Minecraft Pocket Edition - The ultimate redstone guide (Power sources)
Generation (Updated for 0.15)
Okay, now we know how to make redstone circuits using power sources, redstone dust, powered blocks, and devices. So let's break it down a little and look at the available power sources in Pocket Edition.Redstone torch
A redstone torch is a powered block, which means it gives power to all the blocks around it. However, it does not power the block beneath it. But it does transfer power to a block in the space above it.
In the example above, redstone lamp A is also acting as a powered block, and powering redstone lamp B.
Redstone torches have another, very useful ability. When connected to the side of a block, the redstone torch will turn off if the block is powered.
This is used to create inverse connections. An example being a daylight sensor that turns a light on, when the sun goes down.
How to craft:Lever
A lever is attached to a block - either on the side, on top, or underneath. When you flick it on, by tapping the lever, it continuously powers the 'block' containing the lever, and transfers power to the block the lever is attached to.
Flick the switch again to shut off power.
How to craft:Button
Buttons work similarly to levers. They are attached to a block, and provide power both to its own block and the block it is attached to.
However, the button only provides a momentary pulse of power which lasts for about one second. After that, the button turns itself off.
Buttons can be made of wood and stone. Wooden buttons stay on slightly longer than stone ones, and you can shoot wooden buttons with an arrow - meaning the button will stay on for as long as the arrow stays in the button.
How to craft:Pressure plate
A pressure plate powers its own block, and transfers power to the block beneath it, when it is stood on (by a player or a mob). Power remains on for as long as something is stood on the plate, but shuts off about a second after you leave it.
How to craft:Weighted pressure plate
A weighted pressure plate works like a normal plate. Stand on it to send power to adjacent devices, and turn the block underneath into a powered block.
But when you add in redstone dust, it's a different story. Now, power will only be sent a certain distance along the redstone trail, depending on how many items are sat on the plate.
How to craft:
The light version (gold) will send power along one block of glowstone dust for every four items sat on the plate (so you need 57 items to get all the way to the 15 block maximum of redstone dust).
The heavy version (iron) needs 42 items on the plate for each block of redstone dust.Daylight sensor
A daylight sensor becomes a power source when sunlight touches the block. Like the weighted pressure plate above, the daylight sensors signal varies based on how sunny it is.
Basically: electricity will flow furthest at noon, but not so far during the morning and evening. And not at all at night.
To get the most out of a daylight sensor, and have a lamp that turns on when it's dark out, we recommend using the inversion properties of the redstone torch, described above, to have a light that turns on when the daylight sensor is not powered.
How to craft:
That's Nether Quartz, so you'll need to enter The Nether to make this power source.Tripwire hook
Tripwire hooks and string are used to make tripwires. When a tripwire is set up, and something - a mob or a player - trips the wire, the hooks and any blocks they are attached to become powered.
When the character moves away from the wire, the power will turn off a second later.
How to craft:Trapped chest
Trapped chests are powered, and transfer power to the block the chest is sat on, when opened. Good for boobytrapping chests in your dungeon, and making trapdoors open or TNT detonate!
In version 0.14 you can make a double trapped chest, by putting two trapped chests next to each other.
How to craft:Detector rail
A detector rail is used as part of a minecart track, and provides power to itself and nearby blocks when a cart travels over the rail.'
In the example above, the light switches on when the cart travels over the rail. It turns back off after a couple seconds.
How to craft:Redstone Block
This is essentially a powered block. It provides power to any neighbouring devices or redstone dust, but it cannot transfer power to another block. You also cannot turn it on or off with buttons or levers.
How to craft:Observer
Observer is a a block that fires out a redstone signal whenever the block directly in front appears, disappears, or changes.
The observer has two sides: this silver pad is the input, and it looks at whatever block is placed in front of this pad.
The other side is the output. This is where the redstone spark appears. The redstone signal is incredibly short lived, but can be useful for setting off a piston or a dispenser or something.
And the observer can react to all sorts of things like a chest receiving an item, a sugar cane growing, a furnace finishing its cook, a cauldron filling up with water, a door opening, and more.
In this build, the note block plays a chime whenever the furnace finishes smelting a new object.
And in this build, the observers ads set off whenever the sugar cane grows three blocks high - at which point the piston pushes the cane off into the hopper and into the chest.
How to craft:
Next, let's take a look at the devices you'll be powering with all these power sources.