Increasing tube reliability in industrial circuits

The 2015 August issue of Tube Collector contains among several other very interesting articles a reprint of the 1952 article "Increasing tube reliability in industrial circuits" by D. G. Koch.

The Tube Collector is monthly issued by the Tube Collectors Association.

Its President and Editor Ludwell Sibley kindly put the text at my disposal for publishing it here in RMorg.

The article is written by D. G. Koch, Tube Department, Radio Corporation of America, Harrison, N. J. , Product Engineering, June 1952

 "This article, courtesy of Bill Bright, gives an unusually straightforward discussion of the failure mechanisms of tubes and ways to avoid them.  It covers, for example, the start-up stresses on tube heaters in series-string operation (years before the big swing to controlled warmup time), and the audio hum arising in heaters.  It gives a sales pitch for the RCA "Special Red" line of 10,000-hour tubes - less the 5690 rectifier, on which the developers were still struggling to reach the required life.  -  Ed"

Please find this interesting paper appended.

Koch: Increasing Tube Reliabiity in Industrial Circuits (.pdf 760KB)

Unfortunately, Fig.8 was not included in the Word file I got. Therfore, a scan of this figure from the August issue is appended. 

Regards,

Dietmar

To thank the Author because you find the post helpful or well done.