General Electric GL-1P39  
Written by Accutron on 2017-05-15  

Originally developed by RCA, the 929 / 1P39 is an early vacuum phototube with a semicylindrical photocathode surrounding a central anode. The 929 has a S-4 spectral response and a peak sensitivity of 420nm. The example pictured here is a second-source GL-1P39, manufactured by General Electric.

The RCA JAN-CRC-1P39 was the light sensing element used in the AN/ASH-4 Light & Time Recording Set, a device used to determine the yield of a nuclear explosion.

RCA 929 Datasheet (PDF)

General Electric GL-1P39 vacuum phototube.

This article is part of the [Detection & Imaging Tubes] exhibit.

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