Minecraft Redstone – How to Lengthen a Redstone Button Signal

If you watch at about 2:50, you can see most of the left half of the circuit. The part for the stairs looks like it isn't shown very well but that is less important timing wise. Watch carefully over and over and see if you can replicate it this way. It looks like the repeaters for the middle activate and deactivate immediately. So the order (from a circuit standpoint) for both directions is M, L+R. This works for closing because the middle repeaters don't have anything to activate until the blocks are pushed into the middle. When opening, they will retract the middle immediately.

Breaking it down:

Opening

1. Middle repeaters deactivate (middle pistons retract)
2. Delay
3. Left and Right redstones deactivate (left and right pistons retract)

Closing

1. Middle repeaters activate (nothing happens because the middle pistons are not in position)
2. Delay
3. Left and Right redstones activate (left and right pistons extend)
4. Now the middle pistons have been pushed into position and are activated by the middle repeaters

Redstone state is not saved when a chunk unloads, however entity state is. This means minecarts will continue to move when a chunk is reloaded. This in turn means if you replace your redstone clock generators with minecart based clock generators, they'll resume ticking when a chunk is reloaded. Here's the most basic Minecart ticker:

You can adjust the lengths of track to get the length of tick you require, and you can combine with other tickers outputs ANDed together to fine tune the length of the tick.