Fw: Re: [Boatanchors] Tube data

[J. Forster]

windy10605 at juno.com wrote:

> They generally draw more filament current, have larger cathodes, and emit
> more electrons. Many are designed for "off" and "on" (computer use).
> However I have also heard they are excellent for frontends due to "low
> noise". On the one hand "hot filaments" and "low noise" don't seem to fit
> together but I've seen several articles using 7044 dual triodes in the RF
> section.[snip]

The issue is S/N or noise figure, not just noise, and depends on the dominant
noise mechanism. You have to calculate the various contributions to the overall
noise.

-John