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Traced the keying line through the rig and the critical waveform behavior for the trailing edge is the cutoff of the crystal oscillator/mixer combo.? The drop onset of cutoff for the other stages was extremely slow by comparison and could not have been contributory.?

An example of the fall time issue mentioned originally is shown in this scope shot.? Notice the near vertical drop in amplitude vs. time as the red arrow indicates.

Taking a closer look at the oscillator, with injection level set to 0.5V per manual, I would get the truncated edge on 40m.? If I increased the injection level amplitude via C66 trimmer to about 1.3V, then the keying waveform reverted to what I saw on other bands - a rise time still relatively short (around 2-3 mS) but not like the 40m, where the drop being almost instantaneous by comparison.?

The CW rise/fall (for all bands) can be adjusted by increasing the values of these two caps:

Rise - C204 - 0.1uF stock.? I added a 0.47 uF in parallel (0.475 uF total)
Fall - C70 - 0.005 stock.? I added a 0.47 uF in parallel (0.57 uF total)

The combination of these two changes resulted in a roughly 6 mS rise and fall time on the CW edge.?

Separately, I noticed there is a bit of first-dit-truncation - but it's possible that may have been the case before I made the changes.?

I'll run the rig on 40m CW for some rag chew over the next week and see how the signal reports are.? But judging from the waveform, I don't expect to get any key-click reports.?

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