I was operating barefoot for the contest, so no QSK. My Henry linear doesn't have QSK capability natively. I've thought about adding it, but it would be expensive and a good-sized project.
I use an external keyer (K1EL). I don't even own the FT-980 curtis keyer pcb. I'm so used to the K1EL that it would be issue to swatch, I think. WIth the K1EL I've never received any feedback on a shortened initial dit, and I haven't noticed any miscopies that would indicate it. I also suspect it might be a curtis interaction with the FT-980. I note that it looks like the board was upgraded for later radios (FT-902, etc), and maybe they fixed this issue. The PCBs are backwards compatibile I believe.
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-Mat Breton, N8TW
Mat Breton N8TW