Path: utzoo!attcan!telly!lethe!torsqnt!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!rutgers!cmcl2!lanl!opus!ted From: ted@nmsu.edu (Ted Dunning) Newsgroups: comp.dsp Subject: Re: New cheap 200 kHz 14-bit dual ADC chip = digital HF receiver? Message-ID: Date: 22 Sep 89 17:01:52 GMT References: <1989Sep21.162329.2416@mentor.com> Sender: news@nmsu.edu Organization: NMSU Computer Science Lines: 27 In-reply-to: mbutts@mentor.com's message of 21 Sep 89 16:23:29 GMT In article <1989Sep21.162329.2416@mentor.com> mbutts@mentor.com (Mike Butts) writes: Here's something I recently posted to rec.ham-radio: ... I wonder if any DSP radio experts out there can comment on whether this chip, with an 80 kHz or so IF front end on the input and a DSP on the output might make a practical HF receiver, using the DSP for most of the selectivity, gain control, and demodulation? Is it reasonable to use that low an IF? Could you use both ADCs on the chip to alternatively sample a higher IF, like 160 kHz? if you are already down to an if < 200 KHz, then you have either done most of the work of getting the selectivity you want, or you haven't. similarly, gain control must be done earlier. demodulation can be done digitally (certainly for fm), but there may well be better digital demodulation methods than just digitizing and then (ds) processing -- ted@nmsu.edu Most of all, he loved the fall when the cottonwoods leaves turned gold and floated down the trout streams under the clear blue windswept skies.