[Elecraft] K-2 #2636 Takes to the air!

[Tom Hammond NØSS]

Parker:

At 09:16 PM 11/16/02, Parker Buckley wrote:
>Made my first qso tonight with the K-2.  This is gonna be a
>blast.  Thanks for the coaching when I had a couple of
>questions, and thanks Elecraft for a great building
>experience!  Everything seems fine so far, except maybe the
>internal wattmeter.  When set at 5 watts, I'm getting 6 to 7
>on a WM-2 and a couple of older meters here.  Not sure how
>accurate it should be....5%, I think.  I have a week long
>trip (wish I could take it!), then will get back into it
>next weekend.

Congratulations on the completion of your K2 AND having already broken the 
ice, so to speak.

The 'wattmeter' in the 'basic' K2 is really nothing more than an RF 
voltmeter which supplies its RF voltage read to the CPU which than goes to 
a 'look-up' table to get a power to display.

The reading of the wattmeter sould be pretty decent as long as the K2 sees 
a 50-Ohm resistive load. Any other load scenario will result in a reading 
either over or under the real thing. More external wattmeters use  atrue 
directional coupler which should yield much more accurate measurements, 
even it the presence of less than perfect load situations... this is what I 
believe you are seeing in your comparison.

The above won't make your K2's wattmeter any more accurate, but maybe it'll 
at least help to explain why you're seeing what you're seeing.

Now... get out there and have some fun, rather than worrying about power 
disparities... <G>!

73,

Tom  N0SS