I don't think its the placement of the transmit BFO frequency in the
filter, I think its overdriving the system and thus negating the keying
shaping by the ALC. I propose that a better and simpler cure for CW is
to reduce the amplitude of the oscillator driving the balanced modulator
(if the circuit is like the Corsair II) until there's no more ALC action
since there's no drive control. I'd take a 2N918, ground its emitter,
drive its base through a 1k resistor from a +12 CW point on the mode
switch, and hook its collector to the drive signal through a resistor or
potientometer to lower that drive until the ALC didn't affect CW anymore
and I think it would accomplish softening the keying.
A little more rise time on the CW keying envelope with maybe a few
milliseconds delay from shift to the rest of the radio being keyed on
should also help.
That's my current opinion.
73, Jerry, K0CQ
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