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

[Bob Camp]

Hi

How much air to you want to blow past it (more is better)?

How long do you want it to live (many years or a couple days)?

Who made the tube (and how well did they make it)?

What kind of socket is it in (ceramic is better than phenolic …)?

Is there a shield on it (hopefully not ..)?

There are a whole lot of variables. For hand keyed CW at a 30% duty cycle you can get away with a lot more than 100% transmit on an FM repeater.

Simple answer - the cathode and how it’s built probably will be the bigger issue than the plate. You can *look* at the plate and see how hot it’s getting (it glows…). The cathode does not communicate it’s problems quite as clearly.

Bob


On Jul 13, 2014, at 7:48 AM, David Stinson <arc5 at ix.netcom.com> wrote:

> 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.
> 
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