[hpsdr] Odissey QSD circuit diagram

[Philip Covington]

On 9/29/06, Jim Miller <jim at jtmiller.com> wrote:
> I was looking at Phil's circuit and can't figure out something. IIRC, in
> order for the integrator summing junction to function the signals applied
> need to be within the loopgain of the integrator.
>
> The signals applied to the integrator are the sum and difference freqs (and
> harmonics) of the received signal and the vfo.
>
> I don't see how the sum frequencies are handled by the integrator since they
> exceed the available loop gain. Are they merely passed through to the
> passive filter that is behind the opa1632?
>
> If so how then does this act to maintain the proper impedence mentioned
> below?
>
> tnx
> jim ab3cv

My circuit does not use a OPA1632 in the active integrator.

Phil N8VB

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