[Elecraft] K2 CW train of dots when ptt

[Giulio Pico]

I made yesterday the mod suggested by Don about having an external PTT
for CW, and a problem came up.
After I found the problem I have had a talk with the K2 owner and he
told me that the problem was present even before the mod ( He wasn't
bothered about this because he doesn't go cw on air... ).
Straight to the problem:
When I push the new PTT  in CW mode the radio starts transmitting a
train of dots when in iambic mode (tried A or B, no change) and a
fixed note when in straight key mode.
On SSB everything seems to work good, when i press the PTT foot switch
the radio goes tx regularly.
I don't use an external keyer, just a bencher iambic key connected
directly with the radio via the stereo jack on the rear panel.
I'm pretty sure about the mod (used a BS170 instead of 2N7000 and a
74HC153 instead 74AC153 but these shouldn't be a problem) and the
confirm of my friend who had this trouble before the mod made me think
about investigate somewhere else. He confirmed to me that when in CW
mode when he pressed the PTT on the mic the radio started transmitting
dots.
The key is not operational with the radio in any case (and wasn't
before the mod), neither on test mode. Tried to modify QSK delay with
no success.
Something suggest me that the problem could be in some software
configuration i can't find, or in the PTT/DOT coexistence on the same
pin of the key socket.

Any Idea????

TNX and 73 de Giulio IW3HVB

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