![History--Bell System television work in 1957 [telecom]](https://forums.cabling-design.com/media/22614/conversions/6036c00d294b61.10366873-medium.jpg)
The Bell System ran several ads in Billboard magazine touting its contribution to broadcasting. Billboard covered the entertainment industry.
On 8/12/1957, pg 15, Bell noted it's high speed broadband switching facilities that allowed advanced setup.
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On 3/9/1957, pg 16, Bell noted its automatic protection switching that instantly switched a bad TV channel to a backup so fast that the changed wasn't noticed.
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Also, back on 3/11/1944, an article describes the future plans of Bell and others to implement television transmission facilities to allow coast-to-coast broadcasting.
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On all of these, you can scroll through the entire magazine. Interesting business history.