For those who don't remember, on powering up really old televisions the image would start as a dot in the middle of the screen, and then expand. It might only take a couple of seconds to a few seconds to reach full size. The reason for this is that old televisions used vacuum tubes instead of transistors, and these needed warming up. I remember going to a repair shop that had dozens of different types of tubes for replacement parts.
Sometime in the mid-1970s, manufacturers began to advertise televisions that were "Instant On". Since many of these TV's still used vacuum tubes, I noticed that these TV's kept some of the vacuum tubes powered up even when the TV was "off". I could tell because most vacuum tubes glowed. Many old televisions had heat vents toward the back and an orange glow would emanate from these vents. It would light up the wall behind my television. The TV also put out a great deal of heat.
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Best wishes,
John Coffey
http://www.entertainmentjourney.com
Sometime in the mid-1970s, manufacturers began to advertise televisions that were "Instant On". Since many of these TV's still used vacuum tubes, I noticed that these TV's kept some of the vacuum tubes powered up even when the TV was "off". I could tell because most vacuum tubes glowed. Many old televisions had heat vents toward the back and an orange glow would emanate from these vents. It would light up the wall behind my television. The TV also put out a great deal of heat.
--
Best wishes,
John Coffey
http://www.entertainmentjourney.com
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