Invisible Redstone source for mapmaking or lock a redstone component

What about adding a block a bit like the light block, invisible to all, that we can pass through, ... But instead of giving light, it could gives a redstone signal so we don't have to setup a system to place and remove a redstone block every tick so it's not visible?

The exemple I have is:

I have placed a lever and behind the block the lever is on is an iron trapdoor. So it will open and close when we de/activate the lever, but I want it to be closed everytime because it's for decoration purpose.

If not, just being able to lock a redstone component phase so it will not change state!