Here is my method to generate an XTAL 1 suitable output, using a Pierce Oscillator....What they use in chips.
I may try a RC network next....
Feel free to add your own comments.
A second way to generate 16MHz XTAL 1 suitable output....
Surely you all would know what is happening here....
And because its Bar Sport....
Overclocking the ATmega32A to 64MHz yields a strange result....You might think it runs 4 times faster, but no it doesn't.....
suspense..............
It erases the chip (except for Optiboot) then blinks the LED like it would do if you had just uploaded the bootloader via ISP! 
Another thing observed....don't try to upload programs at the wrong crystal speed, it bricks the chip....requiring a bootloader upload. 
A nice feature but not advised is the chip pause function....Pull the Stop pin to GND on the Pierce oscillator and presto chip stops.... 
Does that actually work with an 'LS' series IC?
Well....The NAND gate is a HC and the XOR is a LS.
Thanks for the correction, the other NAND gate I have just has 7400....don't know if that is LS.
EDIT: 7400 is worse then 74LS00.
It looks pretty old, and all it does is just gets warm.
I could understand if it didn't work being different chip structure.
I have no 74LS00 sorry, you can test it for me if you want....
What it does if you use plain old TTL chips, 74xx, and even 74LSxx chips is that it hammers the crystal and reduces the life of it. The HC and HCT put the crystal under much less strain.
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Hi,
As you are only using some of the gates in the IC package.
It is common practice to gnd the inputs of the unused gates.
Tom.. 
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Yes, I know I should....but I don't even have the decoupling capacitors like the schematic says on the chips. Shhhhh.
I probably should include a 1K resistor to prevent that happening.
Here is all the XTAL suitable sources I've tested....I can't guarantee they will all work for anyone else....All have passed the upload test with a ATmega32A.
And yes, I know decoupling caps should be included on the 74xxxx chips, I saw the noise on the oscilloscope....The ATmega32A has them however.
P.S. Sorry for the strange chips....Some KiCAD error.
I just realized that LS & HC etc. can't do above 20MHz IIRC....I should acquire some 74ACxx series chips.
Yes or some 74Fxx chips or ALVC
This is most of the chip types in the 74 series:-
From this PDF:-
http://focus.ti.com/lit/ug/sced006b/sced006b.pdf
Also there is ECL logic chips (Emitter Coupled Logic) for very fast speeds.
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Well I've managed to get 40MHz out of the LS XOR gate....I've grounded the other inputs per @TomGeorge's suggestion, plus I noticed it affected speed....
I ran the test using a AVR128DA28 chip....upload completed with zero errors, 48MHz was too much however.
I am waiting for my AC & F parts....
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