05-01-2017, 08:26 PM
(This post was last modified: 05-01-2017, 08:33 PM by Murphyv310.)
(05-01-2017, 12:54 PM)Crackle Wrote: What I want to understand is how to get the crystals to give out lower harmonics, so that they can be used as the manufacturer intended.
Mike
Mike.
The manufacturer would never use lower harmonics. A third overtone crystal is basically the third harmonic up.... of the fundamental or what the crystal is cut to.... never below.
If you Google "Crystal oscillator Sub harmonics" you should get plenty of info. I already stated that sub harmonics are very low indeed and in fact not a desirable phenomenon. They often are caused by the inaccuracies of manufacture. If you have a crystal with say for arguments sake 5 MHz it should oscillate at that frequency, you should be able to check it with a frequency counter without any tuning, conversely a crystal marked 15 MHz which is a third overtone 5 MHz crystal, will require a bandpass 15 MHz tuned circuit to operate correctly.
There is something massively amiss in your tests Mike as they don't make any logical sense. Mind crystals can be ruined by excess voltage across them unless they are specifically designed for that scenario.
