From the wonderful world of long-forgotten technologies: the Radiovoter systems

[AlbertL]

One thing I really enjoy is learning about technologies of the past, electronic and otherwise, that never quite took off (at least in their time) for whatever reason - impracticality, lack of public/investor interest, high cost, safety problems, etc.  The June 1934 issue of Popular Science magazine contains two great examples, both from the same inventor.

https://books.google.com/books?id=wSgDAAAAMBAJ&lpg=PA37&dq=radiovoter%20system&pg=PA36#v=onepage&q=radiovoter%20system&f=false

The first, "Voting By Radio", describes a fascinating brute-force concept for achieving one of mankind's oldest and most elusive dreams - communication over power lines - for the purpose of recording audience response by radio broadcast listeners.

The second, "Radiovoter Gives Audience a Chance to Register Likes and Dislikes While Entertainment Goes On", discusses an RF system for recording responses from theater audiences - remarkably similar to the classroom "clicker" systems in use today.