[Elecraft] K3 & ADAT ADT-200A by HB9CBU

[Bill Tippett]

Phil and Chen,

Thanks!  I thought it looked like crystal filter performance but was
thinking it was synthesized.  This looks like a much better system
than Flex's QSD.  I wonder how long it will be before Flex goes to the
same system?  Phase noise and BDR have been Flex's weak links IMHO.

I just located the Perseus user manual so will do some reading on it.
For anyone interested:

http://microtelecom.it/perseus/perseususermanual-en12.pdf

73,  Bill

On Thu, Dec 4, 2008 at 3:30 PM, Kok Chen <chen at mac.com> wrote:
>
> On Dec 4, 2008, at 11:23 AM, Bill W4ZV wrote:
>
>> Have you described how you achieved this somewhere?
>
>
> Bill,
>
> I suspect it is because there is no synthesizer in his receiver.  Everything
> comes off of a single crystal, and as you decimate, the noise from the
> oscillator becomes even narrower.
>
> All the other "oscillators" are numerical and can be made as noise free as
> there are processor cycles.  Even in cocoaModem (2.4 kc passband digital
> mode stuff for the Mac OS X), I had use a 24 bit since/cosine generator,
> using 12-bit table lookups and the double angle trig formula to get 24 bits
> of output resolution.
>
> "Phase noise" is a hardware artifact :-) :-)
>
> Vy 73
> Chen, W7AY
>
>