[Boatanchors] Max Plate Dissipation- Can You Fudge A Little

[Richard Knoppow]

----- Original Message ----- 
From: "David Stinson" <arc5 at ix.netcom.com>
To: <milsurplus at mailman.qth.net>; 
<boatanchors at mailman.qth.net>
Sent: Sunday, July 13, 2014 4:48 AM
Subject: [Boatanchors] Max Plate Dissipation- Can You Fudge 
A Little


>A 6AQ5's max plate dissipation is speced for 10 Watts
> in Class C service.  How long do you think I can get away 
> with pushing it
> up to 12 Watts?  Still staying within the max cathode 
> current specs, but just barely.
>
> 73 D.S.
>

   FWIW, I found the 10 watt value in the RCA tube handbook 
for triode-connected TV vertical sweep amp service. Nothing 
further in the Sylvania handbook.  An early ARRL handbook 
gives the dissipation for both the 6AQ5 and 6V6 as 8 watts 
as a transmitting tube.  Receiving type tubes generally do 
not tolerate the plates running with any color showing. I 
don't know what this amount of overload would do. If the 
plate does not show color it probably is safe as far as 
generating gas but I think you have to try it. Even if the 
tube works OK its life is likely shortened but I don't have 
any idea of how much. Someone else may have more definite 
information.


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