[time-nuts] Re: DIY Low offset Phase Noise Analyzer

[Leon Pavlovic]

I've tried to do a simple and low-cost sound-card PN system too back in the
days. It's fun, when you see the broadband thermal resistor noise in your
FFT plots :) But when doing experiments with the crystal oscillators, I've
found out that one of the *MOST* important things to worry about is
injection locking, especially if you do OCXOs and very low PN oscillators.

Before feeding the RF and LO ports of the mixer, you should have isolation
amps on both ports with about or more than 100dB S12 isolation, not to get
into trouble. Without them, you'll be measuring unreal PN noise...

Cheers,
Leon