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Old July 17th 10, 05:37 AM posted to rec.radio.amateur.homebrew
Graeme Zimmer Graeme Zimmer is offline
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First recorded activity by RadioBanter: Apr 2010
Posts: 9
Default direct conversion receiver Question

Hi Jack,

Looking at yours and the simple block diagram I am curious about how this
differs from quadrature processing.


I'm not sure I understand your question.

As the diagrams show, the VFO is divided by four to produce 90deg quadrature
LO signals which drive two mixers.The two audio channels pass through two
BPF filters, one of which has a Gilbert transform to give 90 deg delay. It's
the standard Phasing Method..

If you're asking about Binaural reception, it's the same as above, but less
the Hilbert transform so there's no sideband suppression..

Admittedly that page is somewhat condensed (simplified) over the original.

Regards .......... Zim ........ VK3GJZ