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Dennis,

That is a fantastic presentation! Thank you!

When I looked at Andrew Holme's design, my first thought was to do as much of the signal processing in the analog domain as possible. Dynamic range is much more expensive in the digital domain.

Fundamentally, it doesn't matter if the work is done in the analog or digital domain if they are done correctly. Unfortunately, my observation is that digital is often very poorly implemented.

My most recent technical binge was on low noise xtal oscillator design. At present this includes:

Electronic Noise and Low Noise Design
Peter Fish

Low Noise Electronic Design
Motchenbacher & Fitchen

Understanding Quartz Crystals and Oscillators
Cerda

Crystal Oscillator Design and Temperature Compensation
Frerking

Intermodulation Distortion in Microwave and Wireless Circuits
Pedro & Carvalho

If anyone knows of other monographs on the subjects please post them.

The conclusion I drew from my reading was that the first task is to design a low noise amplifier. The second task is to minimize the intermodulation noise. The latter is most easily done by filtering the input to eliminate harmonic content. In particular, mixing of the 2nd and 3rd harmonics produces a baseband component which degrades the phase noise level at baseband. Filtering *before* the amplifier prevents that from happening.

It occurs to me that a set of series resonant harmonic shunts in the feedback loop of an xtal oscillator might have the effect of reducing the phase noise. Does anyone know of prior work? I'm sure there's a lot.

Investigation in earnest once my new lab is built.

Have Fun!
Reg