> Anyone with a critical ear (listen to W1AW on 14.047 and if you hear the
> difference between the note on LSB and USB and it is not pleasing to
> you....)
You're absolutely correct Clark. Listening between LSB and USB to 20-meter
W1AW reveals that the CW note is worse when listening in one mode over the
other (been too long since my research and I don't recall which sounds
better or worse). If you dig back far enough in the T-T archives, I believe
you'll see some discussion relating to this effect on W1AW that goes back at
least two years. I'm amazed that nothing has been done to improve the W1AW
20-meter signal.
Later this summer, I have plans on changing the ramped integrator on my Omni
Six. After working so hard to achieve a perfectly symmetrical wave-form, I
now want a fast (~1 ms) rise time and a trailing, asymptotic decay that is
characteristic of grid-block keying (e.g., Drake and Collins). After
spending countless hours in the QST archives, By Goodman, W1DX, had done a
remarkable job over the past fifty-plus years in researching and
experimenting with keying circuits in an attempt to achieve the "perfect" CW
wave-form. The sound of the classic grid-block keying circuit is music to
my ears: The note has an impulsive attack and a slight bell-like ring on
decay. I don't believe there is a single transceiver now being manufactured
that exemplifies this type of keying. Interestingly, I believe the only
change to the Omni Six will require movement of the timing capacitor on the
Control Board. The Omni uses the timing capacitor between the collector and
base of the second keying transistor. I will attempt to move one side of
the capacitor from the collector to the emitter (ground). I believe this
will accomplish the above.
-Paul, W9AC
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