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813 triode connection

Posted by vinnie2 on April 20, 2017 at 10:01:23:
Trying to get some work done on actually building my 26/813/813 SE amp in between veggie garden and other yard work that is going on now. Ran into something I want to be sure I have correct. I have the 813 tubes hopefully connected in triode mode with G2 (pin 3) connected to the plate cap via a 200 ohm resistor and G3 (pin 5) connected to ground. Looking at the one channel of the working bread board I left assembled for reference, I notice that I have G1 (pin 4) connected to ground also through a 30k resistor, but I did not show it on the schematic nor do I see an explanation in my notes as to why I did that. Is it for the same reason as pin 5 going to ground, so that only grid 2 will be used as the cathode? In other words making it "triode mode"? Also why the 30k value for the resistor, and should I have a similar resistor between pin 5 and ground? Pinout for 813 is on the last page of the attached link.