RCA 921  
Written by Accutron on 2017-05-08  

Devices included in this entry:

General Electric 921 gas-filled phototube (pictured in thumbnail)
RCA JRC-921 gas-filled phototube (pictured in thumbnail)


Introduced in 1939, the RCA 921 is an early cartridge type gas-filled phototube, similar in performance to the 930, with an S-1 spectral response and 800nm peak sensitivity. The 921 was once popular in light-operated relay applications.

RCA 921 Datasheet (PDF)


General Electric 921 and RCA JRC-921 gas-filled phototubes.

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

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