[Elecraft] Power output measurement

[Ken Kopp]

I'd welcome your views on how to measure output power
of my newly-bilt K2 with resonable accuracy.  The operative 
word here may be "reasonable". (:-))

I have a quality 50 ohm dummy load, a Bird with a 50W HF 
element, the built-in wattmeter in the K2/KAT2, and an OHR
WM-2.  As one would expect, they all read differently ... too
differently.

At first thought one would might think the Bird should be my 
reference, but it's accuracy is +/- 5% of full scale ... 2.5 watts 
in this case.  I've calibrated the WM-2 with a Fluke DVM,
but the accuracy of the Fluke can only be assumed.  I don't
know enough about the sensing and measurement portion of 
the K2/KAT2 to have a "feel" for it's accuracy.  I also have
the Elecraft RF probe to use with the DVM, but no reference
for calibration.  Unfortunately I don't have access to a quality
'scope to use as a reference.

I tend to "trust" the WM-2 as it's accuracy is tied to the DVM
used to calibrate it.  The DVM is most likely my most accurate 
measurement device that I have available ... for now, at least.

73! Ken Kopp - K0PP
k0pp at arrl.net