alt Hacker NewsThat’s why you probably want to use it in an oscillator rather than a filter. Then some of those problems go away. Although, some new ones appear like having to add a mixer … Some time ago I thought making a double superhet would be too complex but apparently it turned out quite a nice DYI project.
One of the problems I'm struggling with is that I'm trying to recover a signal with a known pattern from under the noise floor and every little bit helps. Varicaps will come into play once there is enough signal that the thermal noise and power supply influence would no longer drown out the signal. Interesting project but it is one of those where when you start you think 'how hard could this be?' only to find out that it is in fact pretty hard. We'll see if I can pull this off or not, I give it 10% chance at the moment.
Oh, and superhet wouldn't work, that would destroy the valuable part of the signal.