[Hammarlund] John King Hq180 BFO

[Mike Taylor]

John,  Tube V13 is two tubes in one. V13B drives the "S" meter. V13A is the
BFO tube. I see on the schematic that the plate of V13A (pin #6) is placed
in circuit by the rear section of  S7 (the AM/SSB switch.) When S7 is in the
AM position, V13's plate should be out of circuit so that side of the tube
can't function. Maybe a mechanical problem at the switch? Or a wire has
broken off a wafer lug and touching something it shouldn't? Then again, I
also see that V13A pin #6 also is always in circuit with one of the plates
in the product detector tube (V9-pin#1). That's getting too deep for me when
it comes to armchair troublshooting. I'm no expert, but if all else fails,
the rear section of S7 might be a place to look. An interesting problem. I'm
curious to know what the fix for this would be. Keep us posted. Merry New
Year...Mike