all about the U.S. dollar symbol — $.
Example of a station transmitting 0x24 ($) to the RDS encoder in a 2014 Toyota Tundra, international currency symbol is displayed instead as per the RDS specifications. Photo by Alan Jurison.
you are a reader of Radio World, you may have seen my series of articles
regarding optimizing RDS displays over the past few years (radioworld.com/RDS).
While I have focused on implementation, I never communicated how this interest
of mine came to be.
was really a marriage of two interests in life, radio and computers. I was
involved in the early 1990s with Bulletin Board Systems — a world that existed
before the Internet that we know today came to be (http://bit.ly/1eCEecG). I started as a
user, later as a System Operator at age 13 no less, and that interest grew into
participating in interconnecting BBSes into networks, and even delving into
beta testing and programming for my preferred BBS Software, T.A.G. (http://en.wikipedia.org/wiki/TAG_(BBS)).
was “bit by the radio bug” around this same time. The Internet we know today
would quickly end the world of BBSes, and I transitioned into the beginning of
my radio engineering career. I started getting involved with RDS when it
finally started to gain in popularity in the United States in the early
broadcasters had started implementing the technology. Eventually my company
became interested in doing some RDS deployments.
building blocks of RDS and BBSes were really the same. Both used RS-232 serial
connections to devices and used special command sequences to configure
properly. Of course, RDS encoders produce a data stream that can be decoded by
many radio receivers at the same time. So, I had the building blocks,
computers, data links, and this new RDS encoder sitting on my bench.
that point, I was learning RDS along the way, catching up with the groundwork
many others had laid in the 1990s. I started like many engineers who get
involved with new technologies, I took RDS encoders out of the box and started
bench-testing them. I used the manual as my guide on how to set things up.
eventually put stations on the air, and I would watch how what we were sending
over the air appeared on receiver displays with RDS. If you ask my co-workers
at the time, someone would get a new car with RDS and I’d ask to borrow their
keys and be out in the parking lot watching, learning — and essentially
adapting techniques used in the transmission of RDS to be most compatible and
visually appealing across a range of receivers.
of the things that always perplexed me was that the U.S. dollar sign ($) often
produced different results, depending on what radio receiver I used. Many
stations just avoided its use altogether — which sometimes hurt efforts to
monetize RDS to recoup the investment in the hardware and software required to
the problem is, if you wanted to state a price point for an advertiser, the $
issue became a hindrance. If you wanted to promote your own brand and talk
about that $1,000 cash giveaway Monday morning at 7:20 a.m. — you really couldn’t
do that effectively, either.
I may have picked up on a lot of tricks on how to optimize RDS displays, the
dollar sign problem escaped me. It wasn’t until this series on RDS in Radio
World started that some of the industry’s engineering leaders reached out to me
to get involved in the National Radio Systems Committee. Barry Thomas, then
with Lincoln Financial Media, and Steve Davis of CCM+E said the NRSC was
starting to work on a guideline document to pool together all the best ideas of
RDS technologies from many different viewpoints into one document to be, in
essence, as a guide for the station engineer taking that RDS encoder out of the
box for the first time. I was intrigued and was happy to start participating in
we worked on what was to become NRSC-G300, the RDS Usage Guideline, in one of
our discussions, I mentioned the dollar sign issue to the group and that
brought up varying experiences from other broadcasters as well. Mike Bergman,
then of Kenwood and now with CEA, used his experiences of implementing RDS in
receiver designs to put the pieces together and solved the puzzle.
Example of a station transmitting 0xAB to the RDS encoder as recommended in NRSC-G300 to display the U.S. dollar sign ($) in a 2014 Toyota Tundra. Photo by Alan Jurison.
noticed that the U.S. dollar sign or $ is denoted as 0x24 in hexadecimal format
in ASCII but is a different value — 0xAB — in the RDS standard. Mike and I
later did some field-testing using several RDS encoders and RDS receivers.
Finally, we got to the bottom of this.
this same time, recording artist Ke$ha became frequently played on many
stations, and her popularity also helped highlight this issue even further. The
end result of our RDS research is in NRSC-G300 released Sept. 2012, Section
you are interested in learning more about this problem, the section covers RDS
and character/font sets, and I encourage you to review them. As the NRSC
investigated, we discovered several other characters that have similar issues.
on just the dollar sign, here are some excerpts from NRSC-G300:
two most common faulty behaviors are due to the following:
Receivers sometimes are displaying the ISO-8859-1 or Arial font equivalent
graphic for 0xAB (which is ‘«‘) rather than the RDS Standard graphic at 0xAB
(the U.S. dollar sign, “$”). However, other character sets have also been observed
Broadcasters sometimes are using the ISO-8859-1 value of 0x24 for transmission
of ‘$’, leading to RDS-compliant radios displaying the international currency
symbol, “¤”. Broadcasters should be transmitting 0xAB for the U.S. dollar sign ‘$’
in the RDS character map.
offers guidance on how to best tackle this problem with specific
recommendations for RDS equipment vendors (Section 8.2.1), broadcasters
(Section 8.2.2) and receiver manufacturers (Section 8.2.3). It is our hope that
this information will fix both the transmission and the receiver implementation
issues surrounding this problem.
was released about a year and a half ago, and I still see this problem in my
travels across the United States. With the globalization of many automotive OEM
receivers, I have found that many new receiver designs today are following the
guidelines in Section 8.2.3.
I have found that RDS equipment vendors and broadcasters have not adopted the
recommendations the NRSC outlines in G300. I’m hoping this article raises
awareness so we can solve this issue once and for all.
the NRSC suggests that RDS encoders and RDS software solutions used in the
United States have a feature added that could be enabled to translate 0x24 to
0xAB so that the character would display properly. This seems to be the best
solution to this problem; however I am not aware of any products sold on the
market doing this currently.
broadcasters can modify their systems to make the translation. This is the path
that Clear Channel Media + Entertainment chose, and we implemented this across
all our RDS enabled stations in early 2014. I personally hope that the rest of
the industry can work towards transmitting the proper character 0xAB via RDS PS
and RT when a dollar sign is to be displayed and, over time, as more
internationalized RDS compliant receivers continue to be released, we can
finally solve this problem.
Alan Jurison is a
senior operations engineer for Clear Channel Media + Entertainment’s
Engineering and Systems Integration Group. He also chairs the NRSC RDS Usage
Working Group. He holds several SBE certifications including CSRE, CBNE, AMD
and DRB. His opinions are not necessarily those of Clear Channel, the NRSC or