I've build a circuit exactly like the one below except Im using a SN74HC14N (schmitt triggered inverter).

https://i.sstatic.net/m0kfI.gif

The output of the circuit looks like this, however isnt it supposed to be more square wave looking? I've tried feeding the output to another schmitt triggered not gate but the output stays the same. Anyway to get a more square wave looking output?

Also when I used non schmitt triggered not gates there was no output at all. All the gates im using are TTL. The crystal is 8mhz, and my oscilloscope goes up to 100mhz

https://i.sstatic.net/nLnWy.jpg

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