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Cefiar
Problem with the 74HCT and 74ACT parts is that they're 5V logic only from what I have read (they're +5V with +/-0.5V supply), and 3.3V won't register as a logic "High".
If someone can point me to anything that says different, I'm happy to concede the point. This was based entirely on a 10 second Google search and looking at 2 spec sheets.
I spent a while looking at this trying to work out the best parts to use in any particular combination of input, output, supply... it's pretty complicated! There is a useful summary chart here [www.interfacebus.com]
For HCT/ACT, they need a 5V supply BUT will accept 3.3V or 5V logic level inputs.
For HC/AC they can use a 3.3V or 5V supply, BUT at 5V they are NOT compatible with 3.3V inputs. (In practice it may work, but can't rely on it).