[Skimmertalk] Monitored Frequencies vs. Displayed Frequencies

[Edward Russell]

The SDR-IQ "local oscillator" or center frequency is set by Skimmer through
the ActiveX. Then Skimmer internally sets the "tune-at" or demod frequency.
Neither the SDR-IQ or the ActiveX aware of the demod frequency.

73 Ed W2RF

> -----Original Message-----
> From: skimmertalk-bounces at contesting.com [mailto:skimmertalk-
> bounces at contesting.com] On Behalf Of Pete Smith
> Sent: Monday, February 02, 2009 4:53 PM
> To: W3OA; skimmertalk at contesting.com
> Subject: Re: [Skimmertalk] Monitored Frequencies vs. Displayed Frequencies
> 
> Yes, this is right, and is a good point.  The problem is not inherent to
> the SDR-IQ, though -- the Spectravue bandscope application has separate
> center and demod frequencies.  Maybe we just need to encourage Alex and
> Ed,
> W2RF (who wrote the Active-X control that links the SDR-IQ and Skimmer to
> provide the same flexibility for Skimmer (if Skimmer's architecture
> doesn't
> effectively prohibit such a change).
> 
> 73, Pete N4ZR
> 
> At 04:13 PM 2/2/2009, W3OA wrote:
> >This points out what, I think, is an advantages of using SoftRock Radios
> >with Skimmer.  The local oscillator frequency  and the "Tune at
> >Frequency" are specified individually.  So changing the "Tune at
> >Frequency" doesn't change the portion of the band Skimmer is decoding
> >signals in.
> >
> >At least I think that's how it works.
> >
> >73 - Dick, W3OA
> >
> >skimmertalk-request at contesting.com wrote:
> > >
> > > Message: 1
> > > Date: Mon, 2 Feb 2009 07:29:05 -0500
> > > From: "Jeff Maass" <jmaass at k8nd.com>
> > > Subject: [Skimmertalk] Monitored Frequencies vs. Displayed Frequencies
> > > To: <skimmertalk at contesting.com>
> > > Message-ID: <005901c98531$d7913800$020aa8c0 at Maass99>
> > > Content-Type: text/plain;     charset="us-ascii"
> > >
> > >
> > > I am constantly annoyed by the inability to look at sections of the
> > band away from the
> > > "Tune at Frequency".
> > >
> > > I'd like to be able to check visually the activity across the
> monitored
> > bandwidth without
> > > changing the "Tune at Frequency. The green "bumper stops" as I drag
> the
> > visual display to
> > > change frequencies displayed are my least favorite "feature" of CW
> Skimmer.
> > >
> > > Let me see if all my assumptions are correct.
> > >
> > > My assumptions:
> > >
> > > 0. I use SDR-IQ receivers with CW Skimmer. I have
> > >     them set for "96 KHz" sampling rate.
> > >
> > > 1. This is going to sample a bit less than 96 KHz
> > >     of the band;
> > >
> > > 2. The *center* of the sampled band segment is set
> > >      in CW Skimmer by setting the "Tune at
> > >      Frequency".
> > >
> > > 3. The "Tune at Frequency" also sets the point at
> > >     which I can listen to a CW signal on the band.
> > >     If I click on another signal displayed in the
> > >     ~11 KHz displayed on my screen (may vary with
> > >     screen resolution), it changes the "Tune at
> > >     Frequency" to that frequency, and so changes
> > >     the center of the monitored band segment.
> > >
> > > I would like be able to set the center frequency independent of the
> > frequency range I am
> > > viewing or the frequency I am listening to.
> > >
> > > Is this possible? Has anyone proposed this to Alex, or am I just
> > completely off-base in my
> > > understanding of CW Skimmer and the SDR-IQ receiver?
> > >
> > > BTW, CW Skimmer was **invaluable** at PJ2T during the CQWW 160 CW
> > Contest! Our DSL crashed
> > > on the first night, and Skimmer (connected to our switchable receive
> > antennas system)
> > > provided us with several "pop-up multipliers" that we might have
> > otherwise missed. We will
> > > (likely) be in 3rd Place Multi-op Worldwide (after Africans CN3A and
> > CT9M) when all the
> > > dust settles.
> > >
> > >
> > > 73,  Jeff  K8ND
> > >
> > >
> > >
> > >
> >
> >_______________________________________________
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> 
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