[Elecraft] (K3) SWR Consistent - low or high power

[Randy Farmer]

It's pretty unlikely you'd see harmonic content on any kind of broadband 
power sensor like a SWR meter. Even if the transmitter was really bad 
and had harmonic levels only 40 dB down, this would mean for 100 Watts 
output you would be getting 10 mW in harmonic energy, which wouldn't 
wiggle anybody's meter very much. And if the total harmonic power at 40 
dB down was just equal to the reflected power from your antenna 
mismatch, this would mean the antenna would have a VSWR of 1.07. My 
money's on diode nonlinearities at low power levels.

73...
Randy, W8FN

On 10/10/2012 04:20, Tom Boucher wrote:
> My theory in these cases is that it's nothing to do with bad antenna connections, but more due to the rig putting out a higher harmonic content at higher power levels. The SWR meter sees a bad SWR at the harmonic frequency so the reading is slightly worse.