[Elecraft] Peculiar problem on 80 M

[Stephen W. Kercel]

Fellow Elecrafters:

I have a strange problem with my K2/100 on 80 meters.

The situation is as follows:

I work QRP DX at the low end of 80 M, (say 3508 kHz or thereabouts) 
with a requested power of 4.5 watts, and get an indicated 5 watts out.

I then check into the Pine Tree Net on 3596 kHz and crank up the 
requested power to 10 watts (this is before the relay clicks; I'm 
still in QRP mode), and I get about 10 watts out. So far so good, right?

Then I go back to 3508 kHz, without resetting the power request level 
knob, but the rig puts out 5 watts, even though the display 
acknowledges my ten watt request. If I go back to 3596 the output 
goes back to 10 watts in agreement with the requested level.

Note the essential point, when I make a big excursion in frequency, 
the radio is putting out a level of power substantially different 
from the requested level.

I can correct the output level at the low end by sweeping the 
requested level either low (near 0) or high enough to make the QRO 
relay click, and then adjust it down to and desired QRP level, and 
the rig will put out approximately the requested level of power.

The phenomenon occurs whether I change frequency by switching VFOs 
preset to the two frequencies, or if I retune one VFO using the tuning knob.

This is not an issue of varying antenna impedance. I get this effect 
with a commercial dry dummy load as well as a real (very well matched) antenna.

I can also create the effect the other way around. If I request 5 
watts at the 3596 then go to the low end and request 10 watts, then 
go back to 3596 with the knob in the 10 watt position, I still get 5 
watts until I jigger the power level request knob.

I have tried to reproduce this effect on 40 meters, requesting 5 and 
10 watt levels at frequencies differing by about 100 kHz. In that 
case I get what I would regard as normal behavior. The rig always 
puts out the approximately the requested level of power irrespective 
of when I set the power level request knob.

Has anyone else run into this phenomenon?

Is it a quirk in the software?

Is something wrong with the radio?

73,

Steve Kercel
AA4AK