Plasma Labs A-201  
Written by Accutron on 2017-02-21  

The Plasma Labs A-201 is a 10KHz polyatron or 'inverse dekatron'. Instead of having a central anode surrounded by a ring of cathodes, polyatrons have a central cathode surrounded by a ring of anodes and a screen electrode. This arrangement prevents the cathode poisoning experienced in traditional dekatrons, but the polyatron structure prevents direct viewing of the count through the top of the tube. With an operational polarity like that of a beam switching tube, the A-201 can directly drive a Nixie tube for count indication.

Plasma Labs A-201 polyatron.

A-201 polyatron, top view.

This article is part of the [Glow Transfer Counting Tubes] exhibit.

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