Juan:

We are using a quadrature sampling mixer at 10.7 MHz IF. Consider it a roofing filter and mixer in one simple package. We will set the bandwidth appropriately. If the impedance is matched to the output of the receiver, it will have very large rejection anywhere outside of the passband of the receiver. The A/D will operate at D.C. and not at 10.7 MHz if.

Bob

Juan Rivera wrote:

All,

I'm not trying to beat this to death but I want to make sure I fully understand what I'm looking at here...

I spent some time this evening looking at the spectrum between the 10.7 MHz IF output and zero Hertz. I did this because I believe it may be a significant area of interest since the receiver will feed an analog to digital converter. The A/D converte

r is not a tuned stage so it will

digitize baseband noise along with the IF signal. I've been told that the impact of noise in the baseband is to reduce the dynamic range in the digital domain. I'd appreciate an explanation since I am woefully ignorant in this area.

I posted my results in the usual area. Just scroll down till you come to today's date.

73,

Juan

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