[Milsurplus] BC-474 "Frnge Howl"

[David Stinson]

The Signal Corps was aware of this problem with the BC-474.
TM 11-250, Change 2, page 7 dated 28 Oct. 1942 addresses it.

They call it "fringe howl" and suggest using the metal outer
shell of a "D" cell battery as a shield, using a strip of metal
connected to the nearest ground screw to press against
and ground it.

There's also TM 11-4006, "Repair Instructions" for
the BC-474 dated May 1945 
(so much for them not seeing long service ;-).
Page 39 covers moving the lead of electrolytic C-13
off the emission switch (which it will eventually destroy
through switching surges) over to the unswitched side
of the transmitter B+.  This is a "must do" change for 
any BC-474 owner.  Actually- unless you're running
it on the genny, you should just disconnect this cap.

73 Dave AB5S