[Elecraft] [K3] Help with K3, TenTec TITAN amp, and QSK

[Paul Christensen]

> The K3's internal keyer does have a weight control which varies the
> dot:space ratio. This is not the same as the Logikey's K parameter,
> because the K lengthens the
> elements by a constant amount regardless of speed (the Logikey also has a
> weight adjustment if you wish).

Same here.  I use a microHam CW Keyer with K = 3 to compensate for a slight
bit of "dit shortening" with the K3.  The dit shortening is less problematic
in the "Old QSK" versus the "New QSK" menu mode.  I would love to see
variable K compensation added to the K3 that would function on both the
internal keyer as well as an external keyer.  Adjustable rise/fall CW would
be a very welcome addition at say 4 ms to 8 ms in 2 ms increments.

Part of the issue is in determining how to calculate the rise & fall time of
the keyed envelope.  This becomes more critical as CW rise/fall times
lengthen.  Myself, I would calculate the keyed element length by referencing
the mid-point of the slope.  K compensation would then be added or
subtracted from there.

If you calculate the keyed element length at the point where the CW RF
waveform just begins to rise and continuing all the way to the point where
it has completed falling to zero, then the K3 is dead-on when referencing an
external keyed closure.  But, that's not a practical method of determining
keyed waveform duration with a raised cosine slope.  Again, referencing the
rise/fall points mid-slope is probably the best compromise with ramped
up/down keying.  If we had that control, we could then put our keyers back
to K = 0 where they really belong.

Paul, W9AC