Upvote:3
I think Radio was more revolutionary - is was the first
information distribution system.
The only "prior art" I can think of are medieval market-square announcers (heralds?), but they broadcast to a very limited audience.
In fact, it took about 20 years between the invention of radio and the start of public broadcasting - because the business model was not clear. TV was used for civilian broadcasts right away - without any period of "military-only technology".
In a way, the Radio/TV relationship is similar to the Telegraph/Telephone relationship. The first in each pair was a true revolution. The second was a crucial improvement.
Radio started public broadcasting. TV improved on it.
Telegraph started instant communications. Phone improved on it and made it a household item.