The transmission trio: dust, repeater, comparator

Three components make up redstone's transmission layer — the wiring that moves a signal from one place to another and reshapes its strength along the way. Redstone Dust carries the signal, a Repeater refreshes and delays it, and a Comparator measures it. Learn these three and you can route power anywhere.

Carrying the signal

Dust is the wire. It hauls strength across the grid, but every block costs it — so the real skill is knowing how far it can reach before it dies.

• Redstone Dust — carries a signal of strength 0–15, dropping 1 per block traversed, so a line starting at 15 fades to 0 after fifteen blocks.
• Redstone Dust — draws power only from *strong* sources (repeaters, comparators, torches, blocks a source has powered) or strongly powered solid blocks, never from weak power alone — the property that makes AND gates possible.
• Redstone Dust — can climb a ramp to dust one cell higher when the cell between them is opaque and the cell above the lower dust is clear; the reverse case lets it run back down.

Refreshing and delaying

Because dust fades, you need something to top the signal back up — and to control its timing. That is the repeater's job.

• Repeater — a one-way diode: it reads the cell behind it and outputs full strength 15 to the cell ahead, after a delay you can set from 1 to 4 redstone ticks.
• Repeater — is edge-triggered, so each rising or falling edge queues its own output transition independently; a pulse shorter than the delay still survives instead of being swallowed.
• Repeater — locks (input ignored, output frozen) when another powered repeater or powered comparator faces into its side.

Measuring the signal

The comparator is the one part that reads a signal's exact value rather than just on or off — and does arithmetic on it.

• Comparator — compares its rear input against the strongest of its two side inputs. In compare mode it passes the rear value through when rear ≥ side; in subtract mode it outputs rear − side, clamped to 0 or above.
• Comparator — outputs the measured value 0–15 as strong power to the cell it faces.
• Comparator — special-cases its rear input: it reads containers as fullness 0–15, a lit copper bulb as 15, and a lectern as its page level 0–15. Side inputs read only redstone carriers (e.g. dust, torches, repeaters, comparators), never the power level of a solid block.