https://www.thehenryford.org/collections/explore/artifact/285023
Pyrex Perfect Antenna Insulator, 1930-1939
Insulators--made of poor electrical conductors such as glass, ceramic, plastic, or composite materials--help make electric power and communication transmission...
antenna insulatorpyrexperfect19301939
https://www.printables.com/model/548920-antenna-end-insulator
Antenna End Insulator by W7AQB | Download free STL model | Printables.com
An end insulator for attaching the wire end of wire antennas at the ends opposite to the feed point. | Download free 3D printable STL models
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