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I know people use the WE 417a as a driver.
What I don't see is how can we get enough swing from it?
Biased at 25ma, 130vdc plate with -1 volt grid I see less than 50 volts peak swing and that's with a horizontal load line.
Most 300B tubes in SET need 80.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Follow Ups:
I wonder why WE didn't extend the published curves to show out to -5 volts grid?
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
-2.5v bias ~ 20ma ~ 183v across tube = 3.66 watts, about 80% of max dissipation (4.5 watts). Around 90-100v or so of swing, depending on load. Should be enough, fairly linear.
twystd
Besides, the driving voltage for a 300B depends on yhe operating point chosen: with more current and less voltage across the tube you are going to need less than 80V - let's say 65-70V for 100mA and 330V across the tube.
******
http://rh-amps.blogspot.com/
so bias it at -2V... When I ran it I was at a pair of NIMH cells in the cathode for a -2.6V bias.
dave
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