Find pin 6 on V206, the 6AQ5 speaker-amplifier tube socket.
The foil trace leading away from this pin is where the positive side of the ping cap is connected. Sometimes you'll find it simply lap-soldered to this foil trace.
The schematic shows C243 connected here, marked 2 uf. If that spot on the top side of the pc board is empty, your ping cap has been located somewhere else.
Some receivers have one section of the mode selector wired to that foil trace, with a wire leading to one 4uf cap for AM and another that's selected in sideband modes. They're on a tie strip at the rear edge of the main receiver pc board, under the deck. This is also a common place to connect a larger-than-stock cap to get a long ping. The ping can be really annoying on sideband, and this lets you wire that cap for AM only.
But since the ping cap is not factory installed, where you find it is the result of a custom mod, not a factory standard.
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