/diy/ - Do It Yourself

>>1916006
Alright fellas, say I wanted to make an active low pass filter with variable Q and variable ƒ. Pretty simple, right? Now say I wanted to do the same thing with discrete components, like say a triode or two (not gay, btw). Where can I go to either see some circuits of such a device or learn how best to approach doing this? An active, variable ƒ lpf seems easy enough with a Sallen-Key cathode follower, however the <1 voltage gain leaves me no room for varying Q by changing K from 1 through 3, right? What am I to do? Any tips or a good direction to start doing a little learning would be greatly appreciated.

>>1880918
Any /tube/ dudes here? Can any one point me to to resources to learn to design pentode circuits? I am pretty good with triodes and have designed circuits with them successfully, but information about their operation and implementation seems to be much more forthcoming than for their five element brethren. I have something I need to design and build which requires a pentode driver and I could just use some off the rack schematic that every one uses but that isn't any fun for me and I don't like building shit that I don't completely understand.

Thank you.