[Elecraft] Class - A operatiom (was K3 #441 received)

[Geoffrey Mackenzie-Kennedy]

Jim  <N2EY at aol.com> wrote on Thursday, February 21, 2008 at 2:03 AM:

 > It only takes a little bit of nonlinearity to create distortion products. 
For
> example, suppose an amplifier with 100W output has enough nonlinearity to
> produce a distortion product that is 1 watt. Such an amp's distortion is 
> only
> 20dB down. To reach 40 dB down, (.01%) the distortion product would have 
> to be
> only 10 milliwatts.

Not to be forgotten are the distortion products generated by the exciter. A 
perfect distortion free linear amplifier driven by an exciter whose IMD 
products are only 30db down will produce an output with products down 30db 
approximately. A case of 'garbage in - garbage out'.

73,

Geoff
GM4ESD