A DX Cluster is a packet node where DX chasers on any band or mode can post rare or interesting stations that they have worked or heard. Of course other people are doing the same thing too, so you can find new DX as well as telling others about the stations you have worked. Clusters tend to be linked to each other so that the amount of people using them is increased, thereby increasing the amount of posted DX. Other information can be found on clusters such as on-line call books, mail etc. You can talk to other stations connected to the cluster network too, in real time, whether at the node you are logged into or on another node connected to the network. You can also use converse mode, where several stations can talk to each other in the same way. Of course, the DX is still posted to you all the while!
PacketCluster nodes have been around since roughly 1985. The original PacketCluster idea came from Dick Newell, AK1A, and ran under DOS. In about 1992 Dick stopped the development of the PacketCluster software for amateur radio. Many systems are still using this relatively old DOS software today.
There are several new compatible cluster programs around now, including CLX. CLX is a clone of PacketCluster software that runs under the Linux operating system. Linux is fast becoming the choice for amateur radio stations because of it's flexibility, reliability and the lack of the memory limitations of DOS. Linux supports multitasking and is also multiuser. It has support for AX25, ROSE, NetROM and TCPIP built in, making it the ideal choice for amateur radio. It is also totally free!
CLX which stands for `CLuster software running under linuX' is written by Franta Bendl, DJ0ZY and Bernhard (Ben) Buettner, DL6RAI and has been under development since February 1994. To the user, its commands and features are mostly identical to a PacketCluster node. To PacketCluster nodes, CLX behaves exactly as they would expect, so can be integrated easily into a PacketCluster network.
This manual is designed to help you become familiar with the commands that CLX supports and to help you get the best from the program so you can enjoy working that rare DX! As CLX is being improved all the time, commands will be added as time goes by, so make sure you have the most upto date version of this manual. The version number of the manual will follow the CLX version number as closely as possible to help you check. If unsure, please ask your sysop.