[Elecraft] K3: 630m amplifiers

[Fausto Coletti]

It depends on how you made the amplifier.
I produce some models of amplifiers, of different powers, all in switching 
operation.
Here an image of the DK7FC grabber, you can see at 472.1 KHz the 
spectrogram of
a German station that use a class D amplifier, at 472.5 an Italian station 
that use a 400W
tube linear amplifier and at 473.3 there is my signal with my QRO+ switching 
PA. 

https://www.dropbox.com/s/oziocm3vshfftgl/19012015.JPG?dl=0 

I can assure that I often find local stations operating at 250-300 Hz from 
my frequency
that are not minimally disturbed
I do not think that a linear amplifier is so better.
I also made a 100W output amplifier specifically designed for the K3.
This amplifier runs at 12 volt.
All my PA need an input signal (adjustable) from -10dBm to + 20 dBm 

https://www.dropbox.com/s/u2yjp0ltv0kbsy5/K3%20and%20Pa.jpg?dl=0

73, Fausto IK4NMF