Azelio Boriani wrote: > Interesting this third overtone/fundamental*3 idea but what makes the > third > overtone not equal to the fundamental*3? Is the crystal operated in series > or parallel resonance? >
That is where the special SC cut crystal comes into play. It's not so much that the 3rd OT is on a different frequency, but rather that it has a different and known tempco relative to the fundamental, so it can be used as a thermometer. It would be interesting to take a crystal out of a random 10811 and compare the frequencies of the fundamental and 3rd OT vs temperature to see if that crystal would accidentally make a good thermometer. Rick Karlquist N6RK _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
