New amp build design - lots of features

[soundguruman]

Dear Tubeswell.
Didnīt you notice that pentode's plate signal goes *nowhere*?
That the control grid (closest to cathode) is AC coupled and has no DC reference to ground? (So Bias is impossible).
That the screen grid (the middle one) is DC connected to ground, not acting as a screen grid at all?
That the suppressor grid (closest to plate) is connected to +B through a 560K resistor, instead of being close to ground potential?

Are we all looking at the same schematic?
I mean the one shown in post #1.

I fail to see the "screen bypass cap".
And if you find the grid drawn closest to the cathode *is* the screen (not the usual way to draw it, that place is usually reserved for the control grid), where does that "screen" get its high DC voltage?

I just don't get how People can discuss the sonic effect of an unconnected and unbiased tube.

Like I said, it won't do squat.

[tubeswell]

Paggerman - Please correct the schematic in accordance with JM Fahey's earlier pointers.

[J M Fahey]

Yes please.
We, out of experience, "fill in the dots" or "cross the t's" in our minds, but, really, we are only guessing and itīs very easy to make mistakes.
Thanks, tubeswell.

[imaradiostar]

I think 100k is a good load. Also, I like having the pentode after a triode.

Of course, the pentode plate should be connected to something.

jamie

[paggerman]

Thanks everyone for your comments and feedback. Very much appreciated. I will, of course, update the diagram so that it makes sense and I will repost.

[Gingertube]

Jeff,
I would also change the operating point of the cathodyne (split load , concertina what ever you want to call it) phase inverter. Try 56K in anode and cathode with 1K5 as the bias resistor and add a bypass cap (22uF) across it. You can adjust the bias resistor later if required. I see that you have taken Merlin's advice with a big grid stop to the cathodyne splitter.

You indicated that you are in Oz. Should that be South Oz feel free to PM me. I have home workshop with Tube Testers, CRO, Sig Gen, all Merlin and Kevin's books etc., and 25 years as an EE in the day job.

Cheers,
Ian