Automation of Broadcasting Gear

[Rinehart]

Hello All,
For anyone who doesn't know already, I'm researching a book about nascent American television broadcasting. The first phase of the background reading for it concerned the technology of the time, and this is now largely completed--superficial, but enough to start with. Many thanks to all the people who took the time to answer my questions. I have moved on to the second phase which is concerned with the business aspects of TV--how network time is sold, the nature of affiliation agreements, and so on. Today I came across something in Successful Television and Radio Advertising by Seehafer & Laemmar (1958, McGraw-Hill) which I had never heard of before, and that is that in order to save on staff salaries, television stations began to automate the some of the hardware. By presetting the start and stop times of things like film projectors with a control console, you could play all the filmed commercials for an evening's broadcast without actually having a technician in attendance; slide projectors could be similarly controlled to do the opening credits of any station-produced shows, etc.
Does anyone know when this technology first came on the market, how much it cost, and how widespread was its use?