Why is my sticky piston not extending?

In a 1.15.2 java server, I want to use this design for a timed bubble elevator, but the sticky piston is not extending. Everything powers up as it should, except the piston.

Any ideas?

Solution 1:

Your piston is not receiving direct redstone power: Notice how the redstone wire is pointed away from the piston. In order to power that piston, you'll need to either power a block directly adjacent to the piston, or loop your wire around slightly so that it points directly at the piston.

One thing you can do is bring that wire up 1 block: place a block next to the repeater with a piece of redstone on it, and another block directly behind the piston. This should give your piston direct power, allowing this design to work.