[Elecraft] Do I have a problem? I do have questions! (long)

[Max Moon]

Hello,

I just bought used K2 #9xx and have no other experience with the K2. I've
noticed several things which may be problems. In addition, I'd like to add a
couple of accessories and whichever of the Rev. B mods that make
sense--which probably will influence what I should do now (or later) about
any problems. I've been reading the documentation that came with the rig,
studying the Elecraft website, and going through the reflector archives--but
there's so much information that I'm not sure how to prioritize or apply it
all.

1.  In switching filters, the received CW signal changes pitch both up and
down, depending on which of the four bandwidths is selected. In addition,
the 2nd filter (0.7--all are at default widths) is muffled or noisy, unlike
the others. (In other words, how much variation is acceptable--these changes
are definitely beyond the 10-20 Hz DAC variation I read about.)

2.  I sometimes draw more than 2.3 A getting 5W indicated CW output, at
other times or on a different band less than 1.9A. (Again, some difference
in current draw, just like output, is reported--but what are the
guidelines?)

3.  The OHR WM-2 (which I re-calibrated a couple of months ago) never shows
5W output, rarely shows 4W, & sometimes not even 3W, even though both the K2
bargraph & LCD display show 5W. (Sometimes when I tune the antenna at 2W
(indicated by the K2) the WM-2 shows 3W, and when I go back to up to 5W on
the K2, the WM-2 is still less than 4W.) (The WM-2 is inserted between the
K2 and the ATU & has seemed consistent in the past.)

Here are a few details that may be relevant. What I want is an optimized CW
QRP rig. The NB, SSB, and I/O accessories are installed  (I didn't know that
either the SSB or I/O was installed, the seller didn't mention it in his ad
& I didn't think I needed them.). The K2 has F/W 2.01 & I/O F/W 1.02. I plan
on installing the AF and 160M accessories and probably the DK3RED approx. 5W
power control limit mod.

My questions:
1.  From what I mention, does it sound like the K2 has any problems?
2.  If so, where do you suggest I look for solutions? (I've already gathered
up the filter adjustment/alignment info at the Elecraft site & there seem to
be so many different approaches!!)
3.  What Rev. B mods do you think are essential for a CW/QRP-only K2? (my
impression is that the "BFO Toroid & PLL Ref Osc Xtal Upgrade" and "2nd
Filter Upgrade" make sense--do you agree?--but I don't know about any of the
others...)
4.  Another part of the Rev B mods is updating the F/W or I/O F/W? (If I
understand correctly, the differences between new F/W and my 2.01/1.02 F/W
wouldn't improve CW QRP operation much--what do you think?)
5.  Are there any specific mods you'd recommend for a CW/QRP K2? (My
thinking is that the 7-matched-crystal CW filter mod might help but I don't
know what else, not even whether it's worth going all the way & doing the
14-crystal swap...)
6.  Given my plans to install the AF & 160M plus (probably) some of the Rev
B mods, would you suggest that I tackle these matters in any specific
sequence?

I did get on the air yesterday with my Cushcraft R7 vertical. My first K2
QSO was the main Marconi centenary station on Cape Cod, then Cuba (both on
10M), next an Argentine ham (12M), finally another of the Marconi stations
(40M). I know I'm going to like it here!

Thanks very much for your time.

Max, k0max