GMRS Linking Overview
New England GMRS uses a repeater linking technology which was originally created by the Amateur Radio community called AllStarlink. AllStarLink.org used a open source PBX project called Asterisk. Unfortunately AllStarLink never got around to supporting the GMRS radio community, so a few individuals took the AllStarLink code and made a few changes, created private node registration servers and we now have GMRS linking technology. This is what makes open source software to great. Some of the organizations who runs private GMRS Node registration servers are, MyGMRS.com, GMRS.network, GMRSLive.com and ourself.. I am sure there are others but these are the most popular. All these organizations will issues you node numbers to join their linking network.
Node, node, node, what’s a node? Simply put a node is hardware that connects a radio to the internet. Unless a node is a hub. Sorry to confuse you. The name “Node” is also used to describe a function. So the piece of hardware, (node), can also be a server, hub or simplex node. The term server is kind of a technical term for what a node does. Since this is and overview, I am going to refer to server as a node.
Now we are getting somewhere. We have nodes and hubs. Nodes have a radio connected to it, Hubs do not. Nodes can connect to other nodes directly or they can connect to a hub. If a bunch of nodes connect to a hub, you have a network where what is said on one radio is heard on all the other radios. If a node connect to another node, you have a peer to peer connection where each peer hears the others traffic.
A simplex node where you just want to join and existing network is usually made up of a raspberry pi with a radio built on to it. Hotspotradios.com is a good source for a simplex node.
You can also connect a raspberry pi to and external radio, such as a Motorola CDM series. Some of these radios put out 45W and with an external base antenna, you could easily cover your neighborhood.
You can also use the raspberry pi for a hub, but a hub need more processing power the a node, so be sure you have enough to cover your intentions.
A node can also be used as a repeater controller. It will serve all the functions of linking like a regular node but it will also ID your system and key up your transmitter.
Now that you understand the basic concept of GMRS Linking, let’s get started.