Radio News Magazine, December, 1947

The caption for this cover photo reads:

Tube aging rack at Hytron's Newburyport plant. An incandescent lamp, acting as a current limiting resistor, is in series with each tube element. This final seasoning and degassification operation results in the processing of more uniform radio tubes.

This issue of Radio News included articles on TV installation, composite transmission of audio and video signals for TV, and three separate transmitter construction projects.

I was interested to see ordinary light bulbs in use for manufacturing radio tubes. Some of us are still using light bulbs for diagnostic purposes (see The Dimbulb Radio Tester).

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