Tutorials/Telegraph

A Minecraft telegraph works identically to a real telegraph device, sending a series of electric pulses over long distances to be decoded and interpreted by a receiving party. There are multiple designs, from the simple flashing redstone torch, to massive machines capable of reviewing, deleting, and editing messages before sending them to their destination. This tutorial will explain how to operate these devices, and how to create your own.

How They Work
All telegraphs, no matter how basic or complex they are, require four things: a sending device, an inverter, Redstone Wires, and a receiving device. The sender will just about always be in the form of a switch. Anything else, such as a button or pressure plate, can not be easily used to create a message, as they will remain activated for at least .9 seconds. A switch, on the other hand, can be shut off as soon as the player wants to, allowing for the quick pulses needed for telegraph languages such as Morse Code. After the sender comes the inverter, a simple logic gate that inverts its input to create the output. For instance, if the input wire is powered, the output wire will be off. These are almost always used in telegraphs because Redstone Torches (a common type of receiver) create their own power. This means that without an inverter, the torch will turn off when a pulse is sent. Although this is only an issue of appearance, it may lead to confusion during interpretation of the message, which is tricky enough by itself. Then comes the all-important wire, which allows you to send your message as far as you want (although the longer the wire, the more likely it is that something goes wrong). The wire consists of Redstone Wire, and, depending on its length, Redstone Repeaters placed on every fifteenth block. This will stretch out for as long as needed, until it reaches its destination; the receiver. Receivers can be anything from a Redstone Torch that blinks when a single pulse is received to a room filled with Redstone Repeaters, displaying the entire message before you.

Classic Telegraph
The most basic system, the classic telegraph is quite easy to build, but not so easy to use. It consists of one switch, one inverter, and one redstone torch for each direction of communication. This allows for a speedy construction and a space as small as 1x2x2 for each control room. In addition, due to its limited size and capability, it requires little to no knowledge of logic gates or circuitry, making it ideal for beginners or when you're low on redstone. The downside is that while you may be new to Minecraft, you have to be remarkably fluent in whatever language you decide to send the telegram in. This goes for the receiving party as well. In fact, they must begin reading the message the instant you begin sending it, or risk losing its meaning entirely. This quickly becomes problematic, especially when the server is lagging. So while the classic telegraph is compact and simple, it may be worthwhile to look into a more advanced system.

One-Way Telegraph
As indicated by the name, messages created in a one-way telegraph may only be sent in one direction, greatly limiting its capabilities. However, it is the only kind of telegraph with any real practicality in single player. If one were to have the sender in a mine, and the receiver in their house, they could effectively use it like a post-it stamp, leaving a message in their house to remind them, for example, that there was diamond in that mine. Expanding on this idea, they could have a series of redstone torches in their home indicating which of their mines had diamond or some other valuable element. Whenever another mine was discovered to have this elemnent, they could simply flip a switch, and the mine's corresponding torch would activate in the house. An example of this is shown on the right. Another use would be as a simple distress signal in multiplayer, as it is always an issue of having to simultaneously type your call for help and run away from whatever is troubling you.