I read in sci.electronics.design that douglas dwyer
wrote (in )
about 'Using non-overtone crystal in overtone mode?', on Mon, 28 Feb
2005:
Overtone crystals are mechanical resonators and the overtone shear mode
which has additional shear planes within the volume wont occupy exactly
the same volume as the fundamental so the frequency will not be exactly
3X or 5X the fundamental but approx 2000ppm high or low?

I remember being told by a crystal 'expert' that with some cuts the
difference can be much larger than that. Is that so?
--
Regards, John Woodgate, OOO - Own Opinions Only.
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk