Next RDS Forum meeting on 21 & 22 October 2024 at Geneva
RDS Forum - the association of RDS users
PS Implementation Advice
RDS Forum 2009 has adopted a Position Paper explaining why the PS name must be static and why dynamic/alternate PS is expressly forbidden in the RDS standard IEC 62106.
The Problem:
- PS is designed for speedy acquisition - of 8 characters, indicating the radio station's identity (PS name) and this being quickly received is critical to overall RDS usability.
- This PS can be held in receiver memory for even quicker recall upon selection of a preset.
- The use of PS, dynamically, will create display information that makes no sense in terms of the actual radio station name and saved in the receiver memory will cause significant confusion to the user when returning to a particular preset.
- Some RDS equipped radios automatically scan the FM band and use the PS of receivable programmes to display them with associated buttons for programme selection. Dynamic PS creates then labels that make no sense.
- Safety issue for car radios, which should not have rapidly changing displays; the transmission of PS, dynamically, causes rapidly changing displays that are clearly potentially distracting to a driver.
The RDS Forum 2009 Statement:
In short: It is recommended that the RDS PS feature is only used as specified in the RDS Standard and the use of dynamic or alternate PS should be prohibited. This is vital to ensure appropriate operation of hundreds of millions of RDS equipped radios in use, requiring compliant transmissions for correct functionality. The best practice to use dynamic text is to deliver it via the RadioText and RadioText Plus features only.
Click here to download the RDS Forum Position Paper in PDF format
Click here to download the PDF showing you a presentation on Dynamic PS vs. RadioText (RT & RT+). You can thus see yourself that text, if transmitted via the PS feature and RT, will sometimes result on modern radio receivers, with the RDS-RT feature correctly implemented, in some very uncommon display effects of that text information. On the other hand, text transmitted only with RT and RT+ can be displayed nicely, even on car radios and in addition with a very much reduced distraction effect. This presentation clearly demonstrates that the wrong PS use of RDS cannot much please many listeners and in addition, is very unsafe for drivers, because of the strong distraction thus created for drivers supposed to read those odd text elements, often with totally arbitrary word cuts produced by automated and normally not monitored text play-out systems. You will also understand then why the RDS Forum cannot support the use of text within the Programme Service name feature PS and considers this to be a wrong implementation of RDS. Text information transmitted over RDS must exclusively use RT and RT+ and not at all PS, which should be static and only show the PS name with a maximum of eight characters! Long PS with more characters can be used in addition, Regulators should also take note that international standards are there to be respected and broadcasters having created a work around should be told to stop this, also for safety reasons to avoid driver distraction (internationally highly recommended).