problems with a station’s RDS
implementation and contacted the station; the people there typically
have no idea the problem exists.
your automation system lose its data link to the encoder? If so, you
might be stuck displaying old song data, although some solutions are
in the marketplace to address this and similar issues. There are also
some monitoring systems on the market to alert you if your RDS data
has a failure.
all of us have these tools available to us, but there are some simple
offerings that every station should be able to afford to help keep an
eye on RDS data and its performance. In many situations where I
observed problems, I found that the station engineer did not have an
RDS radio. Get one! There are many on the market, some now under $50.
your GM to buy a few inexpensive RDS-capable receivers for you and
other key personnel. Does the PD have a radio? He or she should be
watching. Consider getting a unit to mount in the air studio so the
personalities can keep an eye on the data.
you do not have RDS in the car, consider getting a radio that does.
Do your homework though; it can be difficult to find in the
aftermarket automotive receiver space these days. If you are buying a
new car, it is relatively easy to find a factory installed radio with
RDS. You can spend as little as $50 or as much as a few hundred
dollars getting access to RDS radios.
have several at my desk that I use to listen to my stations while I
work. I have RDS in my car, as well. You do not have to watch it
constantly, but keeping your eye on it and being aware is better than
ignoring this popular feature.
when your station is not transmitting RDS properly, your station’s
credibility and image suffer. For those who are selling
advertisements via RDS, or if your station is leasing RDS bandwidth
for traffic or other uses, this can cost you money. You probably
listen to your stations on a daily basis; just make sure you are
using a radio with RDS.
Jurison is a senior operations engineer for Clear Channel Media +
Entertainment’s Engineering and Systems Integration Group. He holds
several SBE certifications including CSRE, CBNE, AMD and DRB. His
opinions are not necessarily those of Clear Channel or Radio World.