01-01-2017, 11:00 AM
Yes, as Lawrence says, your 40MHz crystal is actually a 13.333MHz third overtone crystal. In normal operation you would have a resonant circuit tuned to 40MHz on the output.
The 3rd harmonic of 3.2768 is 9.8304MHz which doesn't agree with your reading so I wonder if the crystal is trying to operate in the wrong mode. Perhaps you should try it in a different circuit.
I'm fascinated by the idea of a 21.8MHz pantry transmitter - what, exactly, were you planning to use it for?
The 3rd harmonic of 3.2768 is 9.8304MHz which doesn't agree with your reading so I wonder if the crystal is trying to operate in the wrong mode. Perhaps you should try it in a different circuit.
I'm fascinated by the idea of a 21.8MHz pantry transmitter - what, exactly, were you planning to use it for?
