[Boatanchors] 211H differences

[Richard Knoppow]

----- Original Message ----- 
From: "Chuck McGregor" <cbmcgr at gmail.com>
To: "mac" <w7qho at aol.com>
Cc: <boatanchors at mailman.qth.net>; "Robert Goff" 
<robert.h.goff at gmail.com>
Sent: Saturday, January 26, 2013 2:53 PM
Subject: Re: [Boatanchors] 211H differences


> The 1945 Amperex sheets in Radio's master indicate the 
> "Type 211H fully
> interchangeable with Amperex HF-150"  and also " Type 211C 
> fully
> interchangeable with Amperex HF-130".  Unfortunately no 
> detailed spec's
> given.  Possibly the 211H and 211C had higher plate 
> dissipation ratings
> than the plain 211 ?     Same note repeated in 1950 
> edition, with no
> further information.
>
> 73,
> Chuck K7MCG

     Here is some information about 211 tubes from _Radio 
Handbook_ 11th edition (1948)  Listed are:  211, 211-C, 
211-D, 211-H AKA HD-211-C
Maximum plate voltage is 1250V for the 211, the C and D, 
1500 for the H.
Plate dissipation is 125 watts for 211 and 211-D, 125 watts 
for the 211-C and H.
Power output for a single tube in Class-C telegraphy is
100 watts for the 211 and D and 148 Watts for the C and H.
Manufacturers are listed as:

211; Westinghouse, RCA, General Electric, Taylor
211-C; Taylor, Amperex
211-D; Taylor, Amperex
211-H; Taylor, Amperex

     My BC-375-E however, has 211-D tubes made by General 
Electric so don't think this list is complete.
     The _Radio Amateur's Handbook_ 1944 edition lists the 
211, 311, and 835 together. The only differences listed are 
interelectrode capacitance. A note says the 835 is an 
obsolete type.
     The 211 is also listed in the _RCA Transmitting Tube 
Handbook TT-3_ dated 1938.  This book says the maximum 
frequency for full ratings is 15 mhz. It seems to me the 
later versions may go higher.

     BTW, I also have a pair of very early Western Electric 
211's that have sheet metal plates of some sort rather than 
the carbon plates in the later tubes.


--
Richard Knoppow
Los Angeles
WB6KBL
dickburk at ix.netcom.com