http://www.ace-xtra.com/rdsxtra.htm

This unit sits between the tuner and the antenna, and
"inputs" RDS-text showing the current indoor and outdoor temperature.

I seem to remember that the RDS-data could be picked up, even when playing MP3s? And then put in an "overlay" over the screen at a particular button-press? Any comments?

Marius (Escort Cab + Mark II)