I have a small handful of crystals and was wondering what the easiest way to divine their frequencies... I can say that I'm reasonably certain that all of them are between 32.768Khz and 50MHz, but some are blank, and some have non-obvious cryptic markings. What I'm looking for is some simple way to get them to oscillate and measure them with a frequency counter (i.e. - assume one is starting with a working, trustable frequency counter). Is it as simple as a pair of inverters/NANDs in the classic crystal loop, or is that circuit massively frequency dependent (i.e. - works for 1Mhz-10Mhz, not faster or slower...)? Thanks for any suggestions. -ethan