> Even if it is not real time, it would be nice to have a
> 1.8..30MHz analyzer. If each 192 kHz band is captured for 2
> seconds (to make the Si570 loud click to dissipate), a full sweep
> will take about 5 minutes. Much faster if only some bands are
> It would be difficult to calibrate and make it into a real
> instrument because of the uneven BPF gain, central peak and other
> issues. Yet, for the price it would be great value, allowing
> continuous monitoring of the entire HF.
I already do something like this, but is only to watch what is going on
over more spectrum than I can see at once.
No idea about the Si570 (and what is talking to it), but with FCDP+ I
can have SDR# (with N8GJL's scanner plug-in) hang around for ~100 mS as
it scans between memory channels. At 196 kc, it takes 7 memories to
cover, for example, all of 20, 17, 15 & 12m.
The result is four bands sharing the same waterfall - looking a bit like
vidiplex gone berserk - is adequate for the monitoring I do (have
learned how to work with it), but what would really be neat would be to
have separate displays/waterfalls for each memory channel.
Being able to see more spectrum than is already presented pretty much as
it is by a spec-an to me is what is required for either spectrum
"monitoring" or "analysis" applications - within the limits of the
receiver/sampling used (therefore dynamic range, resolution, etc),
everybody already has a basic spec-an if they use a SDR. ;^)
> --- In email@example.com, <firstname.lastname@example.org> wrote:
> ----- Original Message -----
> Subject: [softrock40] I Have a Question.
>> > Is there nay chance that there could be a spectrum analyzermade from
>> the Si570 chip?
>> > I would be nice to have something like that that would be affordable
>> for amateur use. Most spectrum analyzers are quite expensive
>> > and it seems that the Si570 chip could be put to use for that
>> considering that it would be a receive only item. Just thought I
>> would ask.
> If that Si570 is built into a Softrock and used with something
> like HDSDR it is a spectrum analyser.
> t> >
> Optimised for a high-end soundcard it could enable relative
> measurements over a span of 190KHz and a range in excess of
> Nothing to do with Si570s or Softrocks, a RTL dongle could show a
> span of 2MHz but with a range of just up to 60dB. Other SDRs are
> available with varying specs and frequency ranges.
> 73 Alan G4ZFQ