[Elecraft] K3/100 input voltage and TX IMD

[Paul Christensen]

> With respect Don, it is already limited :)  It is limited to 120W.  What
> is the point of doing that if the radio should not be used at that power?

I can't speak for the K3 designer(s), but not all modes elevate or produce 
IM at the upper end of the output power curve.  CW is one such mode, 
although other non-IM artifacts may be possible above 100W.

There are times when driving a low-gain, GG amplifier (e.g., 3CX1200 w/ 
untuned input) when the operator wants to drive it to its maximum capability 
but in order to do so, something a bit more than 100W is required.  It's not 
worth getting into a discussion as to whether the added power increase from 
the extra drive is worth it -- but some ops want to utilize their amps to 
the fullest capability when conditions permit.

But that same op needs to understand that in IMD-generating modes like SSB, 
the K3's power needs to be throttled back to specified limits.  When running 
an amp, s/he may safely achieve 1500W in CW, but must then settle for 
something less (e.g., 1300W) in SSB mode.

Paul, W9AC