[Elecraft] KPA100 power measurement

[Joe Borrello]

I have just finished K2 s/n 3093, including the KPA100.  It appears that the 
internal power meters (both the one on the K2 motherboard and the one on the 
KPA100) incorrectly indicate a higher power than actual on the higher bands. 
  I suspected that my external measurements were too low at higher 
frequencies, but I seem to be seeing the same effect when I measure power 
with my oscilloscope.  Examples:

K2 without KPA100:
band        K2 reading       Ext power reading
160m        10.5w            11.4w
10m         7.0w             5.9w

K2 with KPA100:
band        K2 reading       Ext power reading
160m        21w              22w
15m         19w              14.7w
10m         20w              14w

I will try to borrow a power meter of known accuracy, but I was wondering if 
this sort of thing has been observed before.  If not, and since it seems to 
happen with both power measurement circuits, I will suspect that both my 
external power meter and my oscilloscope are dropping off at high frequency. 
  Thanks.

Joe Borrello, W8UH





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