[Amps] Design VS parasitic

[Bill, W6WRT]

ORIGINAL MESSAGE:

On Mon, 24 Aug 2009 10:22:18 -0400, "Carl" <km1h at jeremy.mv.com> wrote:

From K8RI:  
> Wouldn't it be correct to say (paraphrasing): Designing a circuit to
> prevent parasitic oscillations rather than designing one to deal with
> the results of one?
>
From K1MH:
>How do you propose to do that when the tube itself is the source?

REPLY:

Not wanting to state the obvious, but having to anyway......

The tube is only an amplifying device. What it amplifies, and at what frequency,
are determined partly by the tube characteristics and partly by components
external to the tube. Since we can't get inside the tube, parasitic suppression
focused on the external components. Fortunately, with careful design, success is
assured. 

73, Bill W6WRT