[Elecraft] Tr: K3 Ref connector

[Wes Stewart]

--- On Sun, 5/17/09, Brendan Minish <ei6iz.brendan at gmail.com> wrote:

> From: Brendan Minish <ei6iz.brendan at gmail.com>
> Subject: Re: [Elecraft] Tr: K3 Ref connector
> To: "David Pratt" <david at g4dmp.fsnet.co.uk>
> Cc: elecraft at mailman.qth.net, "Dave G4AON" <elecraft at astromag.co.uk>
> Date: Sunday, May 17, 2009, 6:44 AM
> On Sat, 2009-05-16 at 08:03 +0100,
> David Pratt wrote:
> > The connector is referred to on page 17 of the latest
> K3 Owner's Manual 
> > and my K3 rear panel is labelled "REF."
> > 
> > In consequence, I have bought a Racal-Dana 9474
> Rubidium Frequency 
> > Standard which is now poised to plug in as soon as the
> KREF3-EXT is 
> > available, hopefully quite soon.
> 
> Couple of thoughts here 
> 
> Unlike the Racal RA3702 I have here; the K3 is incapable of
> phase
> accuracy (RF to audio), or indeed exact frequency accuracy
> (multiple DDS
> LO conversions with ensuing decimation errors, varying
> offsets for
> roofing filter positioning etc)     

Correct. I have been able to hear, or more easily see using Spectrum Lab, the change in pitch on a signal while simply changing the DSP bandwidth.

There is a lot of frequency changing going on when the passband is moved and not every oscillator moves at the same rate.

Best have another receiver around for the FMT.

Wes  N7WS