What I understand from my knowledge that in those days there was only one powerful tower of broadcasting being set up by All India Radio through which Main station, Vividha Bharathi used to be available for those who had radio running on current, transistors, and through powerful antenna in the old model cars. Since the range of the AIR signal was 20 to 30 kilometers in those days, those antennas used to serve and give uninterrupted access to the AIR programs. Unlike now there was no continued playing of songs. Hindi and local language songs used to be played for one hour each in the morning, afternoon and late night. Some of the best programs which I have enjoyed during those days were Ek hi Fankaar, Chaya geet, Hawa Mahal, Aap ki farmaash, Chitralahari in Telugu, And all songs of a same movie is played in total. The songs were never disturbed with ads unlike now. The main station used to have news bulletin and skits.
'Idhuvum Kadandhu Pogum "
Even this challenging situation would ease