Summary

Triode designed to be a replacement for the widely used type 201A.

As of 2014, the QRS Music Company produces and markets mechanical music items, and is best known for player pianos and rolls. The company is still very much alive and concentrating on their traditional market, but for a brief time in the 1920s, they also sold a line of radio tubes.

Physical Description

Tubular glass bulb with 4 pin American UX style base and red painted top, sectioned to reveal an unusual structure consisting of two triodes with their grids and anodes connected in parallel and their filaments connected in series. Mounted on a display block.

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