[Elecraft] KX1 lower power only on 40?

[Rick Dwight]

Dan,
  If you tested your KX1 into a good 50 ohm dummy load, the indicated power
should have been within 10 or 20% of the correct power either with the KX1
in Cal, or in Tune if you do an ATU tune.
  If you tested it into a resonant 50 ohm antenna, then the reading should
also be correct on that band.
  If you test it into a random wire and counterpoise, then the power reading
will only be approximately correct if the ATU can tune it to something like
< 1.5:1 on bands you measure.  If the ATU can only tune it to say an SWR of
2:1 or 3:1 or higher, then the power reading may be way off....possibly by
more than 50 %.  
  The ATU has a very limited tuning range on 80 meters, so a resonant
antenna or only very specific lengths of wire and counterpoises can be
tuned.  However certain lengths of wires can usually be tuned on 40, 30, and
20 meters.  For example a 26 ft wire antenna with a 17 ft counterpoise
laying on the ground will usually tune to well below 2:1 (typically < 1.5:1)
on 40, 30, and 20 meters.
   I always try and only use antennas which the ATU can tune to < 2:1 SWR,
although at times I have pushed this to 3:1 without problems after about 10
years and thousands of QSO's.  
   My suggestion is to buy or build a 50 ohm dummy load as your first piece
of test equipment.
   Good Luck      Rick   KL7CW  
   
  
   



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