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Old October 1st 17, 02:31 PM posted to rec.radio.amateur.boatanchors
Scott Dorsey Scott Dorsey is offline
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First recorded activity by RadioBanter: Jul 2006
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Default suppressor grid modulation?

In article , philo wrote:
On 09/30/2017 10:47 AM, Scott Dorsey wrote:
So, if I adjust the voltage on the suppressor grid of a pentode I can alter
the gain of the tube substantially, but in the process I now am moving most
of the current from the plate to the screen grid.

Are there any tubes out there with a sufficiently heavy screen grid that
this could be done with? I can always reduce the total current to prevent
screen grid damage but then linearity suffers.

Do any small signal pentodes out there exist with heavy ruggedized screen
grids?


Sure that was done plenty of times back in the old days.

I think some of the cheaper Heathkit transmitters use SGM


No, other way around, I want to modulate the suppressor and not the screen.
Screen grid modulation is... not really very linear at all but requires
little drive, which makes it a win for inexpensive communications grade
radios.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."