Basics: Redstone Wire

Redstone Wiring

When you place redstone dust on blocks it forms a wire, and connects itself to adjacent pieces directly north, east, south, or west of itself, but not diagonally.

The purpose of wire is simple, it carries a redstone signal just like electrical wire carries electrical current. There are limits though, The maximum amount redstone charge is 15 units, and you will lose 1 unit of "signal strength" per block of wire it moves through. That means that wire alone can only transmit a signal a maximum distance of 15 blocks from it's source. When wire carries a charge, it will glow at a brightness depending on the amount of signal in that piece of wire. I'll use a redstone torch, some wire, and some lamps to demonstrate how wire gradually diminishes signal strength.

Random Fact:
Signal loses strength as it moves through wire in the real-world too. This is called Attenuation.

A redstone torch is normally on, and outputs 15 redstone signal strength. It can also act as an inverter, but we'll talk more about that functionality in a later post.
A redstone lamp is a device that will glow when it receives a redstone signal.

I have placed a wire in a straight line and marked the signal strength of each block as the wire gets further away from the torch acting as our power source. Note that the torch does NOT charge the block it sits on, this would cause problems with the other functions of torches we will discuss later.

When the wire runs out of signal there is no more charge to carry as you can see in this pic below.

Wire can be placed on MOST solid block types, but some blocks will stubbornly refuse to allow wire on top of it.

Wire will also connect up or down 1 block. One way to transmit a signal up or down is to stair-step like this. I'll show you other ways later on.

When placing wire, keep in mind that if a wire will be blocked from moving up or down if there is a block which cuts the path as shown here:

However, if you need a block there AND you need wire to go down a block here, you can use a slab to allow the wire to connect downwards. Keep in mind that wire on top of the slab will also be charged, allowing you to split the signal vertically:

When I was first learning redstone, One of the things I found frustrating was that I didn't understand how to determine if a block would have a charge or not. It required the use of the same traditional process we use to learn most things:

The Learn-by-doing Process:
1. Trial
2. Error
3. Obscene Swearing
4. Repeat until you finally get it right

However, I've put together a couple examples in the hopes of minimizing this process for you.
Wire will transmit a charge to the block it sits on and the adjacent blocks. If a wire ends attached to a block that block will transmit a charge to the adjacent blocks as well. This means that a directly charged block will also the blocks on each side, top, and bottom, but not further than 1 block.

Even though a charge can move through a block to one next to it, wire alone will not pick up this signal. There are ways to do this which we'll see later.

I advise you to play around with wire and charges in creative mode on your own to get a good feel for how signal is transmitted. You'll need a firm grasp of these concepts before you can build more complex machines, and understand the posts I'll make in future days.

You can download and play this map and see these examples for yourself!
Click Here to Download Redstone Wiring Example Map

If you aren't sure how to play a downloaded map, I've written a tutorial for that too:
How to Play a Downloaded Minecraft Map