[Elecraft] [K2] LPF tuning for 20m

[Chip Stratton]

Hi Don et al -

I'm tuning up a K2 recently acquired from an estate. On transmit, tuning
C23 seems to be an on/off valve. On either side of a broad middle range
power output is very low, about 300 mW. The transition to a full 10 watts
or so is very sudden. Continued rotation it stays cons tant at that level
until an instantaneous drop back down to the 300 mW level or so.

Does this lack of a smoother change imply a problem with C23?

I have occasionally noted that even after having carefully tuned this LPF
that 20m CW power starts very low. After switching to another band and back
it usually normalizes. This even transmitting into a 50 ohm dummy load.
Seems it could be related to C23 behavior?

Chip
Ae5ka