Hi, I am making a multi floor bubble elevator and i want some help. I want the piston in the folliwng image to be normally extenderd and when i right click the note block to reatract briefly ( I have set the pulse i just need help to make piston normally extended and when i powered it with redstone to retract. where the green cocncrete blocks are I don't want any redstone. Thanks!
Right-clicking a noteblock (which tunes it) is not supposed to be/not listed as detectable.
Swapping in a fencegate (the state change of which an observer will detect) reveals that the unmodified output from an observer is too short to pulse a RS-torch and must be extended to last at least two RS-ticks.
A redstone torch takes 1 redstone tick (2 game ticks, or 0.1 seconds barring lag) to change state and won't change state unless the signal change to its attachment block is at least 1.5 redstone ticks long (unless the change is caused by the redstone torch itself in a "short-circuit"). For example, a redstone torch won't turn off if its attachment block receives a 1-tick or shorter pulse.
Is that a repeater on the floor for the output? If so an upward facing sticky piston on the floor below your piston and a redstone block should do the trick. The one tick pulse from the observer will cause the piston to alternately pickup and drop the redstone block. When its in contact with your piston it powers it. If you can't get an output from the noteblock (never tired it myself) then a trapdoor/gate/door or various other items can be used. You can decide the default state for your piston (extended or not) from there.