[Elecraft] K2 frequency runaway

[Ron D' Eau Claire]

Eddi, DK3UZ, wrote:

>    A few minutes ago as of typing this, it happened again: While I was
> transmitting (not in split mode) the displayed (and transmitted) frequency
> slowly crawled upwards. It stopped crawling as soon as I stopped, and got
> moving again when I resumed keying. Curiously enough the frequency stayed
> put when I used the paddle instead of the manual key!
>
>    This reminded me of a piece someone else posted here about the encoder
> sitting right on a transition...

I am one of the ones who observed this happening in SPLIT mode, but it might
be the same thing. What I saw in SPLIT was that the transmit frequency
moved, but NOT the receive frequency. If it is a function of the encoder
reading the transition during key down, then the behavior in SPLIT would be
consistent with what you saw. The TX frequency can be changed while the key
is "down".

The fact that it stopped when you used paddles makes me think it might be
vibration caused by the key. I use a bug and straight key. The next time I
see it happen in SPLIT, I will try rapping on the table top instead of
keying and see if the frequency moves. That should at least identify whether
it is an electrical or mechanical cause.

If the cause mechanical, that might explain the rarity of it. Only those
with heavy hands on the paddles or using mechanical keys might be causing
enough vibration to trigger it.

Ron AC7AC
K2 # 1289