[Winky Dink]

Previous configuration was red (center tap) to 2nd RF grid.
I put red back to the center tap. Then disconnected black from 1st RF grid and connected it to 2nd RF grid.

Then I remembered to try it with the lid on the set. The lid blocks nearly all of the non-antenna signal. In that configuration the set receives normally, all stations volume-controlled--except for a negligible amount of the strongest signals getting through the cabinet.

So, it works well bypassing the 1st RF tube, 1st RF transformer, and 1st variable. condenser. I'm assuming there's a problem with one of those components or with the connections. Right now I'm removing the 1st RF transformer so I can inspect it thoroughly and check the continuities again.

The other part of the puzzle is that I cannot detect any signal if the set is connected to my usual 40-feet-around-the-ceiling antenna. I don't get any detectable signal unless I connect the antenna post to "earth ground." (I put that in quotes because it's not an REAL earth ground with iron rods 8 feet into the whatever)

And I would guess that the inability the get signal through my normal antenna is related to whatever keeps the signal from getting through the first RF stage.

I'll take a close look at the RF transformer, then try to simplify the results with only the essential variables.