How do you make a ultra-compact repeating signal for dispensers?

use a piston repeater

it works on the principle that a solid block transmits power but air doesn't moving the block disrupts/establishes the signal

I use this one. It's compact, easy and fast.

    B-R>-B
    D-<R-W

    D: Dispenser
    B: Block
    R: Repeater
    W: Wire

> or <: repeater direction

This one is very compact and can shoot 20 arrows per second.

L:Lever
R:Redstone
BR:redstone on block
RT:redstone torch
D:dispenser
RP:repeater

      RT-BR-RT
  L-R-R-R-R-R-R-RP-D
      RT-BR-RT

an easy way to make a compact restone signal that flashes if just but doing this

RE-RP>-RE
RE-<RP-RE

RE = redstone wire
RP> or <RP = repeater, arrow shows the direction

after you've made this you need to power it and quickly break and place one of the wires. the trick is to wait for on of the repeaters to shut off then place the wire. this causes it to flash from one half of the device to the other. you can do this with any amount of repeaters depending on the delay you want. i found this on a youtube video but i don't remember who it was by but this is the only design i have ever used so i hope this proved useful to anyone who wants a compact flashing signal

you need 3 of any blocks placed in a straight row with 3 redstone dust on top and 3 redstone torches on the back and cover those with blocks and it can empty a stack in no time

The fastest and most compact method that I can think of is to use two observers, two redstone dust, and two dispensers. This design takes six blocks of space, and activates a dispenser every two redstone ticks, according to my understanding of observers. Any solution that uses repeaters is likely to be slower; dispensers can face any direction. Given that dispensers will only activate every four redstone ticks we cannot fire arrows any faster without using multiple dispensers. Even the most compact designs will take a minimum of five or six blocks of spaces including redstone dust. This design is theoretically the fastest and most compact possible in the Java edition of Minecraft 1.17.