Just returned from a little family vacation, so I haven't gotten any farther with this. Here's the Philco sweep schematic for what it's worth:
http://antiqueradio.org/art/Philco49...pSchematic.jpg
I'm hearing a rapid ticking from the chassis, seems about vertical speed. The HV cage has been cleaned and shows no signs of past arcing. No signs of arcing anywhere, in fact. I hope this does not mean a vertical transformer is funky . . . .
Tomorrow, maybe I can locate my favorite listening tube and try to locate the ticking source. Will fire up the scope, as well.
Again, I have replaced all paper & electrolytic caps, plus C508, C516 and C517 in this schematic. I measure 327vdc on the 320v line.
Phil Nelson