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First RDS Specification published over 30 years ago

The RDS specification was adopted by the EBU (European Broadcasting Union) and in 1984 EUROTECH (the association of European consumer electronic manufacturers, now called Digital Europe), published and also submitted to the ITU and CCIR Study Group 10 in particular. This Study Group extracted the essential characteristics from the EBU specification and transcribed them to ITU-R Recommendation 643 which was then adopted in 1986, updated in 2012.

RDS has emerged over the time and exactly within the years 1975-1984. In the retrospective we see in this 10 year long development appearing:

  1. The desire, to universally identify each FM programmes; this created the PI and PS features.
  2. The desire, to identify broadcasts for motorists more universally than ARI; this created the TP and TA features.
  3. The desire, to hand-over a mobile receiver within a network; this created the AF feature.

Also, there was a desire, less strong however, to identify speech and music and programme type; this created the MS and PTY feature. A system was then designed for the mobile listener who had needed, without any doubt, much help with in-car reception of FM, for the various reasons established by audience research; namely automatic retuning from one transmission coverage area to the next area and so on; and also, an emulation of the ARI system used in Austria, Germany, Luxembourg and Switzerland, which RDS at the end has totally replaced offering identical features with TP/TA and which still nowadays alert drivers to traffic announcements.

RDS was designed for mobile reception

Many other features were proposed and built into the RDS system to be dynamically multiplexed as needed in each transmission. The key mechanisms were designed for mobile reception and a group/block data format to ensure very fast data synchronisation and decoding of certain features whilst allowing some features to be conveyed at a slow rate for general information. Since the system design was developed by broadcasters working in the well regulated environment of the 1970s, a number of features were considered, but not fully developed at that time. As future enhancements were expected right from the beginning, this has allowed RDS to mature over the following years.

In 1985, EUROTECH agreed with the EBU about the general introduction of RDS and promised, on the condition that the EBU would give their support to the development of the RDS-TMC feature that the first RDS receivers would be presented at the international consumer electronics show IFA’87 in Berlin. From 1988, these receivers were then marketed in all those countries where RDS was already introduced.

Given the fact that the RDS development was so well co-ordinated by the EBU and broadcasters in all European countries were, through this activity, fully aware of the benefits created for their listeners (some said they could now surf the radio waves), the introduction of RDS, European-wide was quite fast. So fast, indeed, that some then called it the “silent revolution”.

Broadcasters started to implement RDS transmissions, with a mixture of self built RDS encoders and there was a beginning of a small specialised professional equipment market selling RDS encoders and associated RDS monitoring equipment. The earliest implementations were undertaken by some large network broadcasters and they selected just a few RDS features to start their trials and pre-service activities. Within a couple of years some problems had come to light as these initial transmissions began to give evidence that the original RDS specification was somewhat lacking when “real world” situations were faced.

First RDS industry standard published in 1990

Then new RDS features like EON and ODA were added to the first RDS European standard issued by CENELEC in 1990, and in the year 1999 RDS finally became a world IEC standard, again with some new RDS features, like RT+ and eRT, being added, last updated in 2014 as IEC 62106 ed 3.

In the USA, because of different radio broadcast practises, an adaptation of RDS was required and a Subcommittee of the National Radio Systems Committee – NRSC – created in 1997, in coordination with the EBU, the RBDS variant, issued by the NRSC then as a voluntary industry standard of NAB (National Associations of Broadcasters) and the CEA (Consumer Electronics Association).