If this means a new QDX board, I'd recommend adding the integrator type wave shaping scheme described on page 6.64 of EMRFD, fig 6.114-E
The KD1JV Mountain Topper has integrator type keying giving a nice symetrical trapezoid using a PFET with cap from drain to gate for feedback.
There's also an optional zener diode in there to make rise and fall rates identical.
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That was developed in the old Yahoo AT_Sprint forum back in 2007 for the ATS3A.
Search for "Message: 1080 " in the following archive to see the rather long discussion:
I had no idea then that it was a decades old technique.
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Jerry, KE7ER
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On Thu, Nov 7, 2024 at 03:37 AM, Hans Summers wrote:
I do need to (when I am finished QMX SSB!) go back to QDX-M and finish the original intention: making the band configuration jumpers work for all bands 2200m to 6m, and testing/documenting the filter values?for those.?
