Donating to Islamic Radio stations for Sadaqah Jaariyah

We cannot comment on Islamic radio stations since many Islamic radio stations broadcast talk shows and programmes which do not conform to the laws of Shari'ah. However the general principle in regard to Sadaqah-e-Jaariyah is that Sadaqah-e-Jaariyah will be obtained by spending wealth, time, energy, resources, etc. in any valid permissible cause which will benefit the creation e.g. Building a well, Musjid, Madrasah, teaching Deen, etc. As long as people benefit from that cause the donor will continue receiving reward.

And Allah Ta'ala (الله تعالى) knows best.