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I have a 4Mhz (YIC 4.000006 ) crystal. I would like to generate a simple square or sine wave (whichever requires the least components), only for learning purposes, no practical use. I want to be able to see the output on a oscilloscope.

I can't seem to find any tutorials that explain how the crystal is connected/works. I believe I'm using the wrong search terms. Whenever I search for a 'crystal oscillator' I get results of complex schematics (I'm a beginner), but I'm looking for the most primitive way to get some kind of output out of the crystal as I'm trying to learn how it works, but now I'm completely clueless on how to even connect it.

What is the most primitive way using only the standard components to generate any kind of pulse/wave/output from the crystal, so I could pick it up using an oscilloscope? Thanks!

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Can't get much simpler than an inverter crystal oscillator:

enter image description here

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  • \$\begingroup\$ Can this be done without the inverter? The inverter is used as a logic two logic gates? Sorry I'm not familiar with this component as well \$\endgroup\$ – 0x29a Jan 12 '17 at 23:54
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    \$\begingroup\$ To create an oscillator you need an active device with gain. This is a single simple digital inverter as the gain element. The output invertor is simply to buffer the signal. If you don't know what digital logic is, then you have a more fundamental problem that requires some study. You could start here: ww1.microchip.com/downloads/en/AppNotes/00826a.pdf though this may be too advanced. \$\endgroup\$ – Jack Creasey Jan 13 '17 at 0:11
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    \$\begingroup\$ @0x29a, as Jack Creasey says, you need a powered circuit and the inverter circuit is a pretty simple one to try. You can get all the parts, and some Veroboard or a breadboard to hold it all, from a high street supplier. Unfortunately, the crystal alone is just a part of the oscillator. Good luck and don't be afraid to have a go :-) \$\endgroup\$ – TonyM Jan 13 '17 at 0:15
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    \$\begingroup\$ @JackCreasey wouldn't it be better with a Non Schmitt trigger for XO, otherwise it oscillates at relaxation rate of 2/Rf*C \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Jan 13 '17 at 1:17
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    \$\begingroup\$ i.e. your schematic shows 2 inverters , but the 1st cannot behave properly with hysteresis. and the 2nd is not necessary to have it either. pls correct schema. \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Jan 13 '17 at 1:37
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Connect a fast Trise Tfall squarewave generator, frequency at 1MHz or 0.1MHz to one pin of your crystal, and other crystal pin to your scope probe.

How fast a Trise? faster than 1/4 of period of 4MHz , thus faster than 100nanoSecond.

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  • \$\begingroup\$ The OP wanted to use the most primitive means, to see a waveform on the scope. This allows that viewing. \$\endgroup\$ – analogsystemsrf May 26 '17 at 15:13

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