[Elecraft] K2 Power Adjustment/Output Question

[MikeH]

I'm wondering if I have a problem with the transmitter in my K2. I 
think other K2 owners will know if what I'm seeing suggests a problem.

In the process of comparing the power output reading on two different 
wattmeters, I found the same odd behavior on both (so I think I'm 
seeing K2 behavior, not wattmeter behavior). I was doing output 
measurements at different power levels on the K2. So, for example, I 
would start at a few milliwatts, transmit into the dummy load, record 
the measurement, move up to say, a watt, and repeat the process. I 
would continue up in power a watt at a time, recording the output on 
the meter.

What I noticed is a failure to always get the same wattmeter reading at 
a given K2 power level setting (as shown in the K2 display). For 
example, at 0.7 watts (on the K2 display), the meter showed 1.0W. When 
I moved the K2 power adjustment up to 1.0W (on the display), the meter 
showed 0.8W. However, when I turned the K2 off, and repeated the 
measurement at 1.0W, the meter then showed 1.0W again. I then turned 
the K2 power adjustment down a bit (without transmitting), then turned 
the adjustment back to 1.0W, and got only 0.8W on the meter again. 
Tapping the key a few times at that power level did not bring the 
reading back to 1.0W on the meter. Yet if I turned the K2 power knob up 
(without transmitting), and then back down to 1.0W and transmitted, I 
got 1.0W again. This sort of pattern was repeated throughout the 
process. I could set the adjustment on the K2 for a certain power 
level, get a reading, and then get a different reading after doing 
something like turning the rig off or changing the power and 
transmitting, or just moving the adjustment up and/or down, and then 
going back to the original power level setting only to get a reading 
that was off (always lower) by as much as 1W (say 3W rather than 4W). I 
could always do something to get back to the original reading (like 
powering down the rig, or changing the power level and tapping the key 
a few times)  and  then remeasuring. Simply tapping the key a few times 
does NOT bring the wattmeter reading back to the original reading 
UNLESS I also change the power adjustment on the K2 (and then remeasure 
at the original K2 setting).

So, does this variance of up to 1W while measuring output at a given 
power setting on the K2 represent a problem with the rig? I experienced 
this variance regardless of whether the rig was putting out 2W or 10W.

A couple of basic facts: the maximum power output for the rig is 12W 
from bands 80M-20M; 10W on 17M-12M; and 8W on 10M. Whenever I transmit, 
the output appears totally stable while keyed down. Signal reports have 
all been good. Also, I do have the KAT2 installed (I get the same 
behavior even if I turn the tuner off at the menu), and I don't think I 
have power reading setting (via R1 adjustment) set as accurately as I 
could. However, since I can replicate this issue with the tuner turned 
off, I do not think that is a factor.

As always, I appreciate your thoughts.

Mike Hagey NR7F