[jrblasde]

I’ve consulted a couple of the books which I got from Jim Koehler, Elements of Radio Servicing (Marcus and Levy, 1947) and Elements of Radio, Second Edition (Marcus and Horton, 1948). It looks to me that my Philco 46-480 has the AVC bus connected to the screen grid, the output of the preceding IF transformer connecting to the control grid, and the suppressor grid grounded. It seems a close design to this textbook example of a 1st IF section, except that this example only connects the screen grid to a fixed 100V rather than to an AVC bus.

   

   

And, just as I discovered and corrected on my own schematic, the control and suppressor grids are no connected together.