On Fri, 2006-11-10 at 18:44 -0500, michael taylor wrote:
The bigger limitation, in terms of flexibility, is “Worldwide FM band
support (76â€“108 MHz)” from their Features page of the Si470x single
chip FM receiver. I don’t see the interest, it is a FM-only receiver
basically with the broadcast band (worldwide).
Well, it’s been interesting enough for people to be selling $50 FM Radio
dongles by the bucketful
The 96Ksps over USB is
irrelevant given the “IF” (output from the Si470x) signal is being
(lowpass) filtered at 23 KHz.
But since the original audio was only 15 KHz, you could lowpass filter
at the 96 Ksps rate and then decimate by three, increasing the effective
dynamic range above 10 bits. But see below…
You could add it to gnuradio, but it
would be for novelty’s sake only, as you cannot make use of GNU
Radio’s DSP features other than just with the audio output.
That’s the real limitation, to be sure. In fact, the USB controller
shows up as a Windows sound card, so you could use these with the
existing audio drivers and some fiddling for control. As the original
poster wondered, it would be far more useful to get downconverted I/Q
out of the thing. This would be great, for example, if someone ever
gets around to implementing an IBOC decoder for HD Radio.
Johnathan C., AE6HO
Corgan Enterprises LLC