The PA28 Warrior I currently fly has a KY196 Radio in the Com 1 position, and KX155 TSO Nav/Com in the Com 2 position. With regard to the EASA/CAA regulations, do I have to upgrade both radios to 8.33kHz or just the one as a legal minimum. The aircraft is used to fly in IMC conditions as I have an IMC IR(R) rating.
I can't seem to find the exact regulation on line. Can anyone help and please clarify?