[Elecraft] Unique synthesizer LO ?

[John, KI6WX]

Peter;
I have posted on the web a detailed set of measurements of the K2 phase 
noise, both in receive and transmit.  The measurements cover a frequency 
range of 20 Hz to 45 kHz.  These measurements can be viewed at:

http://home.pacbell.net/johngreb/k2phasenoise.pdf

The ARRL composite transmit noise measurements that were published in QST 
are in errror and show less noise than reality.  The transmit phase noise 
measurements in the above document are the correct phase noise measurements, 
but they do not include any amplitude noise that might be on the transmit 
carrier.

The K2 oscillator phase noise is good for a simple low-current synthesizer, 
but there are ways to make it better.  I note some of those in the above 
document.  A re-designed K2 RF board could drop the phase noise by at least 
10 dB, which would improve the 5 kHz two-tone third-order dynamic range 6 
dB.
-John
 KI6WX


> Maybe not the cleverest question of the year but I cannot resolve this one
> myself and I'm eager to understand.
>
> It is said that the synthesized LO of the K2 is of a unique design.
> Though, when I compare the LO phase noise specs of the K2 and the AOR7030,
> the latter seems to show much better specs.
>
> What makes the K2 synthesizer so special ?
> I'd appreciate any comment.
>
> Peter, PE1E