So i was talking with a mate about crystals yesterday, he has an old 2m rig chock full of pairs of repeater crystals and the discussion was about overtone and fundamentals and all that. So for shits and giggles I knocked up a test fixture to measure some crystals on the VNA. And with the best crystals I have was getting the typical plot for a crystal.
And one thing lead to another and I built another crystal filter, this time for CW. I kind of did not make my target, of 500hz and was closer to 1200hz, but that is nothing changing the values of the caps cannot fix. Ripple is nice, the best i have made yet, the shape is acceptable and the stop band is down near the noise floor of the VNA, so all in all its not a bad looking filter and should be usable once i make it narrower.




