Re: [Discuss-gnuradio] Direct Conversion vs Superheterodyne

[Nick Waterman]

Ettus, Matt wrote:
> I've got a bone to pick with Mr. Tayloe.  He didn't invent that.  Its been
> around for about 30+ years.  Its called a commutating mixer, differential
> quadrature switched mixer, or multi phase sampler.  It is a nice easy
> circuit, though.

Cool, fair 'nuff, I'll do some websearches for them and hope they 
produce more cool info than I've found on "Tayloe Detectors"  :-)

> As someone who works every day on direct conversion receivers every day, I
> have to say that they are not as easy as people say, unless you don't care
> about the DC content of the signal.  If that is the case, then you're not
> really using Direct conversion anyway, you're doing low-if.
[snip]
> Just because you have only one conversion, and do everythign else digitally
> doesn't make it direct conversion.  If you convert the carrier down to a
> frequency other than 0, it is a low-if receiver.

Well... True... Moreorless... But when you're listening to morse, you 
never tune it to DC and listen to the clicks, do you? You stick it 
somewhere nice like around 500Hz and listen to the beeps. Same with 
almost anything except AM really

So call it a downconverter rather than a direct conversion receiver if 
you prefer. We're sort of doing the real "receiving" in software anyway, 
right?.   :-)

> Gerald Youngblood, the author of that article, has since stopped calling it
> a Tayloe detector, since it isn't a Tayloe Detector any more than it is an
> Ettus Detector or a Waterman Detector.

Cool, might explain why I couldn't find anything NEW about it. I shall 
stop giving Dan so much credit too then. In the meantime, it's supposed 
to be secret - who told you about the Waterman Detector?!?!?   ;-)

--
"Nosey" Nick Waterman, Senior Sysadmin.  #include <stddisclaimer>
address@hidden  http://noseynick.net/
Just remember...if the world didn't suck, we'd all fall off.