Minecraft Forums

Updated for 1.7.2. Just showing how I did it. There are other ways, but this worked for me:

I followed your instructions to the letter and managed to get it working, good tutorial. Any idea how to make a door that's 3 blocks tall instead of 2?

You can power the middle blocks the same, the side blocks need a different method. And the bottom middle block need to be powered from underneath. Hope that helps.