I've gotten my TTL clock all working on my solderless breadboard and I'm thrilled about that. All built from flea market or scrounged parts. It draws a little more that 500ma according to my bench supply at 5v. I got a 9v dc 1000ma wall wart to use as a power supply (It actually reads 12v without load) hooked to a 7805 regulator with caps to make the 5v. Everything works fine, but the 7805 is pretty hot. I have a heatsink on it so I guess it will run but I am concerned about the heat especially when I put it into an enclosure. If I got a lower voltage wall wart, say 7v, would the 7805 run cooler? Any other suggestions. Thanks.