[Boatanchors] When Were Metal Case Tubes First Produced?

[John Pelham]

Metal tubes were announced by RCA in 1934, but individual types were 
introduced starting in 1935.  To pick your two examples, 6H6 was introduced 
in August 1935, 6AC7 in March 1939.  (Credit to the book Tube Lore, by 
Ludwell Sibley, for the dates.)

73,
W1JA
John Pelham
Web site   http://www.radiophile.com

----- Original Message ----- 
From: "J Forster" <jfor at quik.com>
To: "Milsurplus" <milsurplus at mailman.qth.net>
Cc: "BOATANCHORS" <boatanchors at mailman.qth.net>; 
<BOATANCHORS at LISTSERV.TEMPE.GOV>
Sent: Friday, May 23, 2008 5:39 PM
Subject: [Boatanchors] When Were Metal Case Tubes First Produced?


> Does anyone know when the metal cases tubes (6H6, 6AC7,...) were first
> introduced?  Was it before WW II?
>
> Best,
> -John