and I've tried hooking a crystal to the F_in point in the second schematic, leading it directly to an input on the 74HC14. I'm using 74HCT14, but I don't think that this will be the problem that I can not get any reading out.
The other lead of the crystal is connected to ground. Maybe I'm doing something wrong ? In the picture the guy is measuring a frequency off a crystal, I'm aiming to do the same.
My best guess is that your crystal isn't oscillating - what speed is the crystal supposed to be (its best when testing a circuit like this to use a known speed device that you know is working)? The author does note that 8 MHz is about the maximum input frequency - if your crystal is working, and is greater than 8 MHz, that could be the issue...?
The thing about his circuit (his breadboard/protoboard) is that on the board are two caps, but the actual circuit only shows a singular cap. Now, he could be using those in parallel or something to get the proper size shown on the schematic, but it isn't clear. Also, I wonder where the loading capacitors are (or are those the ones shown, and if so, where is the one in the schematic then?); most crystal oscillator circuits I have seen (I am not an expert, keep that in mind) have a couple of smallish capacitors (18-22pF, IIRC) on each leg of the crystal, leading to ground (once again, IIRC).
I have several crystals below the 8 MHz threshold. and none of them are showing any results. The capacitor there is I think just to filter the supply to the IC, I've tried it with the cap and without the cap, nothing seems to be doing anything.
Now the problem is that on the serial output I'm getting random number that aren't even close to the xtals's real frequency. Even when I only hold a wire connected to pin 5 it displays random data.