[Elecraft] Why is KX3 phase noise so much less than the K3 ?

[Bill W2BLC]

Thank you Fred K6DGW - you are correct - I was referring to phase noise 
on RX.

So far as noise from XMIT on other rigs, I have no experience. I live in 
a rural area and have an extremely low ambient noise level. A noisy RX 
exposes itself immediately.

As I recall, the quietest rig I ever had back in the day was a TenTec 
Corsair II. However, that was over twenty five years ago and it was analog.

Of my recent type equipment, the K3 is the quietest - most likely as 
quiet as the Corsair was. Just understand, my viewpoint is from the 
armchair copy side. I do not DX or contest. The K-Line is probably 
overkill for what I use it for, however, it sure is awfully good at the 
job (just know your rig and make the appropriate menu adjustments).

My original comment/query merely was aimed at the difference in real 
world use and inside a copper lined lab.

Bill K-Line