These pictures and text appeared in magazine articles in 1939, and show
how the 14AP4 tube was made by DuMont.

Blowing the bulbs by hand
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Trimming excess phosphor from sides of 14AP4 picture tube
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Inspecting the tube for defects
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The steps in making the electron Gun
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Installing the gun
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Fusing the gun to the tube
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Sealing off the tube after heating and evacuating
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RF heating of the getter
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Pressure testing the completed tube |
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Here are some more detailed photos (courtesy of Mike Schultz)

The gun attached to the stem

RF heating of the getter |